Accelerated Aging is an artificial procedure for establishing the lifespan or shelf life of a product in an expedited manner. Data obtained from the study is based on conditions that simulate the effects of aging on the materials. A product can be released to market based upon successful Accelerated Aging test results that simulates the period claimed for product expiration date (1 year, 2 years, etc). Accelerated Aging data is recognized by regulatory bodies as a conservative estimate of the shelf life, but is only accepted until those tests can be repeated on “real time” aged samples.
The primary accelerated aging standards pertaining to sterile barrier systems for medical devices are:
Accelerated Aging calculation is based on Arrhenius’ equation which simply states that a 10C increase in temperature doubles the rate of chemical reaction. Four variables are used in calculating the accelerated aging test duration. A calculator is provided below to easily explore difference test scenarios.
- Test Temperature (°C)
- Ambient Temperature (°C)
- Q10 (Reaction Rate Factor)
- Real-time equivalent (Days)
- Test Temperature is typically between 50 to 60C, most common 55°C
- Ambient storage temperature is typically between 22°C to 25°C. 22°C results in the shortest test duration.
- Conservative / common Q10 is 2 for medical devices.
- Relative Humidity (RH) is not a factor in the Arrhenius equation. However, RH should be kept under 20% so material is not damaged.
- The expiry date of a medical product is commonly based on its manufacture date. Therefore, some add an extra month to the aging study to allow for sterilization, etc. For example, a 12 month shelf life is simulated based on 13 months.