DOCUMENT 316-98

RANGE SAFETY GROUP

TABLE OF CONTENTS

PAGE

CHAPTER 1 – GENERAL *

1.1 Scope *

1.2 Application *

1.3 Exclusions *

1.4 High Energy Systems *

1.5 Broad Beam Lasers *

1.6 Force-On-Force Exercises *

1.7 Content 1-3

CHAPTER 2 - APPLICABLE DOCUMENTS *

2.1 General *

2.2 Government Documents *

2.2.1 Standards *

2.2.2 Other Government Publications. *

2.3 Non-Goverment Publications *

2.4 Order of Precedence *

CHAPTER 3 - DEFINITIONS *

CHAPTER 4 - GENERAL RANGE CONTROL PHILOSOPHY *

4.1 General Policy *

4.2 Recommended Targets 4-3

4.3 Beam Control *

4.4 Specular Reflectors *

4.5 Hazards. *

4.6 Unprotected Personnel *

4.7 Warning Signs *

4.8 Personnel Protection *

4.9 Magnifying Optics *

4.10 Night Vision Goggles/Devices *

4.11 Specific Guidelines *

4.12 Laser Pre-firing and Post-firing Restrictions *

4.13 Stationary Continuously Operating Lasers *

4.14 Tactics *

4.14.1 Ground Laser Designators *

4.14.2 Airborne Wingman Laser *

PAGE

APPENDIXES

APPENDIX A - LASER SAFETY INFORMATION FOR FIRE CONTROL LASER

SYSTEMS A-1

1.0 Scope A-2

2.0 Fire Control Laser Safety Features A-2

2.1 Ruby LRFs.. A-2

2.2 Distance S. A-2

2.3 Current Laser Safety Summary.. A-2

2.4 Buffer Zones. A-12

2.5 Eye Protection. A-12

2.6 Fielded Laser System Descriptions. A-12

2.7 Inactive Lasers Descriptions and Associated Systems A-15

APPENDIX B - MULTIPLE INTEGRATED LASER ENGAGEMENT SYSTEM

(MILES) OPTICAL SAFETY SUMMARY B-1

1.0 Scope B-2

2.0 Applicable Documents B-2

3.0 Miles B-2

4.0 Schwartz Electro-Optic Controller Gun B-2

APPENDIX C - AIR TO GROUND ENGAGEMENT SYSTEM/AIR DEFENSE,

LASER AIR TO AIR GUNNERY SYSTEMS, PRECISION GUNNERY TRAINING

SYSTEM, AND AN/GTV-1 SAFETY SUMMARY C-1

1.0 Scope C-2

2.0 Applicable Documents C-2

3.0 Safety Summary C-2

APPENDIX D - SAMPLE CONTENT FOR LASER SAFETY SOP FOR

TRAINING WITH PORTABLE FIRE CONTROL LASERS D-1

1.0 Scope D-2

2.0 Warning D-2

APPENDIX E- EQUATIONS FOR LASER HAZARD EVALUATION E-1

1.0 Scope E-2

2.0 Applicable Documents E-2

3.0 Equation Applications E-2

3.1 Sloping Ranges.. E-2

3.2 Shipboard Laser System.. E-2

3.3 Hazard Evaluation.. E-3

3.3.1 Buffered Footprint Definition. E-3

3.3.2 Hazard Evaluation Without Specular Reflections. E-3

3.3.2.1 Single Laser Aircraft Heading. E-3

3.3.2.2 Multiple Laser Aircraft Headings E-3

3.3.2.3 Level Ground Examples. E-3

3.3.2.3.1 Example 1 (Level Ground). E-3

3.3.2.3.2 Example 2 (Level Ground). E-11

3.3.2.4 Unlevel Terrain. E-11

3.3.2.4.1 Target on Rising Terrain Or Hills Behind Target E-11

3.3.2.4.2 Falling Terrain in Target Area or Hills in Foreground E-11

3.3.2.4.2.1 Foreground Distances. E-11

3.3.2.4.2.1 Distance Beyond Target . E-11

3.3.3 Specular Reflections E-11

3.3.4 Aircrew E-14

3.3.5 Ground Personnel, Shipboard Personnel, Other Aircraft, and Surrounding

Community. E-14

3.3.6 Hazard Distances From Various Reflective Surfaces E-14

3.4 Footprint Determinations E-14

3.4.1 Ground Based Lasers. E-14

3.4.1.1 Vertical Buffer Far Boundary E-14

3.4.1.2 Vertical Buffer Near Boundary E-18

3.4.1.3 Horizontal Buffer E-18

3.4.2 Airborne Laser with Target on Level Ground E-19

3.4.2.1 Aircraft Minimum Altitude E-19

3.4.2.2 Left and Right Hand LSDZ E-22

3.4.2.3 Airborne Laser with Target on Sloping Ground E-22

3.4.2.3.1 Buffered Footprint E-22

3.4.2.3.2 For Far Target E-25

3.4.2.3.3 For Near Target E-25

3.4.2.3.4 Left and Right Hand LSDZ E-25

APPENDIX F - DOD LASER RANGE SURVEY CHECKLISTS F-1

1.0 Scope F-2

2.0 Checklists F-2

APPENDIX G - SPECULAR REFLECTION G-1

1.0 Scope G-2

2.0 Applicable Documents G-2

3.0 Specular Reflection Characteristics G-2

3.1 Flat Reflectors G-2

3.2 Hazardous Ranges of Reflected Laser Beam G-2

3.2.1 Reflection from Reflector Larger Than Cross Section of Incident

Laser Beam G-3

3.2.2 Reflection from Reflector Smaller than Incident Laser Beam Cross

Section G-8

APPENDIX H - SEPARATE TARGET (SEPTAR) AND SHIP’S TOWED TARGET OPERATIONS H-2

1.0 Scope H-2

2.0 Applicable Documents H-2

3.0 Septar Operations H-2

4.0 Ship's Towed Target Operations H-9

APPENDIX I - SATELLITE SAFETY PROCEDURES I-1

1.0 Scope I-2

2.0 References I-2

3.0 Definitions For Space-Directed Laser Emissions I-2

4.0 Applicability I-4

5.0 Concept Of Operations 1-4

6.0 JCCDOA Responsibilities I-5

7.0 Laser Facility Responsibilities I-6

FIGURES PAGE

4-1 Direct intrabeam viewing 4-2

4-2 Reflected intrabeam viewing 4-2

4-3 Example: warning sign 4-5

4-4 Sample safety exclusion cone for ground laser designator 4-12

4-5 Sample side view of safety exclusion volumes for ground laser

designator 4-14

6. Sample plan view of safety exclusion cones to prevent homing on laser

designator aircraft during continuous laser designation 4-14

continuous laser designator aircraft 4-15

4-8 Sample delayed laser designation safety exclusion cone, vertical view 4-16

and laser seeker field of view 4-17

air space 6-19

FIGURE 2D, ANSI Z136.1) 6-22

E-1 Laser footprint with single target - side view E-4

permitted for A-6E TRAM, OV-10D NOS, F111-Pave Tack, and

Pave Spike H-10

TABLES PAGE

6-1 Typical reflective surfaces 6-3

(COTS) military lasers A-8

for lasing from altitudes below 1 km MSL only) E-6

one nautical mile operation area - 0 to 360^o H-8

This document, Laser Range Safety, is published with the approval of the Range Commanders Council. The contents of this handbook are intended to serve as a guide to the safe use of lasers and laser systems used on military reservations and in military controlled areas. This edition of the 316 has been extensively revised from the previous issue.

Subject term (keyword) listing

Apertures Hazard Zone Laser Radiation Transmittance

Attenuation Lasers Optical Density Ultraviolet Radiation

Exclusion Zones Laser Radiation Radiant Energy Wavelength

This document is applicable to all Department of Defense (DOD) member ranges, operational test facilities where lasers are used, and all DOD laser operations conducted on non-DOD controlled ranges or test facilities. The guidance in this document does not replace other procedures or release individuals from compliance with the requirements of their particular service.

Certain provisions of this handbook are the subject of international standardization agreement, STANAG 3606, Evaluation and Control of Laser Hazards. When any amendment, revision, or cancellation of this handbook is proposed which is inconsistent with the international agreement concerned, the preparing activity will take appropriate action through international standardization channels, including departmental standardization offices, to change the agreement or make other appropriate accommodations.

A companion document, issued under the authority of DOD, is DOD Instruction 6055, Personnel Protection Policy Exposure to Laser Radiation. Its purpose is to provide uniform guidance for the safe use of military lasers and laser systems on DOD military reservations or military controlled areas worldwide. Copies of this document may be obtained through DOD publication channels. Other federal agencies and the public may obtain copies from:

Copies of Laser Range Safety may be obtained from the

The Range Commanders Council point of contact is

1.1 Scope

This handbook provides uniform evaluation guidance for the safe use of military lasers and laser systems on worldwide Range Commanders Council (RCC) military reservations or military controlled areas. Each military service has previously established normal procedures for approving laser ranges. This guidance is intended to supplement these procedures. It does not replace those procedures or release individuals from compliance with the requirements of their particular service. The authority for guidance is the Laser System Safety Working Group (LSSWG) established by DODI 5000.1 and Range Commanders Council. Guidance for lasers not addressed here should be obtained from the LSSWG through respective service health and safety organizations listed in Paragraph 1.2.

1.2 Application

This handbook applies to:

• All RCC ranges or operational test facilities where lasers are used and all RCC laser operations conducted on non-DOD controlled ranges or test facilities.
• Laser systems which have been evaluated by the DOD Laser Safety Review Board health and safety specialists for your respective service.

US Army Center for Health Promotion and Preventive Medicine

ATTN: MCHB-DC-OLO

Aberdeen Proving Ground, Maryland 21010-5422

DSN 584-3932/2331, Commercial (301) 671-3932

Space and Naval Warfare Systems Command (Code 00F)

2451 Crystal Drive

Arlington, Virginia 22245-5200

DSN 332-7235/73, Commercial (703) 602-7235

Armstrong Laboratory

Health Physics

Optical Radiation Division

Brooks AFB, Texas 78235-5501

DSN 240-4784, Commercial (210) 536-3625

• Outdoor laser use.
• Single-sided laser exercises.

• Fixed and rotary wing airborne laser platforms as well as ground- and ship-mounted laser systems.

1.3 Exclusions

This handbook does not apply to indoor use, for example, laboratory laser repair depots or industrial laser facilities because of the unique control measures required, industrial and construction lasers such as those used for surveying; and new technology laser applications.

1.4 High Energy Systems

High energy laser systems (lasers capable of cutting material or burning standard target material) require unique control measures. Use of these lasers must be approved by the local Laser Safety Officer (LSO) in coordination with the specialists designated in paragraph 1.2.

1.5 Broad Beam Lasers

Lasers with broad beam or autonomous scanning systems that are not directly under the operator's control may require additional evaluation assistance from the organizations listed in paragraph 1.2.

1.6 Force-On-Force Exercises

Force-on-force exercises using lasers and laser devices are special cases requiring additional controls. Exceptions are training lasers such as the Multiple Integrated Laser Engagement System (MILES) which is addressed in Appendix B. These force-on-force lasers must be addressed on an individual basis by the local LSO with assistance from the service component safety and health specialist designated in paragraph 1.2.

1.7 Content

This handbook contains appendixes, which give general and detailed policies to be followed in evaluating and recommending laser range safety procedures. Appendix A provides safety hazard control data for specific laser systems evaluated by each of the service safety specialists. Appendix B furnishes safety information on lasers used for scoring tactical exercises. Appendix C summarizes safety data for gunnery training systems and simulators. Appendix D is a sample of a laser safety standard operating procedure (SOP). Appendix E describes the equations used to determine Laser Surface Danger Zones (LSDZ)/Nominal Hazard Zones (NHZ). Appendix F contains checklists to be used for the laser safety pre-survey, the site survey, and the laser range safety evaluation reports. Appendix G discusses methods for evaluating hazards from specular reflections of the laser beam. Appendix H deals with safety policy for at-sea operations against ship towed targets and separate targets (SEPTAR). Appendix I addresses procedures for obtaining approval from the Space Command Control Center for Space Directed Emissions.

2. 2.1 General

The documents listed below are referenced in Chapters 3, 4, and 5 of this standard. This list does not include documents cited in other sections of this document or recommended for additional information or as examples. While every effort has been made to ensure the completeness of this list, document users are cautioned that they must meet all specified requirements of the documents cited in Chapters 3, 4, and 5, whether or not they are listed below.

3. 2.2 Government Documents

2.2.1 Standards. Unless otherwise specified, the following documents are those listed in the latest issue of the Department of Defense Index of Specifications and Standards (DODISS) and supplement cited in the solicitation and form a part of this handbook to the extent specified herein.

MILITARY STANDARDS

MIL-STD-1425A Safety Design Requirements For Military Lasers

And Associated Support Equipment

NATO STANDARDIZATION AGREEMENTS

STANAG 3606 Evaluation and Control of Laser Hazards

Unless otherwise indicated, copies of the above standards are available from the Standardization Document Order Desk, 700 Robbins Avenue, Building 4D, Philadelphia, Pennsylvania 19111-5094.

2.2.2 Other Government Publications. This standard supplements, but does not supersede the regulations for each Service. All offices responsible for laser safety will have a copy of the references applicable to their Service. The following government publications are referenced in this standard:

Joint Chiefs of Staff

JCS PUB 3-09.1 (JLASER) Joint Laser Designation Procedures

Department of Defense

DOD Instruction 6055.11 Protection of DOD Personnel from Exposure to

Radio frequency Radiation and Military Exempt

Lasers, 21 Feb 1995

DOD Directive 3200.22 Operation on National Ranges and Test Facilities

RCC Document Laser Range Safety, Range Safety Group,

316-91 DOD Range Commanders Council

US Army

TB MED 524 Control of Hazards to Health from Laser

Radiation

DAPM 385-63/MCO Policies and Procedures for Firing Ammunition for

P3570.1 Training, Target Practice and Combat

AR 40-46 Control of Health Hazards from Lasers and Other

High Intensity Light Sources

AR 385-30 Safety Color Code Markings and Signs

AMCR 385-29 Safety-Laser Safety

AR 40-5 Preventive Medicine

US Navy

SECNAV Instruction Exemption of Military Laser Products

5100.14B

SPAWAR Instruction Navy Laser Hazards Prevention Program

5100.12B

MCO 5104.1 Marine Corps Laser Hazards Control Program

NSWCDD/MP-94/289 Descriptions of Navy and Marine Corps Laser

Systems, by Sheldon Zimmerman, September 1995

BUMED Instruction Laser Radiation Health Hazards

6470.2A

EO410-BA-GYD-010 Technical Manual, Laser Safety

MCO P3570.1 Policies and Procedures for Firing Ammunition for

Training, Target Practice and Combat

 

 

 

US Air Force

AFOSH Standard 161-10 Health Hazards Control for Laser Radiation

USAFOEHL Report Base-Level Management of Laser Radiation

AL-TR-1991-0112 Protection Program

USAFOEHL Report Laser Range Evaluation Guide For

87-091RC0111GLA Bioenvironmental Engineers

AFI 13-212 Weapons Range Management

CODE OF FEDERAL REGULATIONS (CFR)

21 CFR Part 1040 Performance Standards For Light-Emitting Products

OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION (OSHA)

OSHA Publication 8-1.7 Guidelines for Laser Safety and Hazard Assessment

FEDERAL AVIATION ADMINISTRATION (FAA)

FAA 7930.2B Notices To Airmen (NOTAM)

Copies of specifications, standards, handbooks, drawings, publications, and other government documents required by contractors in connection with specific acquisition functions should be obtained from the contracting activity or as directed by the contracting officer.

4. 2.3 Non-Government Publications

The following document applies to the extent specified in this document. Unless otherwise specified, documents which are DOD adopted are those listed in the latest issue of the DODISS cited in the solicitation. Documents not listed in the DODISS are the issues of the documents cited in the solicitation.

AMERICAN NATIONAL STANDARDS INSTITUTE (ANSI)

ANSI Z136.1 Safe Use of Lasers

Copies of this document may be obtained through DOD publication channels for government activities. For all others, requests for copies should be addressed to American National Standards Institute (ANSI), 1430 Broadway, New York, New York.

 

 

5. 2.4 Order of Precedence

In the event of a conflict between the text of this standard and the references cited, the conflict will be referred to the military service specialists referenced in Chapter 1, Paragraph 1.2 of this document who have jurisdiction over the laser range. Nothing in this standard shall supersede applicable laws and regulations unless a specific exemption has been obtained.

The following definitions and terms are used in this handbook. For other definitions associated with laser safety, refer to ANSI Z136.1, Safe Use of Lasers.

Aircraft Exclusion Zone. A cone around the laser line-of-sight (LOS) that is 20 times the buffer angle. Laser operations must stop when another aircraft enters this zone.

Aperture. Any opening in the protective housing, shielding, or other enclosure of a laser product through which laser or collateral radiation is emitted, thereby, allowing human exposure to such radiation.

Attenuation. The decrease in the energy of any optical radiation beam as it passes through an absorbing or scattering medium or both.

Beam Divergence. The full angle width of the laser beam measured between the two points at which laser radiant exposure or irradiance in the laser beam is equal to 1/e (36.8 percent) of the maximum value.

Buffer Angle. The angle about the laser's LOS with apex at the laser aperture that is used to determine the buffer zone. As a minimum, it is typically set to five times the demonstrated pointing accuracy of the system plus the beam divergence. (Buffer angles for several lasers are assigned in Table A-1.)

Buffer Zone. A conical volume centered on the laser's LOS with its apex at the aperture of the laser, within which the beam will be contained with a high degree of certainty. The buffer zone is determined by the buffer angle.

Closed Installation. Any location where laser systems and products are used that will be closed or opaque to unprotected personnel during laser operations.

Collateral Radiation. Extraneous radiation such as secondary beams from optics, flash lamp light, radio frequency radiation, and x-rays that is not the intended laser beam as a result of the operation of the product or any of its components. System indicator lights would not normally be considered sources of collateral radiation.

Continuous Wave. The output of a laser that provides a steady or continuous output power rather than a pulsed output. A laser that emits a continuous output in excess of or equal to 0.25 seconds is a continuous wave laser.

Controlled Area. An area where the occupancy and activity of personnel within is subject to control and supervision for the purpose of protection from radiation hazards.

Diffuse Reflection. Reflection from a surface in which the beam is scattered in all directions, for example, a reflection from a rough surface. An ideal diffuse surface in which reflected brightness is independent of the viewing angle is called a Lambertian surface.

Electromagnetic Radiation. The propagation of energy consisting of alternating electric and magnetic fields which travel through space at the velocity of light and includes light, radio frequency radiation, and microwaves.

Exempted Lasers. Military lasers exempted from 21 CFR 1040, Performance Standards for Light-Emitting Products, where compliance would hinder mission fulfillment during actual combat or combat training operations or when the exemption is deemed necessary in the interest of national security. These lasers shall comply with MIL-STD-1425, Safety Design Requirements for Military Lasers and Associated Support Equipment. See DODI 6050.11.

Field of Detection. A volume of space within which a laser detecting system, for example, laser-guided munition, laser spot tracker, or night vision goggles (NVG), may acquire a laser designated target.

High Energy Laser. All class 4 lasers with power of at least 20 kilowatts for more than l.5 seconds or energy of at least 30 kilojoules for less than l.5 seconds.

Infrared Radiation (IR). Electromagnetic radiation with wavelengths within the range of 700 nanometers (nm) to 1000 micrometers (µm). This region is often divided into three spectral bands by wavelength: IR-A (700 nm to 1400 nm), IR-B (1400 nm to 3000 nm), and IR-C (3 nm to 1000 µm). IR-A is sometimes called near-infrared.

Irradiance (E). Measure of radiant power in watts per square centimeter.

Joule. A unit of energy, used principally for pulsed lasers, equal to l watt-second or 0.239 calories (cal).

Laser. Any device that can produce or amplify optical radiation primarily by the process of controlled stimulated emission. A laser may emit electromagnetic radiation from the ultraviolet portion of the spectrum through the infrared portion. An acronym for Light Amplification by Stimulated Emission of Radiation.

Laser Controlled Area. Any area that contains one or more lasers where the activity of personnel is subject to control and supervision for the protection from radiation hazards associated with laser operation.

Laser Footprint. The projection of the laser beam and buffer zone on the ground or target area. The laser footprint may be part of the laser surface danger zone if the laser footprint lies within the nominal ocular hazard distance (NOHD) of the laser.

Laser Radiation. Coherent electromagnetic radiation produced as a result of controlled stimulated emission within the spectral range of 200 nm to 1000 µm.

Laser Safety Officer (LSO)/Laser System Safety Officer (LSSO). At a particular installation, an individual trained in laser safety who is appointed by the commander to be responsible for control of laser hazards. The term Laser System Safety Officer is used by the Navy to differentiate the LSSO from the Landing Signal Officer (LSO). Each service's regulations will stipulate training requirements for LSOs/LSSOs and may, for example, differentiate among

• Laser Safety Consultants. Service experts who evaluate and advise on laser safety.

• Base Laser Safety Officer. Responsible for paperwork, administration, safety training, and compliance inspections at the installation, for example, Air Force Bio-Environmental Engineer (BEE), Army Radiation Protection Officer, or Navy Base Safety Office.

• Unit Laser Safety Officer. The individual in the laser user's chain of command who is responsible for all laser issues at the operational level, including but not limited to establishing unit specific laser regulations and procedures and ensuring compliance to the appropriate laser regulations and restrictions of the host facility, that the appropriate operational and safety training for the laser weapon shall be used, maintaining unit laser accountability, and ensuring that all other unit related laser safety issues are addressed.

• Range Laser Safety Officer. Responsible for the physical control of the Laser Range and for its use; including but not limited to establishing range specific Laser Safety Regulations and procedures and ensuring that all users comply with all appropriate laser safety regulations in place at the range. The Range Laser Safety Officer may be from the range installation or a visiting Unit Laser Safety Officer.

Laser Surface Danger Zone (LSDZ), Nominal Hazard Zone (NHZ). Designated region where laser radiation levels may exceed the maximum permissible exposure level.

Maintenance. Performance of adjustments or procedures to be performed by the user for ensuring the intended performance of the product. Maintenance does not include operation or servicing. This definition is equivalent to the DOD concepts of operator-performed maintenance and organizational maintenance. Organizational maintenance could include firing the laser.

Maximum Permissible Exposure (MPE). Laser radiation exposure levels published in ANSI Z136.1 and established for the protection of personnel. These are levels of laser radiation to which a person may be exposed without known hazardous effects or adverse biological changes of the eye or skin. The MPEs contained in ANSI Z136.1 are used in this handbook and are in concurrence with STANAG 3606.

Milliradian (mrad). Unit of angular measure. One mrad equals one thousandth of a radian. One degree equals 17.5 milliradians.

Micrometer (µm). A measure of length equal to 0.000001 meter (10^-6 meter). Formerly termed micron.

Nanometer (nm). A measure of length equal to .000000001 meter (10^-9 meter). Sometimes termed millimicron.

Night Vision Goggles/Devices. Any individual or crew served viewer which employs a nonthermal image intensification device (that is, ANVIS, cat's eyes, or AN/PVS-7).

Nominal Hazard Zone (NHZ). See Laser Surface Danger Zone.

Nominal Ocular Hazard Distance (NOHD). The distance along the axis of the laser beam beyond which the irradiance (W/cm²) or radiant exposure (J/cm²) is not expected to exceed the appropriate MPE, that is, the safe distance from the laser. The NOHD-O is the NOHD when viewing with optical aids.

Optical Density (OD). The following logarithmic expression for the attenuation produced by a filter such as an eye protection filter is

OD = log₁₀ (I_o/I_t)

where I_o is the power incident upon the filter and I_t is the power transmitted through the filter at a specific wavelength.

Optical Radiation. Electromagnetic radiation with wavelengths that lie within the range of 180 nm to 1 millimeter (mm). This radiation is often divided into three spectral regions by wavelength: ultraviolet radiation (180 nm to 400 nm), visible radiation (400 nm to 700 nm), and infrared radiation (700 nm to 1 mm).

Pulse Duration. The time increment measured between the half-peak-power points on the leading and the trailing edges of a pulse.

Pulsed Laser. A laser that delivers its energy in discontinuous bursts; that is, there are time gaps during which no energy is emitted. For the purpose of this handbook, a laser that emits a pulse for less than 0.25 second.

Radian (rad). A unit of angular measure equal to 57.3^o.

Radiance (L). The radiant energy per unit solid angle emitted by a source

Radiant Energy (Q). Energy in the form of electromagnetic waves, usually expressed in units of joules. Commonly used to describe the output of pulsed lasers.

Radiant Flux or Power (F). The time rate of flow of radiant energy given in units of watts. Used to describe the output power of continuous wave lasers or the average output power of repetitively pulsed lasers.

Radiant Exposure (H). The radiant energy per unit area incident upon a given surface. It is used to express exposure dose to pulsed laser radiation and is commonly expressed in joules per square centimeter or joules per square centimeter per pulse.

Reflectance or Reflectivity (P). The ratio of total reflected energy to total incident energy.

Repetitively Pulsed Laser. A pulsed laser with a sequentially recurring pulsed output.

Service. The performance of those procedures or adjustments described in the manufacturer's service instructions that may affect any aspect of the product's performance for which this handbook has applicable requirements. Service does not include maintenance or operation as defined in this section. This definition is equivalent to DOD concepts of maintenance above the organizational level.

Solid Angle (W). The ratio of the area on the surface of a sphere to the square of the radius of that sphere. Solid angle is expressed in steradians.

Specular Reflector. A mirror like reflector at the wavelength of the incident radiation.

Steradian (sr). The unit of measure for a solid angle. There are 4 pi steradians in a sphere.

Support Equipment. Devices or enclosures procured specifically for or modified for laser test, calibration, maintenance, or other support not part of the primary laser mission.

Transmittance or Transmissivity (t). The ratio of total transmitted radiant power to total incident radiant power.

Ultraviolet Radiation. Electromagnetic radiation with wavelengths between soft x-rays and visible radiation. This region is often divided into three spectral bands by wavelength: UV-A (315 to 400 nm), UV-B (280 to 315 nm), and UV-C (200 to 280 nm).

Visible Radiation (light). Electromagnetic radiation that can be detected by the human eye. Visible radiation is commonly used to describe wavelengths that lie in the range between 400 and 700 nm.

Watt (W). The unit of power or radiant flux equal to 1 joule per second. Used principally with continuous wave lasers.

Wavelength (l). The distance between two points in a periodic wave that have the same phase is termed one wavelength. The velocity of light in centimeters per second divided by frequency (given in Hz) equals the wavelength (given in cm).

2. 4.1 General Policy

Laser range safety is to prevent injury to personnel from laser radiation and misdirection of laser guided weapons. The objective of performing laser safety evaluations of DOD laser ranges is to provide guidance to protect personnel and property from misguided laser directed weapons and to ensure that no unprotected personnel are exposed to laser radiation above the protection standards specified in ANSI Z136.1. The goal is to accomplish this objection without placing unnecessary restrictions on laser system use. The safety evaluations shall be accomplished as described in the following subparagraphs.

1. Locate target areas where no line of sight exists between lasers and uncontrolled, potentially occupied areas within the NOHD for aided and unaided viewing.

4.1.2 Remove specular surfaces from targets and target areas. Do not use a laser to designate or range still water, flat glass, mirrors, glazed ice, plexiglass, or other specular reflectors.

4.1.3 Laser beams and the associated buffer zone must be terminated or the radiation level attenuated below the MPE limit within the controlled range or test facility or in controlled airspace. If energy below the MPE is allowed to leave the range, the possibility of optically aided viewing by unprotected individuals must be considered in the safety evaluation.

4.1.4 Lasers should be of the lowest emission level consistent with mission requirements.

4.1.5 On most ranges, some personnel and moving targets are required to be on the range during laser operations for instrumentation operations, munitions impact spotting, and other required activities. The locations of all occupied areas must be determined and evaluated relative to the laser hazard area. The type of laser protective devices required, if any, must then be determined for each occupied location.

4.1.6 Safety evaluations and degree of restrictions shall consider extent of range boundaries, required warning signs, number and location of specular reflectors, ease of public access to the range, airspace restrictions, local operating procedures, and environmental conditions (see Figures 4-1 and 4-2).

Figure 4-1. Direct intrabeam viewing

4.1.7 In joint laser exercises, all parties shall be informed of the intended laser operations prior to scheduling including the Range Control Office, Range Safety Office, LSO/LSSO/Radiation Protection Office (RPO), and Liaison Office for the services involved.

When coordinating with these offices, ensure that NOTAM and Notice to Mariners (NOTMAR) are prepared and issued in accordance with FAA, United States Coast Guard (USCG), and National Imagery and Mapping Agency (NIMA) regulations as required. Ensure that use of class 3 or class 4 lasers above the horizon is approved by U.S. Space Command (Laser Clearing Housing) DSN 268-4496, or commercial (719) 474-4496.

2. 4.2 Recommended Targets

Recommended target areas are those without specular (mirror like) surfaces. Glossy foliage, raindrops, fog, snow, and most other natural objects are not considered to be specular surfaces that would create ocular hazards. All reflectors posing a specular reflectance hazard shall be removed from the Laser Surface Danger Zone (LSDZ). Calm, smooth water and clean ice can reflect laser beams, especially at low angles of incidence. Consider these potential reflections when establishing target areas. If these potential reflections have not been considered for the approved target area, ranges shall be closed when water begins ponding on the ground.

4.3 Beam Control

When target areas have no flat specular surfaces, range control measures can be limited to the control of the beam path between laser and backstop.

3. 4.4 Specular Reflectors

Specular surfaces within distances (see Appendix A, Tables A-1 and A-2) of the laser target, visible to unprotected personnel through binoculars or magnifying optics, will be removed, covered, painted, or destroyed. For lasers used from fixed wing aircraft, the entire buffered laser footprint area shall be cleared of specular reflectors (see Appendix E).

4. 4.5 Hazards

4.5.1 Laser devices such as those listed in Appendix A, Table A-1 and A-2, can seriously injure the unprotected eyes of individuals within the hazard zone of the laser beam. Intrabeam viewing of either the direct beam or a beam reflected from a flat mirror like surface may expose unprotected eyes to a potential injury and must be avoided.

4.5.2 Every diffuse reflecting object that the laser beam strikes will reflect back some energy in all directions and toward the laser. This diffusely reflected energy will not be hazardous if the laser is located greater than a distance "t" from the target (see Tables A-1 and A-2). To avoid hazardous specular reflections, the area around the target must be cleared of specular (mirror like) reflectors. The hazard of exposure to the skin is small compared to the eye; however, personnel should avoid direct laser beam exposure to the skin within distance "t" from the laser.

4.5.3 A less severe hazard exists for the devices listed in the tables of Appendixes C and D, but intrabeam viewing of the laser beam at distances less than that specified with the unprotected eye should be avoided.

4.5.4 Dazzle and momentary flash blindness can occur from visible laser exposures below MPEs. Laser eye protection may not attenuate the radiation sufficiently to eliminate these effects. Appropriate precautions must be taken if personnel performing critical tasks, such as flying aircraft, may be exposed to laser radiation levels that may cause dazzle or momentary flash blindness.

5. 4.6 Unprotected Personnel

Unprotected personnel must not be exposed to laser radiation in excess of the MPE from either the direct or reflected beam.

6. 4.7 Warning Signs

Evaluation of each anticipated operating condition must include development of procedures for ensuring proper placement of warning signs. Local SOPs should provide for the placement of temporary signs during operation. Signs should be in accordance with AR 385-30, SPAWARINST 5100.12B, or AFOSH Std 161-10 (see Figure 4-3).



Form # NAVSEA 1995/17 Stock No. 0118-LF-020-1100

Available from:

Naval Publications and Forms Center

Code 1062

5801 Tabor Avenue

Philadelphia, PA 19120-5099

Order on DD FORM 1348. Provide cost accounting data. Cost $118/package of 5.

Customer Service phone DSN 442-2626.

 

 

Figure 4-3. Example: warning sign.

 

8. 4.8 Personnel Protection

Individuals within the horizontal or vertical LSDZ such as moving target operators, support personnel, and aircrew members should wear laser protective eyewear with curved protective lenses during laser firing. The curved lenses are necessary if there is a probability that laser eye protection will specularly reflect the beam into an uncontrolled area. Eye protection with side shields may be required if the laser beam can get behind the lens. Eyewear must be approved for the wavelength of the laser device being fired. A laser filter designed to protect against one wavelength of laser may not protect against harm from another. Appendix A, Table A-3 provides the wavelength and optical density required for the current fielded devices. If more than one type of device is used, protective measures must cover all devices. For devices of the same wavelength, the highest required optical density will be used.

9. 4.9 Magnifying Optics

The use of magnifying daylight optical devices to observe the target during laser operation is permitted if flat mirror like surfaces have been removed from the target area. Mirror like targets can be observed only if appropriate laser safety filters are placed in the optical train of the magnifying optics. Protected optics such as sights must be so marked.

10. 4.10 Night Vision Goggles (NVG)/Devices

Because NVGs provide a substitute for the human eye during night time operations, NVGs must be considered a mission critical item. Devices such as ANVIS or cats eye, MXU-810/U, are designed for aviators and are as important as the aviator’s eyes during night time operations. Although some NVGs will protect the human eye from laser damage (NOTE: Cats eye NVG will not protect the human eye.) The damage threshold for NVGs may be as low or lower than the damage threshold for the human eye. The impact of damaging the aviator’s NVGs during flight could be fatal. Therefore these devices must be physically (optical or electrical) or procedurally protected from laser damage. Many resources exist to determine the safe operating ranges for NVGs and several service-specific points of contact are listed below:

Naval Research Laboratory

Code 6656

4555 Overlook Avenue

Washington, DC 20375-5345

(202) 767-6978

USA CECOM NVESD, AMSEL-RD-NV-LPD

10221 Burbeck Road, Suite 430

Fort Belvoir, VA 22060-5806

(703) 704-2031

Wright Laboratory/MLPJ Building 651

3005 P Street, Suite 1

Wright Patterson AFB, Ohio 45433-7702

(513) 255-3808, ext-3169

11. 4.11 Specific Guidelines

These specific guidelines are provided as a minimum to ensure proper control of hazardous laser energy:

4.11.1 Publish and enforce safety regulations for laser usage in specific areas. Provide detailed written procedures to minimize laser radiation hazards and other laser related range hazards such as erroneously homing on the laser target designator and wrong targets.

4.11.2 Assign a laser safety officer (LSO) at the base, range, and user levels as defined in chapter 3 to be responsible for ensuring appropriate safety control measures are followed.

4.11.3 Require users to prepare a safety SOP for each different laser system and different type of laser operation. At any enclosed area such as a preliminary laser testing facility, post a generic safety SOP.

4.11.4 Keep records of the date, start and stop time for lasing periods, and type of laser or other appropriate information for each laser operation.

4.11.5 Post the range boundaries to advise the public of the presence of laser operations, where deemed appropriate by the local laser safety officer. These signs shall be in accordance with MIL-STD-1425 (see Figure 4-3).

4.11.6 Fire lasers only at authorized targets.

4.11.7 Where possible, use eye-safe attenuating filters over the laser output.

4.11.8 Do not fire the laser at still water, flat glass, mirrors, glazed ice, Plexiglas, or any other specular reflectors, unless specifically authorized by the Laser Safety Officer.

4.11.9 Do not fire the laser at aircraft, unless specifically authorized by the Laser Safety Officer.

4.11.10 Before operating fire control lasers or rangefinders, be certain that the target is positively identified under the crosshairs of the scope, or on the operator's monitor, or in accordance with specific safety procedures approved by the Laser Safety Officer.

4.11.11 Cease laser operations if the operator or range control is dissatisfied with target tracking.

4.11.12 Cease laser operations if unprotected or unauthorized personnel enter the laser hazard area.

4.11.13 Clear the range using range personnel or by a flyover of the range to ensure that no unprotected or unauthorized personnel are in the laser hazard area, including all boats where island or shoreline ranges are involved.

4.11.14 For air operations, cease laser firing if unprotected or unauthorized aircraft enter the operations area or a restricted zone between the aircraft carrying the laser and the target. The restricted zone for most fire control lasers is defined as 20 times the assigned buffer zone. For example, when using a laser with an assigned buffer zone of 5 milliradians, the restricted zone around the laser beam out to the NOHD for other aircraft with unprotected personnel would be a 100 milliradian or 5^o (half angle) cone surrounding the laser LOS to the target with the aircraft carrying the laser at the apex.

4.11.15 Maintain two-way communication between the laser system operators and all affected range personnel.

4.11.16 Establish a laser operator training program.

4.11.17 Provide a pre-mission brief to all laser operators and affected personnel prior to laser operations. The brief shall include all potential hazards such as radiation and weapons misguidance, control measures specific to the lasers employed, and the range upon which they are used. As a minimum, the brief shall include

4.11.17.1 maps depicting the targets, target areas, and their laser hazard area;

4.11.17.2 drawings or photographs of the target/targets to be used;

4.11.17.3 run-in headings and flight profiles to be used for airborne laser operations and permissible firing fans for ground based laser operations; and

4.11.17.4 review of mission profiles to prevent misguidance of laser guided weapons (LGW) by ensuring that the LGW or laser spot tracker field of view (FOV) always encompasses the target and does not encompass the space near the laser designator.

4.11.18 Do not direct class 3 and 4 lasers above the horizon unless coordinated with the US Space Command (Laser Clearing House) and with the regional FAA office for laser radiation above the MPE outside restricted airspace (see Appendix I).

4.11.19 Ensure ground based lasers are at the approved operating position or firing points and always pointed down range toward the target.

4.11.20 For ground based lasers, ensure all unprotected personnel in the immediate area of the laser firing position are outside the laser surface danger zone or behind the laser operator while the laser is in use. Laser eye protection is not required for laser operators or observation personnel viewing a target area from which specular reflectors have been cleared, even when binoculars are used. However, personnel must never enter the LSDZ without appropriate eye protection.

4.11.21 Medical surveillance, especially of down range target area personnel, shall be in accordance with each service's medical regulations. Immediately report any suspected injury or defective equipment (for example, misalignment of the laser beam with the pointing optics) to the cognizant supervisor, so appropriate action can be taken to remove the product from service until it has been cleared for operation by competent authority. Include laser injuries in the local medical emergency plans. Timeliness in examination and treatment of suspected laser injuries by specialists to prevent further internal damage is of the utmost importance. The following commands retain opthamologists trained in treating laser injuries:

USAMRD-BAFB

7914 A Drive

Brooks Air Force Base, Texas 78235-5138

Commercial: (210) 536-4622

DSN: 240-4622

Fax: (210) 536-3450

AL/OEO

8111 18th Street

Brooks Air Force Base, Texas 78238-5215

Commercial: (210) 536-4816

DSN: 240-4816

Fax: (210) 536-3903

AL/AOCO

2507 Kennedy Circle

Brooks Air Force Base, Texas 78235-5117

Commercial: (210) 536-3241

DSN: 240-3241

Fax: (210) 536-5165

Brooks Air Force Base Command Post is manned at all times: DSN 240-3278, Commercial (210) 536-3278

 

4.11.22 Do not operate the laser or use it experimentally outside the range area without the operation being specifically authorized by the local LSO. Follow the safety procedures of ANSI Z136.1 for laser operations within any indoor firing pretest or laser testing facility. For example, use electrical door interlocks to prevent laser firing if entry door is opened.

4.12 Laser Pre-firing and Post-Firing Restrictions

When lasers are not in use, hazardous laser output shall be prevented by use of such devices as output covers or rotating the laser into the stow position, unless otherwise specifically authorized by the local LSO. The following subparagraphs should be included in pre and post-firing checklists.

4.12.1 Any maintenance performed in a range environment must be in accordance with operating procedures approved by the local LSO.

4.12.2 Pre-fire checks that require operation of the laser may be made in a controlled area with the laser beam terminated by an opaque backstop. Pre-fire checks that do not require operation of the laser, but require use of the optics, may be safely made in a controlled area. To operate the optics without firing the laser, institute operating procedures to ensure power to the laser is turned off in accordance with local lock-out/tag-out procedures.

4.12.3 The laser exit port must be covered or laser otherwise stowed and turned off when transiting the range or traveling on public highways or in uncontrolled air space or shipping lanes.

4.12.4 Non-laser operations such as viewing through common optics can be conducted in a non-laser controlled area with the laser exit port cover removed. This non-laser operation can be accomplished by instituting procedures that ensure power to the laser is turned off.

12. 4.13 Stationary Continuously Operating Lasers

Uses of lasers such as the light detection and ranging (LIDARs) or space probes operating continuously in airspace may require additional controls. Besides coordinating these emissions with the FAA and Space Command, automatic shut down features may be necessary to prevent illumination of aircraft above MPE or to prevent glare danger. These shut down features could be a radar beam which senses incoming craft or an aircraft transponder which signals the laser to shut down (see Appendix I).

14. 4.14 Tactics

Laser guided munitions and other laser detectors have unintentionally acquired radiation sources within the field of detection other than the target resulting in fratricide. Fields of detection vary and are specific to individual weapons. All tactics must be planned to ensure that the angle between the laser designator LOS and laser detectors (for example, laser guided munition, laser spot tracker, and NVG) will not mistakenly aim the munition at the laser source or scattered radiation from the laser platform, see Joint Chiefs of Staff publication 3-09.1 (JLASER).

4.14.1 Ground Laser Designators. When employing laser spot trackers with ground laser target designators, the following procedures will be used

4.14.1.1 Terminal controllers will provide aircrews with an attack heading or laser-to-target line. The attack heading must allow aircrews to acquire the laser energy reflected from the target. Ensure designators for other targets on the range are not using the same laser codes.

4.14.1.2 Because of the possibility of false target indications caused by atmospheric scatter from the laser beam within short distances from the laser exit port, attack headings should avoid target-to-laser designator safety cones unless the tactical situation can safely dictate otherwise. (The safety cone is usually defined as a 20^o cone whose apex is at the target and extends 10^o degrees either side of the target-to-laser designator line.) The scattered radiation that the seeker can detect may be caused by both Rayleigh and Mie scattering. Rayleigh scattering of radiation from atmospheric molecules is what makes the sky blue. It is strongest for shorter wavelengths (varies inversely by the fourth power of the wavelength) and is about twice as strong at 0^o and 180^o than at 90^o from the laser LOS. However, at 90 degrees, it shows the greatest polarization. Mie scattering from aerosols is very strong in the forward direction of the beam even in the cleanest of atmospheres. It is not as dependent on wavelength as Rayleigh scattering and has no strong polarizing effect.

4.14.1.3 The optimal attack zone is a 50^o zone from 10^o to 60^o either side of the target-to-laser designator line and at an elevation that will ensure adequate target acquisition. The risk of acquiring the laser designator instead of the target in this zone varies from moderate to low as the angle increases.

4.14.1.4 WARNING. The degree of hazard to ground personnel operating the laser target designator varies with the attack angle of Laser Spot Tracker from the laser LOS. See Figure 4-4. In some situations, laser spot trackers have shifted from the designated target to the laser target designator while operating in the 50^o attack zone. For this reason, laser spot trackers should not be used as the sole source for target verification. Aircrews should verify they are attacking the target through additional means such as visual description or non-laser target mark. At a minimum, the laser spot cue provided in the cockpit must be evaluated and compared to the expected target location. For close air support missions, the target location given in line 6 of the 9-line brief should be used to confirm the laser spot. For aircraft equipped with an Inertial Navigation System (INS) or Global Positioning System (GPS), steering cues provided by these aids should always be used to back-up the laser mark. Additional aids include, but are not limited to, visual target description, laser pointers, or non-laser target marks provided by direct or indirect fire from conventional weapons. If the laser spot tracker cue is not coincident with the expected target location, aircrew should not deliver ordnance on the laser spot.

To reduce the potential for seeker lock-on to the designator position, the designator should be masked from the seeker field of view. Terrain, vegetation, or other obstruction can sometimes mask the designator.

WARNING: DOES NOT GUARANTEE THAT THE LASER

SEEKER WILL NOT LOCK ONTO THE LASER DESIGNATOR.

When the seeker's acquisition can be monitored by watching the aircraft with the laser spot tracker or seeing a laser guided bomb (LGB), it may be possible to detect an improper lock-on in time to prevent a mishap by aborting the bombing run. See Figures 4-4 and 4-5 for an example of a plan for ground laser designator tactics. Refer to individual Laser Spot Tracker/Laser Guided Weapons technical orders and procedures for additional safety information.



 

NOTE : Situational check must ensure seeker field of view covers the target and not the area of the laser target designator out to a distance in front of the designator where scatter cannot be detected by the seeker. Because this is an example, details should be obtained from system specific documents and publications such as JCS PUB 3-09.1.

4.14.2 Airborne Wingman Laser Designation. Laser guided weapons (LGW) or laser spot trackers (LST) can erroneously lock onto the scattered radiation from buddy lase or wingman aircraft laser designators. In addition, if the airborne laser designator is pointing towards the LGW or LST, the designator itself may be tracked. In lock-on-before-launch (LOBL) mode, the LGW seeker LOS can be displayed in most launch aircraft. If the LOS cue is well above the horizon, then the missile is probably locked onto an erroneous spot such as the designator aircraft or atmospheric scatter instead of the desired target spot, and the mission should be aborted. If the LGW is employed in the lock-on-after-launch (LOAL) mode, no LGW LOS cueing is provided to the launch aircrew. Wingman designators must be aware that even if a LOBL is planned, launch aircrews train to employ the missile in a LOAL mode if a laser spot is not received once clearance to launch has been given.

4.14.2.1 If the missile properly locks onto the target in an LOBL mode, the only risk to the designator would be a midair potential if the designator aircraft is operating below the missile trajectory apex. In an LOBL mode, the wingman aircraft altitude should remain substantially above the nominal LGW apex altitude, keeping in mind that missiles can climb to altitudes well in excess of their nominal apex values especially if they are tracking a laser designator.

4.14.2.2 When employed in an LOAL mode, the laser guided missile will execute a climbing profile searching for a laser coded energy prior to tipping over and scanning its FOV along the ground. The risk to the wingman designator is highest during the initial staring phase of the LGW profile. If it locks onto the designating aircraft, there is a high probability that it will track and kill the laser designator. The dimensions of the instantaneous FOVs of the LGWs are not absolute, and some are capable of detecting forward or back scattered radiation at many degrees off boresight.

4.14.2.3 The geometry and timing for buddy/wingman lase tactics must be precise to preclude the weapon from targeting the designating platform. Designator profiles behind the launch platform are inherently the safest. If that is not possible, a designator profile must be selected that will keep the aircraft out of the LGW FOV. Figures 4-6, 4-7, 4-8 and 4-9 show examples of laser designator NO FLY CONE profiles. Refer to individual LST/LSW technical orders and procedures for additional safety information. Ensure other designators on the range are not using the same laser code.





 

 

 



Figure 4-7. Sample vertical view of safety exclusion cones to prevent homing on

continuous laser designator aircraft.

 

 



 

 



 

 

 

 

 

 

NOTE: To minimize risk of fratricide, ensure the target is always in the seeker FOV when the laser designator is on and minimize intersection of the laser seeker FOV with the laser beam especially close to the laser.

CHAPTER 5

RANGE EVALUATION PLANNING REQUIREMENTS

 

15. 5.1 Background

Prior to any laser range operations, the hazards of using the system on the range must be fully evaluated. Both the laser user and the range control personnel must mutually agree on the conditions for laser operations. A sample checklist is provided in Appendix F for this data collection.

16. 5.2 Laser User

The laser user shall provide

 

5.2.1 technical orders, technical manuals, and reports on the laser system and associated hazards as requested by the range evaluator;

5.2.2 the NOHDs and sources of evaluations or the parameters required to perform the safety evaluations;

5.2.3 standard operating procedures on the laser;

5.2.4 intended operational environment for laser use including types of targets and position, laser firing locations, run-in headings, maximum and minimum firing altitudes and ranges, direction of laser operations, and any other special considerations;

5.2.5 laser systems parameters; and

5.2.6 hazardous failure modes, that is, those that affect laser parameters or beam steering, secondary beams, inadvertent firing, and other potential system problems.

17. 5.3 Range Operator

The range operator shall provide

5.3.1 local instructions that outline general range operating and safety requirements and

5.3.2 detailed range maps showing laser location, target location, restricted airspace or artificial backstops, flight path, range boundaries, populated areas, public roads, and no lase areas.

18. 5.4 Range Evaluator

The range evaluator will review laser system data, maps, targets, instructions, SOPs, and other information provided by the laser user and range operator to determine which existing requirements impact the safety of laser operations on the range such as

5.4.1 limitations on allowable laser locations and run-in headings for aircraft,

5.4.2 minimum and maximum flight altitudes (airborne platforms only),

5.4.3 airspace surveillance,

5.4.4 flyover requirements to ensure range security,

5.4.5 locations of control towers and other manned areas

5.4.6 locations of non-controlled personnel access to the areas surrounding the target area, and

5.4.7 specific information on maintenance, boresighting, or other activities on the range.

CHAPTER 6

RANGE EVALUATION REQUIREMENTS

 

19. 6.1 Evaluation Sequence

A laser range evaluation can be performed for a specific laser system or for a group of similar lasers. An evaluation of a group of similar lasers is recommended if available land permits and the mission is not severely impacted. To perform this general evaluation, the worst case conditions of all possible systems and missions are used. If these conditions are too restrictive, separate evaluations for each system must be performed. The evaluation should be conducted on site at the laser range including a flyover, drive-through, and walk-through inspection. To simplify the range evaluation procedure, it may be divided into five steps: laser; range; target; mission; and laser surface danger zone.

6.1.1 Laser. To evaluate a laser for use on a range, it is necessary to determine the hazard potential of the system by determining the following items.

6.1.1.1 Maximum Permissible Exposure (MPE) Limits. Determine the applicable MPE for the laser being evaluated. The MPEs are provided in ANSI Z136.1.

6.1.1.2 Laser Classification. Classify the laser using the procedures in MIL-STD-1425 to determine what laser control procedures are required such as interlocks and warning labels.

6.1.1.3 Nominal Ocular Hazard Distance. Determine the distance from an operating laser to the point where the laser is no longer an eye hazard by using the procedures designated by the specialists listed in subparagraph 1.2.2 or use the values given in appendixes A and C.

6.1.1.4 Reflections. Determine if the laser is capable of producing hazardous reflections under established conditions using procedures designated by specialists listed in subparagraph 1.2.2 or appendixes A and C.

6.1.1.4.1 Specular Reflections. Determine what kinds of surfaces will act as specular reflectors at the laser wavelength (see Figure 6-1, Table 6-1, and Appendix G).

6.1.1.4.2 Diffuse Reflections. Determine if the laser is capable of producing hazardous diffuse reflections. Lasers that can produce hazardous diffuse reflections are classified as class 4 and have an associated diffuse reflection hazard distance (t). It is unusual for field type lasers to produce diffuse hazards. Presently, only the M60 tank, the M551A1 Sheridan Vehicle, and the OV-10D Night Observation System produce hazardous diffuse reflections. Normally for a diffuse hazard, the beam path out to the distance,t, as provided in Table A-1, is a denied occupancy area and no objects are permitted in the beam path out to this distance.



TABLE 6-1. Typical Reflective Surfaces

6.1.1.5 Optical Density. The degree of protection required to reduce the incident laser energy to safe eye and skin levels must be determined. These levels are available in appendixes A and B and from the designated specialists listed in subparagraph 1.2.2.

6.1.1.6 Optical Viewing. Consider the possibility of personnel directly viewing the beam (intrabeam viewing) or reflections of the beam through optical instruments such as binoculars. The light gathering ability of the optics can significantly increase the degree of hazard for the eyes (increase OD and NOHD). Procedures to evaluate this hazard are in AFOSH Standard 161-10, ANSI Z136.1, and TB MED 524. Some evaluation results are included in appendixes A and B.

6.1.1.7 Atmospheric Attenuation. Atmospheric attenuation can be quite high for infrared lasers operating over distances of 10 kilometers or greater. It can reduce the NOHD considerably and should, therefore, be included in the laser evaluation.

6.1.1.8 Laser Platform Stability. The stability of the laser platform must be evaluated to determine the pointing accuracy of the laser system. The pointing accuracy will determine the size of the buffer angle. The typical buffer angle for airborne (aircraft), ground based, or shipboard stable platforms (tripods) is 5 milliradians, while hand-held lasers normally require 10 milliradians. Paragraph 6.8.1 further discuss the buffer angle.

6.1.2 Range. A range map, a topographic map, and an air space map of the area are needed for the laser range evaluation.

 

6.1.2.1 Range Map. The range map is essential to establish accurate distances from target area to range boundaries. The range map should show the boundaries and include geographic items such as towers and buildings. Boundaries of special purpose areas such as an airstrip and the location of the targets are required.

6.1.2.2 Topographic Map. The topographic map is important because it enables the evaluator to determine the elevation of the target area relative to the surrounding terrain. It is important that no portion of the beam, which exceeds the MPE limits, extends beyond the controlled area. Using natural geographic backstops such as hills can control the beam. A topographic map is very helpful in identifying these backstops and in repositioning targets if necessary.

6.1.2.3 Airspace Map. Controlled airspace is that airspace associated with the range having specific, possibly non-coincident lateral boundaries and a specific minimum and maximum altitude. It is important that this controlled airspace and any other special conditions are made known. Laser operations are not normally authorized outside the controlled airspace or when other aircraft are between the laser and the target. In addition, if the beam is directed up, or if hazardous reflections could exceed the height of the controlled airspace, additional controls may be necessary.

6.1.3 Target and Target Area. The size, location, and type of targets to be fired at on a range are of primary importance in determining the hazard zone.

6.1.3.1 Optimum Target. The optimum target from a safety point of view is a non-reflective surface. Flat specular surfaces must be removed or covered, because reflections from these surfaces can retain high collimation. A flat specular surface is one in which a relatively undistorted image can be seen. Examples of specular surfaces are windows, Army tank vision blocks, searchlight cover glass, plastic sheets, glossy painted surfaces, still water, clean ice, flat chrome, and mirrors. Snow is not a specular surface, but if thawed and refrozen, hazardous reflections can be found especially at low angles of incidence. Glossy foliage, raindrops, and other natural objects are not hazardous targets since their curved reflective surfaces as well as other curved reflective surfaces cause the beam to spread and the reflected irradiance (energy per unit area) decreases quickly with distance. The only exception is concave reflective surfaces, which can focus the reflected beam and cause the reflection to be more hazardous than the incident beam. Practically, these reflections are of little concern because it is improbable that the surface is perfectly concave (focuses the beam to a single point) or perfectly reflective. Additionally, the focal points of concave reflectors would probably be very close to the object (small radius of curvature) and be of little concern, because people do not normally put their head close to objects and if they did, they would probably block the incident beam. Concave surfaces with a large radius of curvature which could focus at longer distances would appear nearly flat and must be removed or covered. Although curved surface reflection may not be hazardous at typical laser-to-target engagement ranges, large shiny curved surfaces should be removed. An example of such a surface is a curved automobile bumper. Lastly, a diffuse surface is one that totally distorts (or diffuses) the beam shape, normally resulting in a safe-to-view reflection from outside the target area. Table 6-1 lists some common items found in a typical range area and their type classification for reflection. Appendix G provides additional information.

6.1.3.2 Size and Location. The number and location of targets (distribution) will affect the size of the hazard zone. On ranges with limited space, it is important that all targets be as close together as tactically feasible.

6.1.3.3 Separate Target. See Appendix H for Navy separate target (SEPTAR) operations.

6.1.4 Mission. An evaluation must be made for each type of laser used on the range. The laser operating mode, that is, air-to-ground, ground-to-ground, ship-to-target must be determined. At the present time, air-to-ground, ground-to-ground, and ship-to-target are the normal modes used by tactical forces. In the near future, training exercises and tests will include the ground-to-air mode as more state-of-the-art airfields and ground force air defense systems are developed. The air-to-air mode is used for research and development projects and then only with special permission. Required information is listed below for each case.

6.1.4.1 Air-to-Ground. Determine desired flight profiles. Flight information necessary to perform an evaluation is altitudes, ranges, and directions of the aircraft relative to the target during laser operations. Various terms are used to describe the aircraft direction during ordnance delivery; they include approach track, attack heading, and run-in heading. These headings can be on a single bearing, a range of bearings, and unrestricted approach (360^o). Typical mission profiles are

Toss Delivery, General Profile

Slant Range: 1,800 - 70,000 feet

Altitude: 200 - 2,600 feet

Toss Delivery, Mode A

Slant range: 20,000 - 70,000 feet

Altitude: 200 - 320 feet

Toss Delivery, Mode B

Slant range: 10,000 - 25,000 feet

Altitude: 1,000 - 3,400 feet

Straight and Level Delivery

Slant range: l,800 - 30,000 feet

Altitude: 1,500 -3,300 feet

Dive Delivery

Slant range: 8,500 - 14,000 feet

Altitude: 4,000 - 7,600 feet

 

6.1.4.2 Ground-to-Ground. Determine possible laser locations and direction of laser operations.

6.1.4.3 Ship-to-Target. Determine the possible laser locations, direction of laser operations, and ship headings.

6.1.5 Laser Surface Danger Zone. The LSDZ (also called the buffered laser footprint for airborne and elevated lasers) must be determined using the procedures provided in Paragraphs 6.3, 6.5, 6.7, 6.8, and 6.9.

6.2 Target and Target Area Condition

Careful attention must be paid to the condition of the target and surrounding laser hazard area. Any specular reflectors on or around the laser targets must be either removed or rendered diffuse. Specular reflectors may be rendered diffuse by painting with a flat (non-specularly reflecting) paint. Merely covering a specular reflector is not adequate, because the covering material is usually susceptible to ordnance damage. The position and orientation of any specular reflectors that cannot be removed or rendered diffuse must be noted, so they can be considered during the laser safety evaluation. Generally, specular reflectors larger than .0.5 inch in diameter must be removed from the LSDZ. If this is too restrictive, individual LSOs may refer to the specialists in subparagraph 1.2.2. Target area conditions should be reviewed periodically as determined necessary by local safety authority.

6.3 System Performance

To meet mission requirements, the stability, pointing accuracy, and boresight retention capabilities of a laser rangefinder and designator system must exceed those required for range safety. Described in the following subparagraphs are buffer zones and laser variety.

6.3.1 Buffer Zones. In establishing the laser safety buffer zone for a particular system, a factor of at least five times the demonstrated accuracy of the system is used. This factor has been used to compensate for such factors as untrained operators, adverse environmental factors, and system use at the limits of its capability. These buffer zones for specific systems are addressed in Appendix A, Table A-1.

6.3.2 Laser Variety. If a variety of laser systems with similar capabilities is to be used on the same range, only the worst-case parameters are used in the laser safety evaluation of the range. As an example, the A-6E Target Recognition Attack Multisensor (TRAM), the OV-10D Night Observation System (NOS), and the F-111 Pave Tack systems have similar performance capabilities and may be considered for use on the same range facility. The NOHDs of the systems, as measured in the far field, are 8.1 nautical miles (nmi), 6.1 nmi, and 8.6 nmi. All three systems have been assigned a safety buffer zone of 5 mrad. A range safety evaluation based on an NOHD of 8.6 nmi and a 5-mrad buffer zone would, therefore, allow safe use of any one of the three systems on the range without the confusion of three different sets of restrictions. The system parameters are also adequately similar so the least hazardous systems are not unduly restricted.

6.4 Laser Surface Danger Zone

The LSDZ consists of the target area plus the horizontal and vertical buffer zones (see Figure 6.2) and considers both direct hazards (main beam) and indirect hazards (reflections). The boundaries of the LSDZ depend on which of the two overlapping zones, direct hazard or the indirect hazard, is larger. If there are no specular reflectors on the range and the laser is not a diffuse reflection hazard, there will not be an indirect hazard zone. The direct hazard zone will always exist if laser-to-target distance is less than the NOHD. The LSDZ includes the laser beam plus a buffer zone around the beam to account for laser platform instability. The three types of LSDZs and the dimensions are described in the following subparagraphs.

6.4.1 The total hazard zone is LSDZ area Z or simply the LSDZ. It extends out to the NOHD/NOHD-O or beam backstop and the edges of the laser beam buffer zone.

6.4.2 The area that must be cleared of specular surfaces is LSDZ area S. For ground based lasers that do not project a well defined footprint on the ground around the target (beam and buffer footprint are contained on target), LSDZ area S is usually defined by a circle of radius s (as specified in Appendix A, Table A-1) around the target. For airborne laser operations, area S is the same as LSDZ area Z. For ground based laser operations from elevated platforms where the laser projects a well defined buffer footprint, area S should equal LSDZ area Z. Backstop areas where the energy of the incident beam is capable of producing a specular reflection hazard are considered LSDZ area S.

6.4.3 The diffuse reflection hazard zone is LSDZ area T. It extends to distance t, the diffuse reflection hazard distance, and will only be present for lasers capable of producing a hazardous diffuse reflection which have a distance t associated with them. The LSDZ area T is considered an exclusion zone. No one is allowed in it, and firing lasers at any materials located within this diffuse reflection hazard area must be prohibited. Although a skin hazard can also exist in this area, it is a minor concern compared to the diffuse reflection hazard (see Figure 6-3).

 



Figure 6-2. Laser surface danger zone.



Figure 6-3. LSDZ without and with natural backstop.

6.4.4 The tables in appendixes A, B, and C list the applicable dimensions of the hazard distances for current laser devices. Figure 6-4 provides an example of an LSDZ or laser range danger fan (LRDF) for a training situation. The following paragraphs describe the LSDZ limits.

6.4.4.1 Existing Surface Danger Zones. Existing munitions surface danger zones for direct fire weapons are usually large enough to provide the required horizontal and vertical buffer zones for ground-to-ground laser operations provided the beam is terminated in the impact area (see Figures 6-5 and 6-6).

6.4.4.2 Distance of the Laser Surface Danger Zone. The following combination of NOHD and terrain features must be considered in controlling laser hazards.

6.4.4.2.1 When viewing the collimated beam with a telescope, the hazardous range is greatly increased. For example, a 10-km NOHD would be increased to 80 km for an individual looking back at the laser from within the beam with 13 power optics. Such large amounts of real estate are difficult to control. The solution is to use a backstop behind the target.

6.4.4.2.2 On the ground, this area normally extends to an adequate backstop or the NOHD. Laser operations at targets on the horizon is permitted as long as air space is controlled to the NOHD. In this case, the LSDZ extends downrange to the NOHD in the airspace and to the skyline on the ground as seen from the laser position (see Figure 6-6). Operators and crews will conduct laser operations only at approved targets. Usually, when there are no natural backstops available (for example, mountains), the magnified NOHD-O (O indicates optics) may extend out to extremely long ranges (for instance, 80 km for tank-mounted laser rangefinder (LRF)). This extreme situation would only create ocular hazards if (1) there was a direct LOS to an observer on the ground, and (2) there is a possibility that the observer could be engaged in direct intrabeam viewing with unfiltered magnifying optics.

6.4.4.2.3 Unless the NOHD or NOHD-O has been exceeded, the hazard distance of the laser device is the distance to the backstop. This hazard distance must be controlled. The terrain profile from the laser device's field of view plays a very important role, because the laser presents only a LOS hazard. The optimal use of natural backstops is the obvious key of minimizing laser range control problems.



 

Figure 6.4. Example laser range danger fan/laser surface danger zone.



 

Figure 6-5. Vertical buffer zone.



 

Figure 6.6. Effects of backstops.

 

6.4.4.3 Buffer Zones. The extent of horizontal and vertical buffer zones around the target area, as viewed from the firing area, depends on the aiming accuracy and stability of the laser device. The laser horizontal buffer zones could partially or completely be included in lateral safety or ricochet areas on ranges where the laser is used with live fire weapons. Table A-1, lists buffer zone values for currently fielded equipment.

6.5 Range Facilities Evaluation

6.5.1 Range Location and Access. Range facilities are evaluated in terms of location relative to populated areas, military and civilian industrial sites, and water surface traffic. The methods used to control access to the potential laser hazard area, that is, fences, warning signs, airspace restrictions, and water surface danger areas, must be evaluated for adequacy. The locations of all occupied areas on the range such as control towers must be determined as well as specific environmental factors like the habitat of any endangered wildlife in the range area.

6.5.2 Targets Types. Target areas are evaluated for types of targets currently in position. Vehicular targets, in particular, could have chrome bumpers, windshields, or other flat glass or chrome surfaces. Presence of these types of surfaces could generate a specular reflection when optical radiation is incident to the target. This hazard could even exist if the surfaces were bent or broken because of previous ordnance impacts or explosions. Broken or bent specular surfaces could still have an adequately large flat surface remaining to generate a specular reflection. Unexploded ordnance areas in or surrounding the proposed target area could have an impact on the advisability of policing or masking existing specular surfaces.

6.5.3 Terrain Features. Terrain features on and surrounding the range are evaluated for impact on laser safety. Usable terrain and vegetation backstops are identified and located on maps of the range area. Any mountain peaks outside the range are examined to verify that such obstructions as radio or television towers or park service observation towers do not extend into the laser buffer zone between the laser and the target. This consideration only affect airborne laser systems when active target illumination begins before the aircraft enters the range boundaries.

6.5.4 Access Control. Roads or other access points to the range area should be evaluated to determine the probabilities of non-controlled personnel entering the target area or controlled range areas. Roadblocks should be established and posted at the area where access could occur.

6.5.5 Operations Over Water. Because water can become a flat specular reflector when it is calm, additional precautions are required when firing the laser over water. In most applications, the reflectors contained in Table 6-1 can be either covered or removed, while water cannot always be avoided; therefore, additional precautions are required when firing over water as discussed in Appendix G (see Figure 6-7).

 



Figure 6-7. Example of airborne beam reflection.

20. 6.6 Visual Survey

A visual survey of the range area is often very useful. The survey should be conducted from actual firing locations and target locations. If the target is used for aerial operations, the range evaluator should, whenever possible, perform an aerial fly-over on the proposed or approved laser run-in headings. A pair of binoculars with an angular calibrated reticle can be used to scan the terrain features to estimate the natural buffer area. Suitable areas should be marked on a current map. Do not rely entirely upon the contour lines on the range map, because they may result in an erroneous estimation of the buffer area. Actual targets should be visually inspected for specular reflectors before their insertion on the range to ensure that these surfaces are removed. Conversion of an impact area to a laser range area may require overflights to observe any glints of sunlight reflecting from broken bits of glass or other reflectors laying on the ground.

21. 6.7 Laser Parameters

Laser system parameters may vary greatly with laser location, look angle, support structure and laser characteristics. The effects of these parameters are provided in the following subparagraphs.

6.7.1 In addition to knowing the geometry of the range environment, knowledge of the specific laser system is essential. Perhaps the most important aspect to laser range safety is the assurance that the laser beam is terminated within a controlled area. When the distance to the backstop is less than the NOHD, the backstop determines the absolute hazard distance and the NOHD is of academic value. The buffer zone requirements are based on the pointing accuracy and stability of the system and, therefore, are dependent upon the laser system mounting; that is, a handheld laser system has a larger buffer zone than a tripod mounted system. Some laser systems are designed to be used from a variety of mounting configurations. Table A-1 contains the minimum buffer zone requirements for currently fielded laser systems under their intended mounting configurations.

6.7.2 A controlled area is where the occupancy and activity of those within the area are subject to control and supervision for the purpose of protection from laser radiation hazards. The hazard zone or footprint will be the beam itself plus a buffer zone. This footprint is normally an ellipse. The minor axis depends on the laser-to-target range and the buffer zone angle for that particular laser. The major axis depends upon the altitude of the laser above the target in addition to the requirements for the minor axis. Therefore, the amount of and surface area required to be controlled depends on the elevation of the laser, range to target, and the specific laser system. When necessary, any of these factors can be changed to ensure that the laser beam is terminated within the controlled range boundary; that is, the footprint can be reduced in size by elevating the laser. Thus, either a fairly large area can be controlled which might extend out to the NOHD, or target or laser locations can be selected which provide the required backstop.

23. 6.8 Laser Footprint

Calculate the size of the beam which irradiates the ground or ground-based, sea-based, or airborne target (footprint). Normally, laser beams are circular, diverge equally in all directions, and produce cone shaped beams. The size of the beam depends on the initial beam diameter, divergence, and distance (slant range) from the source. The size of the footprint is the size of the beam plus a buffer zone (see Figure 6.8). For scanning systems, the size of the beam would include all positions in the scan. The shape of the footprint depends on the angle of the beam that intersects the ground. (Slant angle is determined from the range and altitude.) The footprint is determined by buffer angle and size which are described in the following subparagraphs.

6.8.1 Buffer Angle. If the assigned laser buffer angle is 5 milliradians and the beam divergence is less than 0.5 milliradians, use 5 milliradians for the buffered footprint angular width and ignore the beam divergence. This approach will only introduce an error of less than 5 percent. If this evaluation is overly restrictive (requires too much land), a system specific evaluation can be made for each laser system. The appropriate buffer angles for most systems are listed in Appendix A. To calculate a buffered footprint for other systems when the beam divergence is equal to or greater than l milliradian, the footprint will be the buffer angle plus the beam divergence. When the beam divergence is less than l milliradian, the following will apply:

6.8.1.1 If the aiming accuracy for a stabilized laser is unknown, buffered footprint angular width will be 5 milliradians either side of the beam.

6.8.1.2 If the aiming accuracy is known, the buffered footprint angular width will be 5 milliradians, or the absolute value of the aiming uncertainty (in milliradians) plus 5 times the beam divergence at the 1/e (.3679) point, whichever is less, either side of the laser beam. Aiming accuracy should be contained in the system specifications.

6.8.2 Footprint Size. There are at least two approaches used to determine the size of the footprint. If the desired flight profiles are known, then the size of the footprint can be determined from these flight profiles. If the size of the range is the limiting factor, the boundaries of flight profiles can be determined which would keep the footprint within the range. These two approaches can be used independently or, typically, used together to maximize land use and minimize mission impact. The procedures for these two approaches are detailed in Appendix E.

24. 6.9 Other Considerations

6.9.1 Moving Targets or Lasers. A moving target or laser will affect the size of the LSDZ and may indicate that the single pulse NOHD is more applicable than the multiple pulse NOHD, especially when evaluating specular reflections. This range layout must be decided on a case-by-case basis. A common application includes evaluating reflection hazards when the angle of laser operations is rapidly changing, and therefore, the probability of a multiple pulse exposure is small.

Figure 6-8. Examples of the use of natural backstops, buffer zones, and restricted air space.

6.9.2 Operating Outside of Controlled Area. Targets should never be positioned outside the controlled area (including airspace). Airborne lasers should not be operated outside the controlled airspace if the potential for the beam striking an object outside the controlled area exists. If this risk is minimal, consider permitting laser operations from uncontrolled areas under controlled conditions. Ensure the regional Flight Service Center for the Federal Aviation Administration (FAA) and Coast Guard is notified before starting this operation, so they can publish a Notice to Airmen and Mariners. The FAA regulation governing this is 7930.2B, Notices to Airmen (NOTAM). Ground laser systems should never be operated outside the controlled area.

6.10 Range Control Procedures and Recommendations

Laser range safety shall prevent exposure of unprotected personnel from laser radiation in excess of the MPE. This objective can be met by determining where the laser radiation is expected to be, restricting access of unprotected personnel, and removing reflective surfaces from this area.

6.10.1 Target Areas. Recommended target areas are those without specular (mirror like) surfaces. Glossy foliage, raindrops, snow, and other natural objects are not considered to be specular surfaces that would create ocular hazards. Although snow is not considered to be a specular surface, if thawed and refrozen, hazardous reflections can be found, especially at low angles of incidence.

6.10.2 Sanitized Ranges. If the target areas have no flat specular surfaces, range control measures can be limited to the control of the area where the laser beam hits directly.

6.10.3 Laser Operation. Laser devices shall only be directed at safety approved targets and only from approved operating positions or on designated headings and altitudes.

6.10.4 Unprotected Personnel. Unprotected personnel must not be exposed to laser radiation greater than the MPE.

6.10.5 Warning Signs. Local procedures should provide for the placement of laser warning signs at the boundaries of the controlled areas and the access points. This process is normally coordinated between bioenvironmental engineers, industrial hygienists, laser safety officers, or ground safety, ship's safety officer, and the range officer. These signs should be constructed in accordance with MIL-STD-1425. They are also available in the federal stock system (see Figure 4-3). If the hazard zone is within a designated range, access controls must be established.

6.10.6 Eye Wear. Personnel within the LSDZ shall wear laser protective eye wear during laser operations. Eye wear must be approved for the wavelength of the laser system being used and must provide sufficient protection (see Appendix A, Tables A-3 and A-4). If more than one type of laser is used, protective eye wear must provide adequate protection for all wavelengths involved (OD greater or equal to the largest minimum OD required for each wavelength).

6.10.7 Optical Devices. Magnifying daylight optical devices, without attenuation, may be used to view the target only if flat specular surfaces have been removed from the target area. Specular surfaces can be viewed only if appropriate laser safety filters are placed in the optical train of the magnifying optics.

6.10.8 Range Access Restrictions. Access restrictions to the laser range should include consideration of road blocks or gates especially where the range is unmanned.

6.10.9 Laser Demonstrations. Personnel may safely view a diffuse reflection of an otherwise hazardous laser beam from a protected setting as shown on Figure 6-9. The laser-to-target distance is great enough to preclude a hazardous reflection from a dry diffuse target. Infrared viewers or night vision goggles are necessary to view the diffuse reflections from near-infrared lasers. Visible diffuse reflections can be seen with the unaided eye.

Figure 6-9. Supervised laser demonstration for military training.

(Modified from ANSI Z136.1, Figure 2D)

7.1 Instruction

Using the laser range safety evaluation, the range planner/LSO will determine the necessary information to

7.1.1 prepare or modify range laser safety directives,

7.1.2 develop SOP for laser operations,

7.1.3 brief personnel involved in laser operations to provide an understanding of the hazards of specific devices and to allay unfounded fears, and

7.1.4 prescribe the personal protective equipment to be used.

7.2 Directives

The laser range safety evaluation should be used to review and to ensure overall range safety regulations are current. Regulations should be developed or updated as necessary to take into account new laser systems, operating areas, and targets.

7.3 Standard Operating Procedures

The SOPs for specific laser devices should inform laser users of the potential hazards from the laser devices under their control during laser operation. Checklists for evaluating SOP are provided in Appendix F. An SOP should be prepared concerning procedures for a presweep of the range before a laser operation to ensure unprotected personnel are not in the target area and to maintain radio communications.

7.4 Safety Briefing

In addition to instructions on particular devices or simulators, training material required for classroom instructors and range personnel should include.

7.4.1 principles of reflection or refraction of light,

7.4.2 hazards of laser beams to humans and misconceptions about laser effects,

7.4.3 safety standards or operational control procedures, and

7.4.4 preparation of range areas for laser use (that is, ensure personnel have been alerted to the laser hazard and have covered, removed, or avoided the firing at specular surfaces).

7.5 Protective Equipment

Eye protection requirements are listed in Appendix A, Table A-3.

7.6 Systems Briefings

Laser indoctrination should be provided at the same time as the basic weapons systems instruction to students taking advanced individual training and to officers taking basic courses. The classroom instructors must be knowledgeable in operator and crew aspects of laser safety. Reference publications on subject lasers should be readily available. The instruction presented should be at the user level. (Complex scientific data or terminology should be avoided.) A training film, if available, should be included in the instruction program. Hazard data for lasers as incorporated into the technical manual on the related weapon system or on the laser component should be stressed. Proper channels for obtaining professional safety and medical assistance should be addressed during indoctrination.

1.0 Scope

This appendix provides safety information for currently fielded laser fire control systems.

2.0 Fire Control Laser Safety Features

Fire control laser systems are laser rangefinders (LRFs) and laser designators (LDs). These laser systems can be far more harmful to the eye than laser training devices such as MILES and Air-to-Ground Engagement System/Air Defense (AGES/AD) laser simulators. Consequently, fire control lasers require control measures to prevent permanent blindness to an unprotected individual viewing the laser system from within the laser beam. A sample list of control measures for operators of fire control lasers is provided in Appendix H.

2.1 Ruby LRFs. The ruby LRFs on the tanks are the most hazardous lasers to the eye at close range. These lasers not only pose a hazard while viewing the laser from within the direct beam, but also from viewing the diffusely reflected laser radiation. The distance t is from the laser within the laser beam path in which there is both a skin hazard and diffuse reflection hazard. Distance t represents the range to be cleared in front of the tank.

2.2 Distance S. The distance s was established to prevent specular or collimated reflections from flat glass and other flat and smooth surfaces which might leave the controlled range area. This is the radial distance away from targets out to which flat specular reflectors must be cleared. For fixed wing aircraft, the entire buffered laser footprint must be cleared of specular reflectors. A specular reflector is one that is so smooth that a person can see an image in it. A curved specular reflector does not create a significant risk to individuals at typical training distances from a target.

2.3 Current Laser Safety Summary. Tables A-1 and A-2 summarize current laser safety information pertaining to the most common fire control laser systems likely to be encountered. The NOHD for unaided viewing and while viewing the beam through an optical instrument such as a pair of binoculars (NOHD-O), are listed in Table A-1. The importance of NOHD is often overvalued, because the laser beam is normally required to be terminated in a controlled area and the distance to the backstop defines the absolute hazard distance.