Is there a default "maximum" value for an acceptable daily exposure (ADE) or permitted daily exposure (PDE) value?
Currently there is no formal regulatory statement or position on the maximum acceptable daily exposure (ADE) or permitted daily exposure (PDE) value.
However, one can draw a conclusion from the OSHA standard for Particles Not Otherwise Regulated (respirable fraction) of 5 mg/m3. If you take the 5 mg/m3 and perform the following calculation:
5 mg/m3 × 10 m3/day (air breathe in a normal work day) = 50 mg/day
Here at Affygility, since we used an adjustment factor of 5 for human variability (worker exposure), we consider a default maximum ADE or PDE as 5 times the OEL.
It should be noted that many pharmaceutical tablets or capsules weigh less than 50 mg, and that 50 mg/day is a high number. It is likely that cGMP requirements for the visually cleanliness of the equipment would come into play before you would reach a 50 mg/day carryover.
It is important to remember that the ADE or PDE is to be used for pharmaceutical manufacturer purposes for cleaning validation, and not as a substitute for inadequate cleaning practices.