USP 797
USP 797
Agape Instruments Service, Inc. does provide USP 797 “Environmental Viable Airborne Particle Testing” or in laymen’s terms, Airborne Microbial Sampling.
The following description of our sampling procedure should answer several general questions you may have about our viable testing.
Agape Instruments Services, Inc. procedure for microbial sampling is as follows.
Isolators – We do 1 location in the pass thru and 1 location in the main chamber. An Isolator has two different environments separated by a pass thru door and therefore require sampling in each environment.
Biological Safety Cabinets – We do 1 location in the center of the work surface.
Laminar Flow Clean Bench – We do 1 location in the center of the work surface.
For every location, we do one sample with MEA for Fungi and one sample with TSA for Bacteria. We collect 1000 liters of air using an impaction sampler as described in USP-797 so that we can use Table 2 (Recommended Action Levels for Microbial Contamination).
USP 797 states: ” Selected sampling sites shall include locations within each ISO Class 5 (see Table 1) environment and in the ISO Class 7 and 8 (see Table 1) areas and in the segregated compounding areas at greatest risk of contamination (e.g., work areas near the ISO Class 5 [see Table 1] environment, counters near doors, pass-through boxes). This quote is from the section Sampling Plan. There is another statement that can be found under Viable Air Sampling that says ” For low-risk level CSP’s with 12-hour or less BUD prepared in a PEC (LAFW’s BSC’s, CAI’s) that maintains an ISO Class 5 (see Table 1), air sampling shall be performed at locations inside the ISO Class 5 (see Table 1) environment and other areas that are in close proximity to the ISO Class 5 (see Table 1) environment during the certification of the PEC.” These two statements direct us to perform Viable Air Sampling in the room regardless of whether or not an Isolator, BSC, or LAFW is being used for the ISO Class 5 environment.
USP-797 does not give any specific number of samples or a formula to calculate the number of samples for either the PEC or the room. USP-797 only states, “An appropriate environmental sampling plan shall be developed for airborne viables particles based on a risk assessment of compounding activities performed.” The counter would most likely be a good place to perform a sample for the room. The way that we determine the number of samples for a room is by using the calculation in ISO 14644, which is, the standard used for performing Non-Viable Particulate Sampling. Our logic is that if USP-797 wont give us a formula to calculate the number of viable samples then we will use the formula that is listed is ISO 14644-1. We figure if this formula gives us a good sampling plan for non-viables then why wouldn’t the same formula work for viables? The only difference is the fact that the non-viable sampling (particle counts) does not detect what the particle is but only counts it and the viable sampling uses growth media to determine if the particle is a living organism. The formula listed in ISO 14644 is the square root of the room area in square meter. Most pharmacy rooms have between 3 and 5 locations when using this formula.
Most of our customers rely on us to develop a sampling plan for them, so we came up with what we believe is a robust program that will fit the needs of most of our customers. Some customers are fine with our program and some want to take it a little farther. We have some customers that have us do not only the airborne samples but also the surface samples and the gloved fingertip samples. If you would like to develop your own personal sampling plan based on your facility design, we would be more than happy to perform the sample collections for you. If you chose to develop your own sampling plan then you would just need to give us the plan particulars so that we can adjust the pricing and determine the number and type of sampling plates necessary to complete the work.
