OSHA Ionizing Radiation Standard

[steve.epperson@srs.gov]

     Greetings,
     
     I recently came across the OSHA Standard 29 CFR 1910.1096 (previously 
     1910.96?), "Ionizing Radiation", and have some questions on it.  In 
     particular, section 1910.1096(c)(1) states that the DAC values in 10 
     CFR 20 are "for exposure to the concentrations specified for 40 hours 
     in any workweek of 7 consecutive days."  The standard goes on to state 
     that for exposures less than 40 hours the limits can be increased 
     proportionately and decreased proportionately if exposures are greater 
     than 40 hours.  I am trying to find out the basis for these 
     statements.  I would appreciate anyone knowledgeable on this standard 
     to call or write me back.
     
     Thanks
     
     Steve Epperson
     Westinghouse Savannah River Co.
     (803) 725-2193
     steve.epperson@srs.gov