ASTM E2274-16. Standard test Method for evaluation of laundry sanitizers and disinfectants.

Test accredited by ENAC (Spanish National Accreditation Entity), for standard microorganisms (bactericidal activity), and through an internal procedure for yeasticidal and/or fungicidal (with Candida albicans and Aspergillus brasiliensis) and virucidal activity (with the viruses of the EN 14476 standard).

This method is designed to evaluate the disinfectants or sanitary products of laundries used in automatic washing processes using volumes of usual wash water, applied to demonstrate the reduction or complete death of a bacterial population in tissues and wash water after a single wash. This method is designed for tests with vegetative bacteria but can be adapted for tests with fungi or viruses. The method simulates the washing conditions, for which a set of tissues inoculated with the microorganisms is placed in a volume of the solution of the evaluated product, in the proportion indicated by the manufacturer, and shaken. After a period of contact time, the washing water, the neutralizing liquid, and the tissue used, are individually grown in a quantitative manner (cleaning efficiency), or qualitatively (disinfecting efficacy). The following bacterial species are used: Klebsiella pneumoniae, Staphylococcus aureus, and Pseudomonas aeruginosa, although other bacteria of choice may be included. The test can be carried out in clean conditions (without organic matter), or in dirty conditions (using some organic matter among the indicated alternatives: defibrinated heat-inactivated bovine serum or a mixture of tryptone, bovine serum albumin and mucin may be used). Six pieces of tissue are used for each microorganism. Three pieces for the test product and 3 pieces for the controls. These inoculated pieces are inserted between the folds of a 15 g piece of cloth and maintained inside the closed exposure chamber under agitation for the time specified by the manufacturer. Once the exposure time has elapsed, the supports and the inoculated pieces of tissue are removed and introduced into a neutralization broth. The filtrate of the neutralization broth, the neutralization broth itself and dilutions prepared therefrom, are cultivated to detect the presence of the inoculated microorganisms, as well as their reduction, if any, expressed in reduction percent. Results are reported as sanitizing efficacy, the mean percentage reduction of microorganisms recovered from the fabric carriers and wash water, and disinfectant efficacy, present if the absence of test microorganisms is demonstrated on the fabric carriers and wash water.

The procedure described by the ASTM E2274 standard has been adapted in our laboratory to evaluate the yeasticidal activity (with Candida albicans), fungicidal (with Candida albicans and Aspergillus brasiliensis) and virucidal activity (with the viruses indicated by the EN 14476 standard) through an internal procedure based on the standard. The BPR:2022 guidance indicates fungi and viruses as test microorganisms and describes the minimum logarithmic reduction to be achieved for bactericidal, yeasticidal and fungicidal activity. If you require the performance of the test under the ASTM E2274 standard, under specific conditions of the BPR Guidance, request the specific information for this test.