Personal Environmental Monitor (PEM)

The Personal Environmental Monitor (PEM) is a lightweight, personal sampling device used with a personal sampling pump to provide effective collection of particulates of either 2.5 (PM2.5) or 10 µm (PM10) aerodynamic equivalent diameter in indoor air. Personal exposure is determined through gravimetric analysis for particle mass and chemical analysis for specific compounds. The PEM is available in 3 different flow rates.

• Small and unobtrusive - can be connected to a sample pump and worn in the breathing zone
• Referenced in EPA Method IP-10A
• Suitable for ACGIH thoracic TLVs, including sulphuric acid and cotton dust as thoracic particulate matter with 10 µm PEM

The PEM consists of 3 major parts: cap, impaction ring assembly, and base with after-filter. When used with a personal sampling pump at the required flow rate, the aerosol is accelerated through a number of nozzles in the cap. Through inertia, particles larger than 50% cut-point of the sampler impact onto a greased impaction ring and can be discarded after sampling. Particles smaller than the 50% cut-point pass through the impactor and collect on a 37 mm after-filter.

The PEM was developed for indoor air sampling. While it is not an EPA-certified instrument for ambient PM10 and PM2.5 sampling for the National Ambient Air Quality Standard (NAAQS), outdoor use can be effective if there is no excessive wind velocity or rain present at the time of sampling.