CPDM Certified Person Sampling Test No. 1 Taken from the CPDM Certified Person Sampling Exam Pool Progress Indicator: Question 1 of 25 1.  A _____________ is permitted to perform cleaning of the CPDM daily, after each use, or as necessary. Choices: person certified in maintenance and calibration for the CPDM mine official person certified in sampling for the CPDM both a. and c.