United States Pharmacopeia (USP) standards play an important role in keeping staff safe, and facilities in compliance. USP publishes general chapters regarding production and handling of various compounds in order to protect and improve health. We sometimes get questions from labs using OneVue Sense about our compliance with these important standards.
While we encourage our users to whom these chapters apply to read them carefully, there are some general notes I can provide!
USP 795: Nonsterile Preparations
OneVue Sense monitors ambient temperature and humidity via the A100Q service. Whether you’re monitoring personnel wearing the “required garb,” storage spaces, or labs for defining expiration dates, our system measures ambient temperature within 1.0⁰ F between 23⁰ F–122⁰ F (and within 0.5⁰ C between 0⁰ C–50⁰ C). Humidity is accurate to 3% in the 20%–80% relative humidity range.
Given that personal comfort and best practices for storage are within those ranges, our alerts are fully functional to let you know if a space goes out of your specified range for temperature or humidity, so you can intervene accordingly. Sites also have one-click access to historical reports of logged readings to demonstrate compliance.
Naturally, you will want to know your monitoring system remains accurate over time. The CDC Vaccine Storage and Handling Toolkit (v2019, page 10) notes that temperature monitoring devices “can experience ‘drift’ over time, affecting their accuracy” as an explanation as to why “calibration testing should be done every one to two years or according to the manufacturer’s suggested timeline.”
OneVue Sense remains remarkably stable over time. The typical value for the humidity sensing element’s operation in normal RH/T operating range (20%–80%RH) is < 0.25. Maximum values are < 0.5 %RH/yr. Factors driving toward higher drift are environments with vaporized solvents, out-gassing tapes, adhesives, packaging materials, etc.
Assuming our worst-case drift of 0.5% RH/year, it would take 3 years of drift in a consistent direction to be an additional 1.5% out of our stated accuracy performance. Given those conservative estimates, if a sensor element was 3% RH low upon install and continued to drift low at a maximum of 0.5% RH for 3 years, we would still remain accurate to within 4.5% at the end of 3 years. The chances of all those factors happening in one sensor are so low as to negligible. But to avoid any doubt with auditors, sites can subscribe to our NIST program which replaces the sensor unit every 3 years.
Note that if non-preserved aqueous dosage forms are stored in refrigerators, the T101Q service will work. CertiTrak probes show an accuracy within 1.0⁰ F from -40⁰ F to -221⁰ F (and within 0.5⁰ C between -40⁰ C and -105⁰ C).
A Boost to Safety and Compliance
As I have outlined here, our OneVue Sense tools match or exceed the compliance requirements and recommendations spelled out in USP 795. I’ll be writing about how we measure up with other standards soon, so stay tuned!