O C T O B E R 2 0 1 5 O U T P A T I E N TS U R G E R Y. N E T 7 1
cal devices should have their exposure lev-
els monitored.
But a commonly asked question is
whether personnel in sterile attire need to
leave the room when radiation-emitting
devices are being used. The answer is no.
Typically they need only be about 6 feet
away from the source, or a little farther if
the source isn't angled straight up and
down.
The collective evidence, taken from
more than 20 sources, establishes that the
radiation dose received by personnel
decreases dramatically as the distance
from the source increases. That's due to a principle known as the inverse square
law, which states that, for example, when the distance between the person and
the source is doubled, the exposure is decreased by a factor of 4 (2 squared)
and when the distance is tripled, the dose is decreased by a factor of 9 (3
squared).
Six feet is considered the distance at which exposure is decreased to a safe
level (but many state and local regulations require all personnel in the room to
use some form of shielding). The bottom line: Personnel should always stay as
far away as possible from the radiation source and limit the amount of time they
spend close to it, but there's no need to leave the room and increase risks of
outside sources contaminating the OR. If someone must leave during a proce-
dure, rolling lead doors provide excellent protection and decrease the likelihood
that the sterile field will be contaminated.
z EQUAL PROTECTION Lead
aprons have long been the stan-
dard, but lighter aprons made from
tungsten-antimony and bismuth-
antimony are just as effective.
