Clinical Staff in Proximity of Patient Undergoing a Procedure

For many situations where protective aprons are worn, the exposure is primarily to the front of the individual. Under these circumstances, a personal monitor located under the apron on the trunk of the individual indicates the dose equivalent to the shielded trunk of the body, and unshielded parts of the body may receive higher exposure. A monitor located outside and above the apron indicates the dose equivalent to the unshielded parts of the body. 

For some situations, such as certain nursing procedures, individuals may work part of the time with their backs to the patient while wearing an apron that covers both the front and the back. For irradiation to the back, a personal monitor located on the back under such an apron indicates irradiation of the shielded trunk of the body some unshielded parts of the body may receive higher exposures. A monitor that is located on the front under such an apron is shielded 

Practices differ throughout the United States. Sometimes a single personal monitor is used. Sometimes two personal monitors are used, one under an apron and one outside and above the apron. 

The principal data available to determine or E directly from ifpdO) are conversion coefficients which give the quotient of or E and /fp(lO) [i.e., He/[Hp(10)1 or /[ifp(10)]). The unit for each of the three quantities is Sv therefore, these conversion coefficients are dimensionless. Such conversion coefficients have been derived from calculations for a number of idealized conditions for irradiation by monoenergetic photons of mathematically described reference adult anthropomorphic phantoms. The conversion coefficients are a function of photon energy, photon beam direction, surface of the phantom on which the radiation is incident, and location where //p(lO) is being evaluated on the phantom. 

To use these conversion coefficients directly in practice, one would need to be able to characterize the irradiation conditions in the workplace for a particular situation with regard to the following factors  

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