Panasonic PT-DZ12000U Operating Instructions Manual page 82

10CFR20 "STANDARDS FOR PROTECTION AGAINST
RADIATION" and 10CFR835 "OCCUPATIONAL RADIATION
PROTECTION" use the following definitions for ALI and DAC.
10CFR20 Specifies Respiratory Protection Factors while
10CFR835 uses those Respiratory Protection Factors
specified by 29CFR1910 "OCCUPATIONAL SAFETY AND
HEALTH STANDARDS".
Annual limit on intake (ALI) means the derived limit for the
amount of radioactive material taken into the body of an adult
worker by inhalation or ingestion in a year. ALI is the smaller
value of intake of a given radionuclide in a year by the
reference man (ICRP Publication 23) that would result in a
committed effective dose of 5 rems (0.05 sieverts (Sv)) (1 rem
= 0.01 Sv) or a committed equivalent dose of 50 rems (0.5
Sv) to any individual organ or tissue.
Derived air concentration (DAC) means, for the radionuclides
listed in appendix A of this part, the airborne concentration
that equals the ALI divided by the volume of air breathed by
an average worker for a working year of 2000 hours
3
(assuming a breathing volume of 2400 m ).
The following table of Inhalation DAC Factors lists both the
10CFR20 values and the 10CFR835 values for the most
restrictive DAC values in uCi/mL. Due to the somewhat
different work activities in NRC regulated facilities and the
Department of Energy facilities there are some apparent
differences. Also 10CFR835 separates out exposures in
radioactive clouds while 10CFR20 includes those DAC
factors in the main table.
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