There are any number of scenarios under which FSIS may decide to perform its own environmental sampling in a slaughter or processing facility.

Environmental sampling will necessarily be more frequent if your company processes ready-to-eat (RTE) products for distribution into commerce. Alternatively, even if your company does not process RTE products, FSIS might demand environmental sampling in the unfortunate event the agency ever suspects that your company might be linked to an emerging foodborne illness outbreak.

Regardless of the scenario, a company is always welcome, when FSIS performs environmental sampling, to take its own “sister” or “companion” sample for its own testing. There are, however, diverging opinions regarding whether companies should take their own samples when the inspectors come knocking.

Those who encourage the practice generally argue that a positive agency test result can be more effectively “challenged” if the company’s own companion samples test negative, I’m not sure, however, that I personally buy this logic. Namely, this is because in the event an FSIS sample tests positive, the agency will typically not care about the results of the company’s own testing. Moreover, they will declare, contamination is not distributed evenly and testing sensitivities vary.

Thus, regardless of whether or not companion samples are taken, FSIS will in virtually all instances treat its own positive result as a “positive finding.” Depending upon the underlying circumstances and reasons for collecting the sample, the agency will then take whatever action it deems necessary based solely upon their own result.

I have also witnessed the awkward situation in which the agency conducts its own testing, the results of which are all 100% negative, and the company’s own companion samples test positive. Oops.

This can create more complex challenges when food product contact surfaces (or even food products) are involved. As shown by these circumstances, too, a company may be better off stepping aside and simply letting the agency do its testing.

Nevertheless, if you insist on taking companion samples when FSIS tests, I would encourage you to adopt a written policy governing the circumstances under which those samples will be taken.

In my view, such a policy should define the circumstances under which companion samples will be collected, and then also state that the samples will only be tested in the event of a FSIS positive. The policy should also articulate the justification for the companion sampling, and make clear that if the FSIS sample tests negative, any companion samples will be discarded within a set period of time (i.e., 24 hours).

If a company adopts and closely follows such a policy, it should be able to avoid any second-guessing from the agency (or a trial lawyer) if a subsequent issue arises or a recall later occurs. This way, you can still test the tester, but not test your luck.