Weather Radar Exposure

[Control Abnormality]

Hey,
Does anyone know what the dangers are of exposure to airborne weather radar on the ground?
After a walk around I found the radar had been left on and tilted downwards so I would have been exposured to it for sometime during my checks at the front of the aircraft, as would other ground crew.
How much exposure is dangerous?
Is there anything I should do or is a one off like this not likely to be a problem.
Any info would be appreciated.

[tom775257]

If it is a vaguely modern WX radar, unless you are hugging the radome with it on for long periods of time you should be fine. The safe distance is about 1.5 metres with a modern unit AFAIK:

Anyhoo to quote Rockwell collins:

<<RADIATION HAZARDS
To provide a practical safety factor, the American National Standards
Institute has specified a maximum level of 10 mw/cm2 for personnel
exposure of 6 minutes or longer to radar antenna electromagnetic
radiation. The exposure time is limited to the amount of time within the
antenna pattern during each sweep.
In 1980, Collins engineering personnel measured the radiation
emissions of an actual weather radar system on the flight line. A
General Microwave radiation hazard meter (Model 481B) was used to
measure the emitted radiation. It was placed 1.5 feet in front of the
radar’s flat-plate antenna during normal operation with the radome
removed. System range was set to 320 NM to provide the maximum
pulse width. Under these conditions, the maximum power density meter
reading was 0.3 mw/cm2.
In a similar fashion, the United States Air Force’s Armstrong Laboratory
measured the power density of the military version of the windshear
radar and found the highest power density level to be 0.13 mw/cm2.
The Collins WXR-2100 radar system falls well below the 10 mw/cm2
standard. However, it should be noted that there is some disagreement
that the 10 mw/cm2 standard is low enough. Microwave ovens represent
a more public safety concern and their leakage standard has been set
at 4 mw/cm2. The WXR-2100 power density is half or less than that
of the microwave oven standard.
N NOTE
Some sources suggest that any radiation exposure can be harmful,
especially long term. Each airline must make their own decision on
this, as exposure to radiation is occasionally cited by an employee
as a cause of some physical injury.>>


etc.etc. shouldn't be an issue

[Roger Dixon]

Yep, true insofar as it goes. Problem is that permissible microwave exposure levels - ANSI and others - use internal body tissue heating as the medical end-point. This is being found to be an inadequate criterion, as there are other more subtle effects, such as possible chromosome and neural injury, quite apart from the thermal criterion.

Roger Dixon
Industrial Hygienist

[skyrider2001]

i have the same questions, as it also might happened to me and now i am concered ... i still see the risk for us as pilots, because walking on the aprons the risk are quite high that it can happen again.

with what dosis you can compare an exposure during walkaround? e.g radiation?
as it should be OFF on ground in order no to harm other people, i found it hard to believe that there is only a minimal danger out of it.

experts please feel free to share you knowledge! many thanks.
:confused: :confused: :confused: :confused: :confused:

[skyrider2001]

nowbody want to shed up lights here? it is mainly for A320/A340 aircraft types.

[AnthonyGA]

Most people think of cancer or radiation poisoning when they hear "radiation." However, these hazards exist only for ionizing radiation of extremely high frequency (x rays, cosmic rays, gamma rays, hard ultraviolet), and not non-ionizing radiation at the far lower frequencies used for radar systems and microwave ovens.

The effect of radiation from radars and microwave ovens is mainly diathermy—that is, its main effect on human tissue is to heat it up, just as a microwave heats up food. The degree of heating depends on the frequency and intensity of the radiation. Excessive heating can cause tissue damage and degenerative changes, but not cancer or genetic damage. (Cancer and genetic damage generally require that molecules and atoms be torn apart, which non-ionizing radiation like radar isn't strong enough to do.) In rare cases of direct exposure to microwaves from ovens (obtained by disabling the interlocks on the doors), cases of internal burns have been recorded. Also, exposure to intense microwave/radar radiation can cause cataracts in the eyes, because they are very sensitive to heating, since they are not directly cooled by blood circulation (the same thing that happens to the white of an egg when it is fried).

The long-term effects of low-level exposure to microwave and radar radiation have not been quantified or identified to any extent, and remain the subject of speculation. It seems logical and prudent to avoid exposure to weather or other radar to the extent possible, but occasional exposure probably won't have any measurable effect.

I'm reminded of one of my relatives, who worked on very high-power defense radars many decades ago. He and his buddies found it amusing to sweep the radars across office buildings because they were powerful enough to light fluorescent lamps in the buildings, and they sometimes stood in front of feed horns of the radar systems with lamps in their pockets that would light up. The radars could also set off old-style one-use flashbulbs by inducing currents in them. Despite the obvious heavy exposure to radar radiation that this all implies, neither he nor any of his buddies has ever suffered any ill effects, and after sixty years, if something were going to show up, it would have done so by now.

Note that using a cell phone exposes you to the same type of radiation used by radar and microwave ovens.