Zefon PCM & TEM 25mm air sampling cassettes are designed and manufactured to meet all applicable NIOSH, OSHA, and AHERA standards for asbestos air monitoring. The cassette housings are injection molded in-house and are individually assembled and preloaded under stringent quality control standards. Once assembled, each cassette is individually tested prior to packaging for shipment. Random lot sample testing is performed daily by an independent laboratory to ensure low background fiber counts. Laboratory results are available upon request.