Is there guidance regarding the method to use for swab sampling?
Yes, as written in section 4.2 of the MFHPB-30 method from the Compendium of Analytical method, the analyst should follow the environmental sampling procedures given in MFLP-41A and B. The website address for the Compendium of Analytical method is: http://www.hc-sc.gc.ca/fn-an/res-rech/analy-meth/microbio/index-eng.