Deterministic Radiation Effect - Siemens ARCADIS Varic Operator's Manual

Safety
18
of 28

Deterministic radiation effect

As per IEC 60601-1-3, 5.2.4.5 (A.2), deterministic radiation injury is possible if a
radiation dose delivered to an organ or tissue exceeds a value of 1 to 3 grays.
With typical applications and proper use of the C-arm, you do not have to take
such injuries from radiation into consideration. It is assumed that the maximum
fluoroscopic time does not exceed 5 to 15 minutes, depending on the application,
and that the point of skin penetration is 30 cm (50 cm maximum) away from the
image intensifier input.
The skin penetration dose for various operating modes and under standard oper-
ating conditions can be estimated using the "Dosimetric information" table under
the "Technical Information" tab.
Example: An accumulated fluoroscopic time of 15 minutes and a skin penetration
dose of 20 mGy/min yields a dose of 300 mGy.
When changing the distance from the skin penetration point to the focus, please
note that the skin dose decreases with the inverse square of the distance to the
focus. This means that when the distance to the focus is halved, the skin pene-
tration dose rate quadruples.
Operator Manual
SPR2-310.620.30.02.02
0