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Development of ANSI Z136.6. Wesley J. Marshall US Army Center for Health Promotion and Preventive Medicine Chair, Analysis and Applications ANSI Z136 Committee. Military Standard 1425. DoD exemption 76EL-01DOD Released DOD from all Requirements of 21 CFR 1040
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Development of ANSI Z136.6 Wesley J. Marshall US Army Center for Health Promotion and Preventive Medicine Chair, Analysis and Applications ANSI Z136 Committee
Military Standard 1425 • DoD exemption 76EL-01DOD Released DOD from all Requirements of 21 CFR 1040 • Alternate Product Performance Requirements for Military Systems Published in 1983 and revised in 1991 • Acquisition Reform 1994 by Secretary of Defense William Perry Forbids use of Military Standards for Procurement • Use of Public Consensus Standards Instead
Light Show Problem • Laser Light Shows Sometimes Interfere with Safe Operation of Aircraft • In Las Vegas, Nevada, over 50 incidents Occurred within a Two-Year Period • Prompted FDA to withdraw Variances for Laser Light Show Operators in Las Vegas in Late 1995 • Develop Guidance for Laser Light Shows
ANSI Z136.1 • Rules for Classification and Hazard Evaluation • Maximum Permissible Exposure • Control Measures • Use of Laser Devices • Design of Laser Systems (labeling) • Nothing Specific for Military Laser Devices • Examples of Applying the Rules to Hazard Evaluation of Systems • Does not Include Visual Effects from Lasers and Secondary Hazards from Glare or Flashblindness
Document History • FAA Order 7400.2D (Sept. 16, 1993) • Recommended Interim Guidelines (RIGS) to Supplement FAA Order 7400.2D, Chapter 34 (January 26, 1995) • Organizations Involved in Development • FAA, SAE G-10T Flight Safety Committee, Airline Pilots Association, FDA, International Laser Display Association • ANSI Z136.6 started in April 1995 and Published in August 2000
ANSI Z136.6 Outdoor Laser Use • Contains Information from Mil Std 1425A • Addresses Light Show Problem by Including Exposure Levels Below the MPE that may cause Secondary Hazards • Control Measures and Methodology for Use of Lasers Outdoors • Useful Information and Examples
Laser Use in Airspace • Aircraft • Commercial Airlines • Private Planes • Helicopters • Laser Light Shows • Scientific Projects
Visual Interference Effects • Flashblindness • Disability Glare • Startle • Dazzle
LASER HAZARDS with DISTANCE VISUAL EFFECTS Hazard Distance Laser Startle Afterimage Potential Retinal Injury Glare
Daylight Glare Effects • Through Optical Site • Unaided
Military Laser Protection for Pilots 2 Notch Night Spectacles or 3 Notch Day Spectacles 3 Notch Day Visors 2 Notch Night Visors HGU-56/P Format: Both Visors Apache IHADSS Format: 2 Notch Clear Laser Eye Protection (CLEPIR) AF Spectacle Use with HGU-56/P Compatible with NVGs
The Tradeoffs of Laser Eye Protection • Reduced visibility of color displays and warning lights! • Visibility performance • Blending of surface colors • Loss detail (acuity) • Loss of depth perception • Adaptation • Not Practical for Civilian Pilots and Aircraft
10 NM 10 NM 2 NM 5 NM 5 NM 2 NM Laser-free Zone CRITICAL ZONE Aircraft Flight Zones
Flight Zones • Critical • 10 nautical miles from runways • 10,000 feet above ground level • Laser-Free • 5 nautical miles from runway • 2,000 feet above ground level Critical LaserFree
Zones Normal Flight Zone Sensitive Zone Critical Zone Laser-Free Zone Effective Irradiance 2.5 mW/cm2 100 W/cm2 5 W/cm2 50 nW/cm2 Flight Hazard Zones and Visual Interference Levels
Safety Program Management • Laser System Management Organization • Laser Safety Officer • Laser Safety Specialist • Laser Operator • Safety Observer SOP
Laser Safety Methodology • Consider: • Operational Volume & Hazard Distances • Local Airports and Hazard Zones • Air Traffic Patterns and Densities • Relative Risk of Lasers and Airspace • Choose Preventive Methods • Boresight radar or FAA data • Safety Observers • Infrared Camera System
Definitions • outdoors. In this standard, a location for a laser where the insertion of a mirror into the output beam path could create a specular reflection that extends indefinitely. However, if the reflected beam thus created does not exceed the MPE anywhere along the beam path, or one of the visual interference levels within the corresponding visual interference zone, then the location need not be considered as outdoors.
More Definitions • buffer angle. An angle added to the beam divergence or intended laser projection field in order to ensure a protection zone. • buffer area. The projection of the buffer zone around a target, when the ground serves as the beam backstop.
Another Definition • operator controlled space. An area on the ground or volume of airspace where the operator has the capability and responsibility for immediately terminating laser operation when a potentially hazardous situation arises. • Generally NOHD < 100 m (700 m Optics)
Diffuse Hazard Pulsed Lasers in Retinal Hazard Region.
Atmospheric Attenuation ( = 5 10‑7 cm‑1)
Measurement of Divergence • Two-Point Aperture Method • Long Focal Length Lens Method • Knife-Edge Technique • Beam Profiler Method
Conclusion • The ANSI Z136.6 contains Useful Information and Tables • In Revision for Third Edition • SSC-6 Committee Continues to Provide Useful Information in Easy to Understand Language