1.1 This test method specifies the operational parameters required to perform a quantitative liquid disinfectant efficacy test against bacterial biofilm.1.2 The test method was optimized and validated for a Pseudomonas aeruginosa or Staphylococcus aureus biofilm grown in the CDC Biofilm Reactor (E3161). The method is suitable for evaluating additional bacteria grown using the procedures outlined in methods with comparable coupon dimensions such as Practice E3161, Test Method E2562, or Test Method E2196.1.3 Disinfectant preparation and contact time are used in the assessment according to the manufacturer’s instructions for use.1.4 The test method uses a closed system to treat biofilm. A coupon is placed in a single tube for the treatment, neutralization, and harvesting steps to prevent the loss of cells.1.5 This test method describes a harvesting and analysis procedure which includes vortexing and sonicating treated and untreated control biofilm, and recovery of culturable cells using