hand held dental X-ray devices Flashcards
what is absorbed dose
a physical qunaitiy of Energy absorbed by irraded sample of matter measured in gray
what is equivalent does
A biological effect of radiation type R with weight factor R
how to calculate equivalent does
multiple radition types requireing calculation duing radiation weighting factor then summated
what is the Effective dose
The biological effect on tissue type type T having weight factor wT
Calculation of effecitve dose
Summation of organ doses to those parts irradiated
what is complete (uniform) irradiation
If whole body is irradiated uniformly, the weighting factor becomes one and effective dose = whole body equivalent dose
what is used to convert equivalent dose to effective dose
Tissue weighting facotr
what is used to protect the provider in hand held X-rays
A shield
when is a handheld dexntal X-ray device useful
In missions
what is the key differneces between a handheld and normal X-ray device
Operator holds the handheld so the operator also needs to be protected
Handheld device need a lower output dose rate
what needs to be shielded from the operator
Backscateer radiation
how to stop backscater radiation
instal a backscatter shield at the end of the X-ray tube
what is the minimum for the backscatter shiled
.25mm lead eq
15.2 cm in dimater
no further than 1cm from the end of the PID
can you use a portable X ray device without a backscatter shield
No
problem with backscatter shields
Obstructs the arm of the RINN kit and increase the distance between xray source and patients