Stability Testing for Temperature and Humidity
Stability testing is a critical part of drug and medicinal product development to determine the shelf life of such products under a variety of environmental conditions such as temperature and humidity. Family prescriptions likely have on their label a recommended “use by” date and notification if special storage conditions should be observed. The regulatory mandate for stability testing in the United States is contained in 21 CFR Part 211 Section 166.
Tests to determine storage requirements and shelf life for drugs and other medicinal products are taken under a variety of imposed and tightly controlled environmental conditions. Because testing time can be extensive accelerated studies are permitted to support tentative expiration dates provided full shelf life studies are being conducted.
Temperature and Humidity Test Chamber Specs
Stability testing is performed in specially designed test chambers capable of duplicating a broad range of temperature and humidity levels replicating environmental conditions where the products under test are to be used. Examples of these chambers are Nor-Lake Scientific chambers available from Tovatech in storage capacities of 24, 33, 52 and 80 cubic feet. We present here selected characteristics of these units that can assist you in specifying chambers for your requirements.
- Temperature: Fully programmable logic microprocessor control (PLC) systems constrict temperature variation to ±0.5⁰C over an operating range of 4⁰ to 70⁰C (solid door models) or 20⁰ to 60⁰C on glass door models. Internal temperature and other data are continually displayed on the 4×20 character LCD.
- Temperature Uniformity: Over the operating range temperature uniformity within the test chamber is ±1⁰C determined by 9 thermocouples on 3 strategically placed horizontal planes.
- Humidity Variation: Over a temperature range of 5⁰ to 60⁰C the set humidity remains within ±5% of the specified level. Humidity is provided by a centrifugal atomizer; dehumidification is accomplished with a separate latent coil. Both are controlled by the programmable microprocessor.
Internal environment is managed through a ceiling plenum that delivers conditioned air evenly throughout the test chamber. This system quickly reacts to remove heat introduced with door openings or changes in product load.
Stability Testing Chamber Monitoring
Temperature fluctuations within stability testing chambers can occur and must be announced immediately. The Norlake units have several alarming functions including audible and visual hi/lo temperature alarms plus remote alarm contacts to alert personnel in other areas of the facility. Alarms area activated if the door is left ajar or a power or sensor failure.
Other monitoring functions include door locks and password protection to control access, and 100-event alarm logging with date and time. Optional features include a temperature time recorder or a digital data logger that can be detached from a temperature probe allowing data to be transferred to a PC or Mac using a USB flash drive.
For additional information on stability testing check 21 CFR Part 211 Section 166. Then call the scientists at Tovatech for assistance in selecting the right chamber for your requirements.