New York State Department of Health's Wadsworth Center (Certificate Number - 1785.01) is an American Association for Laboratory Accreditation (A2LA) accredited Proficiency Test (PT) provider for the design, preparation, and operation of PT schemes that meet the requirements of ISO/IEC 17043, ISO/IEC 17025, and The NELAC Institute (TNI) Volume 3: General Requirements for Environmental Proficiency Test Providers.

The Environmental Proficiency Testing and Validation Unit (EPTAVU) is a collaborative group of laboratories, within the New York State Department of Health, Wadsworth Center, Division of Environmental Health Sciences, that produce and validate PT samples designed in accordance with the above mentioned standards.  The New York State Environmental Laboratory Approval Program (ELAP) offers the PT samples produced by the EPTAVU program as part of their regulatory program for laboratory accreditation. These PTs are only available to environmental laboratories within ELAP and are not available to the general environmental laboratory community.

PT Studies are conducted for Potable Water Chemistry (36 sample types comprising 158 contaminants), Nonpotable Water Chemistry (38 water sample types comprising 225 contaminants), Water Bacteriology (7 sample types comprising 6 contaminants), Asbestos and Fibers by Light Microscopy (friable bulk materials and fibers in air filters) and Asbestos by Electron Microscopy (Water, Air, and Non-friable organic bound materials).  The full scope by field of accreditation is posted in the ELAP Certification Manual, Item No. 316: Air and Emissions, Microbiology/Bacteriology, Potable (Drinking) Water, Non-Potable Water, Solid Waste and Materials. Each study type is conducted twice per year at six month intervals. The current schedule is posted in the ELAP Certification Manual, Item No. 310.