High Quality Content by WIKIPEDIA articles! A Precision Measurement Equipment Laboratory (PMEL) is a United States Air Force (USAF) facility in which the calibration and repair of test equipment takes place. This practice is also known as metrology: the science of measurement. The Air Force Specialty Code (AFSC) of airmen trained to work in the PMEL is 2P0X1 replacing 324X0 where "X" represents a variable number which denotes the level of expertise of the individual. There are also defense contractors and government civilians who perform this job.