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How Good is Your USP <797> Viable Sampling Plan?

Your viable sampling plan can make or break your environmental monitoring (EM) program. Too few sample locations won’t give you the information you need and too many sample locations may risk the act of sampling being a cause of contamination. Hopefully, you have taken on the responsibility of choosing your own sample locations and are not solely relying on your sampling vendor to choose locations for you. It’s an undertaking, but only you know your workflow! More and more inspectors are focusing on where you collect the samples and whether those sample locations are valuable. So, how do you if you have good locations, or if you are even complying with regulations? USP General Chapter <797> provides some guidance on choosing sample locations, but it is very generic. Here is a basic checklist to get you started!

USP Requirement

☐  Every ISO-classified area is sampled

☐  Locations that pose the highest risk to the compounded sterile preparations (CSPs) are sampled

☐  Surface samples are collected on equipment in the primary engineering control (PEC)

☐  Surface samples are collected on staging or work areas near the PEC (Think carts next to PECs!)

☐  Surface samples are collected on frequently touched surfaces (This is a tricky one and will require a risk assessment!)

☐  Surface samples are collected in pass-throughs

Best Practice

☐  ISO Class 5 air and surface samples are collected in the direct compounding area (DCA)

☐  PECs with two DCAs have air and surface samples collected in each DCA

☐  Air samples are collected near PECs, pass-throughs, and in high traffic areas

☐  An air sample is collected in the negative pressure HD buffer room by the door to the anteroom

Sample locations are facility specific and are based on workflow, facility design, and risk to the final CSP. Gather input from different individuals in your organization as you develop the sampling plan. Those that work in the cleanroom suite can provide valuable insight to the best sampling locations. As part of your risk assessment, be sure to document why you chose the sample locations.

Not sure how to go about doing a risk assessment for sample locations? Or want help with creating a sampling plan? Reach out to Pure Microbiology. Remember, best practice makes perfect.

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