194
17 Medical Response
medical responders at the scene face the same risks, including the risks of secondary
attacks aimed at them, that are faced by any other emergency responders [33].
Having said that, responders should also understand that it might not be necessary
to move a person all the way to the perimeter of the Hot Zone; in some cases it might
only be necessary to move a few or several meters away from a source in order to
reduce radiation dose rates to levels that will permit a longer stay time (remember,
doubling one’s distance from a source will reduce dose rates—and increase stay
times—by a factor of four). Accordingly, it might be possible to move a person just a
few meters, stabilize them in this location, and then evacuate them to the perimeter.
Once the patient has been stabilized medically the on-site medical personnel
must do their best to balance medical needs versus radiological concerns. Those who
urgently require medical attention must be transported immediately to a hospital to
receive this care, even if they are contaminated. If the medical condition permits,
however, the patient should be given whatever decontamination or contamination
control measures are possible without putting them at risk. Decontamination or
contamination control measures can include:
• Removing outer clothing
• Decontamination (wet, dry, or “moist”)
• Dressing patient in contamination control outfit over their clothing
• Wrapping with blankets or sheets.
How far to reach an area with a safe radiation dose rate?
Arriving at the scene of a bombing about 30 min after an explosion was reported
the initial entry identifies a badly injured person at a distance of about 1 m from
a radioactive source. Your radiation detector alarms at a distance of about 30 m
from the source, indicating a dose rate of 10 mGy h
−1 . Using the inverse square
law, dose rate at a distance of 1 m will be higher by a factor of 30
2 , or about
9 Gy h
−1 . At that dose rate, a person will receive a fatal dose of radiation in
less than one hour.
Thirty minutes after the attack, victim has already received a dose of 4.5 Gy
and taking 15 min to stabilize the victim in place is likely to expose them to
a cumulative dose high enough to be potentially fatal, and you will receive a
dose high enough to cause severe radiation sickness. At the same time, their
injuries are potentially severe and you judge that they are unlikely to survive
evacuation to the perimeter (100 m away) without being stabilized. How far
do you need to move them so that they can be stabilized without putting them
at risk from radiation exposure?
If your goal is to keep the total radiation exposure to less than 5 Gy then
they need to be moved to a distance at which they will receive 0.5 Gy in 15 min,
which is a dose rate of 2 Gy h
−1 .
Reducing the dose rate from 9 to 2 Gy h
−1 requires reducing the exposure
rate by a factor of 4.5. Since dose rate drops with the square of distance, the
17 Medical Response
medical responders at the scene face the same risks, including the risks of secondary
attacks aimed at them, that are faced by any other emergency responders [33].
Having said that, responders should also understand that it might not be necessary
to move a person all the way to the perimeter of the Hot Zone; in some cases it might
only be necessary to move a few or several meters away from a source in order to
reduce radiation dose rates to levels that will permit a longer stay time (remember,
doubling one’s distance from a source will reduce dose rates—and increase stay
times—by a factor of four). Accordingly, it might be possible to move a person just a
few meters, stabilize them in this location, and then evacuate them to the perimeter.
Once the patient has been stabilized medically the on-site medical personnel
must do their best to balance medical needs versus radiological concerns. Those who
urgently require medical attention must be transported immediately to a hospital to
receive this care, even if they are contaminated. If the medical condition permits,
however, the patient should be given whatever decontamination or contamination
control measures are possible without putting them at risk. Decontamination or
contamination control measures can include:
• Removing outer clothing
• Decontamination (wet, dry, or “moist”)
• Dressing patient in contamination control outfit over their clothing
• Wrapping with blankets or sheets.
How far to reach an area with a safe radiation dose rate?
Arriving at the scene of a bombing about 30 min after an explosion was reported
the initial entry identifies a badly injured person at a distance of about 1 m from
a radioactive source. Your radiation detector alarms at a distance of about 30 m
from the source, indicating a dose rate of 10 mGy h
−1 . Using the inverse square
law, dose rate at a distance of 1 m will be higher by a factor of 30
2 , or about
9 Gy h
−1 . At that dose rate, a person will receive a fatal dose of radiation in
less than one hour.
Thirty minutes after the attack, victim has already received a dose of 4.5 Gy
and taking 15 min to stabilize the victim in place is likely to expose them to
a cumulative dose high enough to be potentially fatal, and you will receive a
dose high enough to cause severe radiation sickness. At the same time, their
injuries are potentially severe and you judge that they are unlikely to survive
evacuation to the perimeter (100 m away) without being stabilized. How far
do you need to move them so that they can be stabilized without putting them
at risk from radiation exposure?
If your goal is to keep the total radiation exposure to less than 5 Gy then
they need to be moved to a distance at which they will receive 0.5 Gy in 15 min,
which is a dose rate of 2 Gy h
−1 .
Reducing the dose rate from 9 to 2 Gy h
−1 requires reducing the exposure
rate by a factor of 4.5. Since dose rate drops with the square of distance, the