Met One Sensors Resistant To Vaporous Hydrogen Peroxide (VHP)

Pharmaceutical manufacturers often require an aseptic production environment to minimize the presence of microbes and their potential contamination of the manufactured product. One common method of disinfection is the use of vaporous hydrogen peroxide (VHP). VHP is a strong oxidizer and excellent disinfectant. A typical clean room disinfection cycle consists of a 3% VHP exposure for 45 minutes.

There is a concern that the use of VHP in the presence of optical particle counters can cause damage. When introduced into an air particle counter, VHP could bleach the internal surfaces of the sensor and cause corrosion of the mirror surface, which would increase reflections within the sensor. This in turn, can cause false particle counts.

To better understand the affects of VHP on the sensor in Met One remote air particle counters, Hach Ultra conducted testing on the sensor body, components and mirror.