Specifically the ANALITE NEP9000 non-wiping probes are designed for applications where bio-fouling will not build up to obscure the optics such as in short monitoring deployment or placement in fast and cold running water. The ANALITE NEP9500 probes however, with their integral wiper assembly, are designed for operation where bio-fouling or sedimentation buildup is likely. The standard ANALITE NEP9000 and NEP9500 series of probes with its acetal housing may be submerged to a depth of 50 meters (165 feet). An optional stainless steel housing is available for applications where a greater depth rating is required but not recommended for deployment in salty or acidic water where crevice corrosion may occur. Its depth rating is 100 meters (330 feet).

The ANALITE NEP9000 and NEP9500 probes use 90° optics and employs infrared light in accordance with ISO7027. All probes use a unique modulation technique that ensures almost total rejection of ambient light conditions as well as a unique microprocessor controlled differential sample and hold circuit for enhanced performance particularly at low turbidity levels.