Appendix C C-3 C.2. Example 1: All Wavelengths within the Same Row of MPE Table Given a continuous wave RGB laser emitting 8W of 633 nm red, 4W of 532 nm green, and 8W of 445 nm blue in a single “white-light” beam of 1 mrad divergence, find the MPE, total power, and slant range NOHD.
• Consult Table 2 to determine if all wavelengths are within a single row.
• Since all three are within a single row (400 nm to 700 nm), the MPE for all wavelengths is 2.6 mW/cm2.
• Enter “2.6” in 12b and on the separate document described earlier in this appendix.
• Because all wavelengths are in the same row, have the same divergence, and have the same MPE, add the power of the individual wavelengths together to determine the total power of 20W.
• Using Equation 70-1.2 from section A.16.2.1, the calculated NOHDSR for a 20W, 1 mrad beam is 3246 ft.
• Enter 3246 ft in the slant range column of cell 14a and on the separate document.
C.3. Example 2: Wavelengths in Different Rows of the MPE Table The wavelengths in this example represent different hazards (some retinal and some corneal).
Given a multiple-wavelength CW laser with a single aperture whose beam combines 1W of 532 nm green and 2W of 633 nm red (both with a 1 mrad beam divergence), 10W of 1064 nm infrared (with a 3 mrad beam divergence), and 20W of 1540 nm infrared (with a 1 mrad beam divergence), find the slant range NOHD.
• Consult Table 2 to determine if all wavelengths are within a single row.
• Since not all wavelengths are in the same row, group the wavelengths by those wavelengths within the same row.
NOTE: Grouping by row is only valid when the wavelengths in the same row also have the same divergence. See Example 3 as an example where wavelengths within the same row have different divergences.
o The 532 nm and 633 nm wavelengths fall within the same Table 2 row for 400 nm to 700 nm and they have the same divergence (1 mrad).
▪ There is a total (1W + 2W) of 3W of power for the two wavelengths within this row’s range.
▪ The MPE for this row is 2.6 mW/cm2.
Appendix C C-4 ▪ Using Equation 70-1.2 from section A.16.2.1, the calculated NOHDSR for a 3W, 1 mrad beam is 1257 ft.
o The 1064 nm wavelength falls within the Table 2 row for 1050 nm to 1150 nm.
▪ There are 10W of power for the single wavelength within this row’s range.
▪ The MPE for this row is 12.75 mW/cm2.
▪ Using Equation 70-1.2 from section A.16.2.1, the calculated NOHDSR for a 10W, 3 mrad beam is 345 ft.
o The 1540 nm wavelength falls within the Table 2 row for 1500 nm to 1800 nm.
▪ There are 20W of power for the single wavelength within this row’s range.
▪ The MPE for this row is 4000 mW/cm2.
▪ Using Equation 70-1.2 from section A.16.2.1, the calculated NOHDSR for a 20W, 1 mrad beam is 83 ft.
• Determine which wavelengths are retinal hazards (400 nm to 1320 nm) and which wavelengths are corneal hazards (<400 nm or >1320 nm).
o The 532, 633, and 1064 nm wavelengths are retinal hazards: Use Equation 70-
1.14 to calculate the combined retinal slant range NOHDSRC(Retinal).
NOTE (Rationale): The combined hazard from both wavelengths is greater than either individual wavelength.
𝑁𝑂𝐻𝐷𝑆𝑅𝐶(𝑅𝑒𝑡𝑖𝑛𝑎𝑙) = √(12572) + (3452) = √1580049 + 119025 = √1699074 = 𝟏𝟑𝟎𝟒 𝐟𝐭 o The 1540 nm wavelength is a corneal hazard.
▪ Since this is the only wavelength in this range, it is not necessary to use Equation 70-1.14.
▪ If there were more than one wavelength, repeat Equation 70-1.14 to calculate NOHDSRC(Corneal).
▪ Using Equation 70-1.2 from section A.16.2.1, the calculated NOHDSR for a 20W, 1 mrad beam is 83 ft.
• Determine which slant range NOHD is longer.
o Compare the combined slant range NOHD of the retinal hazard (1304 ft) and corneal hazard (83 ft) wavelengths to determine which combined slant range NOHD is longer.
Appendix C C-5 o In this example, the NOHDSRC for the retinal hazard wavelengths is the longer value.
• Record all information that informed the calculations and determination on the separate document.
o For this example, list the slant range NOHD for each wavelength or group of wavelengths, combined slant range NOHD for the retinal hazard wavelengths, and the slant range NOHD for the corneal hazard wavelength.
o Delineate (e.g., circle, bold, or underline) the longer NOHD: “1304 ft retinal, 83 ft corneal” on the separate document.
• In the MPE row of section 12b of the form, enter “N/A – multiple wavelength ranges.”
• In the slant range column of cell 14a, enter the retinal and corneal NOHDSRC values and delineate (e.g., circle, bold, or underline) the longer NOHDSRC: “1304 ft retinal, 83 ft corneal.”
C.4. Example 3. Wavelengths in the Same Row of an MPE Table with Different Divergences Given a multiple-wavelength CW laser with a single aperture whose beam combines 1W of 633 nm red (with a beam divergence of 1 mrad) and 1W of 532 nm green (with a beam divergence of 2 mrad), find the slant range NOHD.
• Consult Table 2 to determine if all wavelengths are within a single row.
• While the wavelengths of both beams fall within the same row of Table 2 (400 nm to 700 nm), they have different divergences. Therefore, proponents cannot group these wavelengths and must calculate the NOHDSR of each wavelength separately.
• For the 633 nm beam, the MPE is 2.6 mW/cm2 and the divergence is 1 mrad.
o Using Equation 70-1.2 from section A.16.2.1, the calculated NOHDSR for a 1W, 1 mrad beam is 726 ft.
• For the 532 nm beam, the MPE is 2.6 mW/cm2 and the divergence is 2 mrad.
o Using Equation 70-1.2 from section A.16.2.1, the calculated NOHDSR for a 1W, 2 mrad beam is 363 ft.
• Because both wavelengths in this example are in the retinal hazard range of 400 nm to 1320 nm, there is no need in this example to consider a corneal hazard.
• Use Equation 70-1.14 to calculate the NOHDSRC.
𝑁𝑂𝐻𝐷𝑆𝑅𝐶 = √(7262) + (3632) = √527076 + 131769 = √658845 = 𝟖𝟏𝟐 𝐟𝐭
Appendix C C-6
• Record all information that informed the calculations and determination on the separate document. For this example, list the slant range NOHD for each wavelength and the combined slant range NOHD (812 ft) for the two wavelengths.
• In the MPE row of section 12b of the form, enter “2.6” (this can be done because all wavelengths in the example multiple-wavelength laser beam have the same MPE).
• In the slant range column of cell 14a, enter the NOHDSRC of 812 ft.
iv Notes for Equation 70-1.14:
• Accounts for the wavelengths and divergences of each beam in a multiple-wavelength laser beam.
• Accounts for multiple-wavelength laser beams where some wavelengths are CW and some are pulsed (single or repetitively).
• Equation is valid as long as each squared slant range NOHD – (NOHDSR)2 – represents the NOHD of one or more wavelengths with the same MPE, the same divergence, the same output mode (single pulse, repetitively pulsed, or continuous wave), and the wavelengths are within the same hazard range (either retinal or corneal).
• Examples:
o Equation valid: Mixed beams where one wavelength may be pulsed and another is continuous wave, or where one wavelength may have a different divergence than another within either the retinal or corneal hazard range.
o Equation invalid: NOHDs include wavelengths from different (retinal or corneal) hazard ranges.
• One must use Equation 70-1.14 to first determine the NOHDSRC of all wavelengths that are retinal hazards (400 nm to 1320 nm), then to separately determine the NOHDSRC of all wavelengths that are corneal hazards (<400 nm or >1320 nm). FAA will use the longer of the two, combined wavelength NOHDs (NOHDSRC) as the eye protection distance for aeronautical review.
Appendix D Appendix D. Depictions of Airspace Flight Zones and Graphic Examples
LASER FREE ZONE <50 nW/cm' →5000 ft
- 3NM → 5000 ft 2NM 2NM 2NM 3NM —→4 2NM → - 2NM →* - 3NM 2NM
AIRPORT REFERENCE POINT 2NM 3NM → 5000 ft|
AIRSPACE FLIGHT ZONES **SENSITIVE FLIGHT ZONE 100 pW/cm2
CRITICAL
FLIGHT ZONE 5 pW/cm2 →
AIRPORT
REFERENCE POINT 10NM ** To be determined by FAA evaluation and/or local airport operations.
D-1
Appendix D
AIRSPACE FLIGHT ZONES **SENSITIVE FLIGHT ZONE 100 uW/cm'
CRITICAL FLIGHT ZONE 5 pW/cm?
LASER FREE ZONE 50 nW/cm' ** ** 3NM 2NM 2NM 3NM 10NM 10NM
AIRPORT REFERENCE POINT (ARP) *Runway length varies by airport. Attitudes in AGL based on established airport elevation.
** To be determined by FAA evaluation and/or local airport operations.
AIRSPACE FLIGHT ZONES **SENSITIVE FLIGHT ZONE <100 pW/cm?
*Not to Scale
CRITICAL FLIGHT ZONE <5 pW/cm?
10,000 AGL
LASER FREE ZONE <50 nW/cm?
2,000 AGL 3NM " 2NM - 2NM "3NM -10NM -10NM- Airport Reference Point (ARP) ** To be determined by FAA evaluation and/or local airport operations.
D-2
Appendix D
VISUAL INTERFERENCE DISTANCES Irradiance is 100 pW/cmг SZED Irradiance is Irradiance is 5 pW/cm? 50 nW/cm2 ¡CZED LFED Laser Source Flash- Glare No Blindness Hazard Hazard Hazard NOTE: Visual distraction may occur at any distance D-3
Appendix E E-1 Appendix E. FAA Service Center Information FAA Service Center and Corresponding Service Area boundaries align with Air Route Traffic Control Center airspace boundaries. FAA encourages proponents to contact the service centers with any question relating to submitting FAA Form 7140-1.
If emailing the submission to an FAA service center, please include the name, location, and date of the proposed operation in the subject line to assist service center personnel with their review and timely response.
FAA Service Center States and Territories Eastern Service Center Attn: Manager, Operations Support Group Eastern Service Center, AJV-E2 1701 Columbia Ave.
College Park, GA 30337
9-ATO-ESA-OSG-Lasers-Searchlights@faa.gov Alabama (portions), Arkansas (portions), Connecticut, Delaware, District of Columbia, Florida, Georgia, Illinois (portions), Kentucky (portions), Louisiana (portions), Maine, Maryland, Massachusetts, Mississippi (portions), Missouri (portions), New Hampshire, New Jersey, New York (portions), North Carolina, Oklahoma (portions), Pennsylvania (portions), Puerto Rico, Rhode Island, South Carolina, Tennessee (portions), Vermont, Virginia (portions), West Virginia (portions) Central Service Center Attn: Manager, Operations Support Group Central Service Center, AJV-C2 10101 Hillwood Parkway Fort Worth, TX 76177
9-ASW-Operations-Support-Lasers@faa.gov Alabama (portions), Arizona (portions), Arkansas (portions), Colorado (portions), Illinois (portions), Indiana, Iowa, Kansas (portions), Kentucky (portions), Louisiana (portions), Michigan, Minnesota, Mississippi (portions), Missouri (portions), Nebraska (portions), New Mexico (portions), New York (portions), North Dakota (portions), Ohio, Oklahoma (portions), Pennsylvania (portions), South Dakota (portions), Tennessee (portions), Texas, Virginia (portions),West Virginia (portions), Wisconsin Western Service Center Attn: Manager, Operations Support Group Western Service Center, AJV-W2 2200 S 216 Street Des Moines, WA 98198
9-ATO-WSA-OSG-Lasers@faa.gov Alaska, Arizona (portions), California, Colorado (portions), Hawaii, Idaho, Kansas (portions), Montana, Nevada, New Mexico (portions), North Dakota (portions), Northern Mariana Islands, Oregon, South Dakota (portions), Utah, Washington, Wyoming
Appendix E
WESTERN SERVICE AREA
CENTRAL SERVICE AREA
EASTERN SERVICE AREA E-2
Appendix F F-1 Appendix F. Glossary Afterimage – A reverse contrast shadow image left in the visual field after an exposure to a bright light (e.g., flashblindness from a camera flash) that may be distracting and disruptive, and may persist from several seconds to several minutes.
Center for Devices and Radiological Health (CDRH) – An office of the FDA concerned with enforcing compliance with the Federal requirements for laser products including laser light shows.
Demonstration – Any laser product designed or intended for purposes of visual display of laser beams, for artistic composition, entertainment, or advertising display (see 21 CFR 1040.10(b) 13). Any demonstration laser in excess of 5 mW requires a variance from the CDRH.
Distraction – The redirection of attention from primary tasks due to a sudden exposure to a bright light source. While distraction technically does not interfere with vision, redirection of attention is a visually triggered hazard. For this reason, distraction is classified as one of the three primary visual interference hazards (along with glare and flashblindness/afterimage).
Divergence – The increase in the diameter of the laser beam with distance from the exit aperture. Divergence is an angular measurement of the beam spread, expressed in milliradians (mrad). In laser safety calculations, divergence is defined at the points where the irradiance is 37% (1/e) of the peak irradiance.
Flashblindness – A temporary visual interference effect that persists as an afterimage after the source of illumination has ceased. Flashblindness is not associated with biological damage.
Flight zones – Airspace areas where laser light levels may be restricted to avoid visual interference effects (LFZ, CFZ, SFZ) or are unrestricted when aircraft are not present (NFZ). A given flight zone may not be continuous or concentric with other flight zones. There are four types of flight zones, ordered here from most to least restrictive.
Laser Free Zone (LFZ) – Airspace zone where the level of laser light is restricted to 50nW/cm2 or less, a level that should not cause any visual distractions or disruptions.
Critical Flight Zone (CFZ) – Airspace zone where the level of laser light is restricted to 5 µW/cm2 or less, a level that should not cause veiling (obscuring) glare.
Sensitive Flight Zone (SFZ) – Airspace zone where the level of laser light is restricted to 100 µW/cm2 or less, a level that should not cause flashblindness or afterimage effects. This is a locally defined area beyond the Critical Flight Zones that authorities (e.g., FAA, local departments of aviation, or military) have identified as requiring protection from visual interference effects.
Normal Flight Zones (NFZ) – All airspace not defined by the aforementioned zones where any laser light (visible or non-visible) is restricted to less than the MPE. In the NFZ, any visible laser light that may cause visual interference is not expected to be hazardous.
Appendix F F-2 Glare – A temporary disruption in vision caused by the presence of a bright light (for example, an oncoming car’s headlights) within an individual’s field of vision. Glare is not associated with biological damage. Its effect only lasts as long as the light source is present within the individual’s field of vision.
Horizontal Distance – The maximum distance along the ground where an angled (elevated) laser beam may be an eye hazard or a visual interference hazard.
Irradiance – The intensity of the laser beam over a given area, expressed as power per unit area, e.g., milliwatts per square centimeter (mW/cm2) or watts per square meter (W/m2). Irradiance is used for power (watts) while radiant exposure is the same concept for energy (joules).
Joule (J) – The International system unit of energy, equal to the work done when a current of one ampere is passed through a resistance of one ohm for one second.
Laser – An acronym for Light Amplification by Stimulated Emission of Radiation. A laser is a device that produces an intense, directional, coherent beam of visible or invisible light.
Laser manufacturer – A term that refers to persons who make laser products, including those who are engaged in the business of design, assembly, or presentation of a laser light show.
Laser operator – A person in control of the operation of a laser system. A laser operator should be a knowledgeable person, present during laser operation, and given authority to operate the laser system in compliance with applicable safety standards, subject to direction or recommendations of the Laser Safety Officer.
Laser Safety Officer (LSO) – A designated person who has authority and responsibility to monitor and enforce the control of laser hazards and affect the knowledgeable evaluation and control of laser hazards.
Local Laser Working Group (LLWG) – A group convened as necessary to assist the regional air traffic division in evaluating the potential effect of laser emissions on aircraft operators near the proposed laser activity.
Maximum Permissible Exposure (MPE) – The level of laser radiation to which a person may be exposed without hazardous effect or adverse biological change in the eye or skin. The MPE value varies based on the beam’s characteristics (e.g., wavelength, irradiance, or radiant exposure level, or continuous wave or pulsed), exposure duration, and body part exposed to the light (eye or skin). Since the eye is the most sensitive to laser injury, this document uses eye MPE values. In general, MPE is expressed in watts or joules per square centimeter.
Milliradian (mrad) – A measure of angle used for beam divergence. A milliradian is 1/1000 of a radian, or approximately 1/17th of a degree. There are 6283.185 milliradians in a circle.
Protection distances – Distances along the laser beam to a point where the laser is no longer considered an eye injury hazard (NOHD), or to where it is no longer considered a hazard for flashblindness/afterimage (SZED), glare (CZED), or to where it is no longer expected to cause distraction (LFED). FAA is concerned with the NOHD for any laser in navigable airspace, whether it emits a visible or non-visible beam. FAA is only concerned with the other three distances when lasers with visible wavelengths (between 400 nm and 700 nm) are emitted in navigable airspace. There are four protection distances (NOHD, SZED, CZED, and LFED), defined as follows.
Appendix F F-3 Nominal Ocular Hazard Distance (NOHD) – The protection distance from the laser source to where the beam irradiance or radiant exposure falls below the MPE for human eyes. Within the NOHD, potential eye injury may occur. Beyond the NOHD, the beam irradiance or radiant exposure would be less than the eye MPE and is not expected to cause eye injury.
Sensitive Zone Exposure Distance (SZED) – The visual interference distance from the laser source to where the beam irradiance is less than 100 µW/cm². Within the SZED, potential eye injury and temporary flashblindness with resulting afterimages may occur. Beyond the SZED (beam irradiance less than 100 µW/cm²), flashblindness or afterimages are not expected to occur.
Critical Zone Exposure Distance (CZED) – The visual interference distance from the laser source to where the beam irradiance is less than 5 µW/cm². Within the CZED, potential eye injury, flashblindness/afterimages, and veiling (obscuring) glare may occur.
Beyond the CZED (beam irradiance less than 5 µW/cm²), glare which obscures objects is not expected to occur.
Laser-free Exposure Distance (LFED) – The visual interference distance from the laser source to where the beam irradiance is less than 50 nW/cm². Along the beam from the laser source to the LFED, potential eye injury, flashblindness/afterimages, veiling glare, and distraction may occur. Beyond the LFED (beam irradiance less than 50 nW/cm²), the laser light is similar in brightness to most other bright city and airport lights seen at night and is not expected to cause additional distraction.
Radiant exposure – The intensity of the beam over a given area expressed as energy per unit area, generally joules per square centimeter (J/cm2). Radiant exposure is used for energy (joules) while irradiance is the same concept for power (watts).
Safety observer – A designated person who is responsible for monitoring the safe operation of a laser and who can immediately terminate the laser beam if necessary to ensure safety. Normally, a safety observer will view airspace near a laser beam to identify any potentially unsafe condition.
Slant range – The distance directly along the beam (e.g., “slant range” does not vary depending on beam elevation angle).
Terminated beam – A laser beam that ends on a surface and is blocked from continuing into navigable airspace.
Unterminated beam – A laser beam that is directed or reflected into navigable airspace.
The proponent should provide sufficient evidence to FAA that users of the National Airspace System are not adversely affected by the beam.
Variance – FDA approval for a laser manufacturer or operator to vary from compliance with 21 CFR § 1040.11 by providing an equivalent level of safety via alternate means.
Vertical Distance – The maximum altitude above the ground where an angled (elevated) laser beam may be an eye hazard or a visual interference hazard.
Watts – A unit of measurement associated with power output. The wattage of a laser system or limit of laser power in a flight zone is often expressed as a milliwatt (mW), microwatt (µW), or nanowatt (nW). One watt is one joule per second.