Principles of Operation; MSA's own proprietary PID sensor design (patent-pending) provides users with excellent PID performance including humidity resistance, stable zero readings and fast response and clear times. / Approvals & Standards; UL, CSA, ATEX / Applications; Chemical,Clan Labs,Domestic Preparedness,Fire Fighting,Gas Detection,General Industry,Hazardous Materials,Oil and Gas,Spray Painting,Telecommunications,Water/Wastewater / Hazards; Combustible Atmosphere,Confined Space,Oxygen Deficiency,Toxic Atmosphere IDLH,Toxic Atmosphere Non-IDLH / Product Information; Provides users outstanding multifunctional capabilities by integrating a high-performance PID (photoionization detector) sensor into a four-gas detector. Users are able to simultaneously monitor for volatile organic compounds (VOCs) with low vapor pressures while measuring for combustible, toxic and oxygen-deficient atmospheres within one reliable, easy-to-use, durable unit.