The methods now permit a greater number of failures per test, reducing the impact of ordinary variability on failure rates. This is a big change that will positively impact companies seeking testing. - Dr. Benjamin Tanner
Round Rock, TX (PRWEB) October 16, 2013
Antimicrobial Test Laboratories (ATL) - a contract microbiology lab founded in 2006 by microbiologist Dr. Benjamin Tanner - has announced that AOAC International’s altered passing criteria for two key methods used for disinfectant registration will benefit companies needing testing in major ways.
According to Dr. Tanner: “AOAC International, a standards-setting organization, recently published changes to test methods used by disinfectant manufacturers to register their products with the United States Environmental Protection Agency (EPA), notably the Use-Dilution Method (UDM) for Pseudomonas aeruginosa and Staphylococcus aureus. The methods now permit a greater number of failures per test, reducing the impact of ordinary variability on failure rates. This is a big change that will positively impact companies seeking testing.”
“This is a great development for industry,” said Jason Williams, Microbiology Manager at Antimicrobial Test Laboratories. “Previously, manufacturers were only allowed one failing test surface per each set of 60 tested. Now, they are allowed up to three failing surfaces for Staph and Six for Pseudomonas.”
“Recent changes to AOAC methods are the direct result of years of hard work by members of industry and employees of EPA, and represent a shining example of industry and regulators working together to improve registration criteria,” noted Dr. Tanner. “Improved performance standards will enable new disinfectants to enter the market while at the same time making efficacy determinations more clear and reliable for EPA.”
One interesting outcome of the change is its effect on test-method-choice by makers of spray disinfectants.
According to Tanner: “Liquid spray products can be tested for registration using either the Use-Dilution Method or the Germicidal Spray Products Method. Historically, spray product manufacturers would choose the Germicidal Spray Products Method, because it had the same pass/fail criteria but demonstrated less variability. Now that the performance standard has been changed for the Use-Dilution Method, we expect most companies to use it for registration instead.”
“Prospective disinfectant registrants should be aware that recent changes to the Use-Dilution Method performance standard come with a catch,” noted Mr. Williams. “Now all three required batches of product must be tested on different days.”
Further, the Use-Dilution method is technique-sensitive, added Tanner: “Despite the new performance standard, companies will benefit from working with laboratories that have conducted the method for years and have well-trained personnel who are experienced with regard to the delicate technique involved in transferring the contaminated surfaces into and out of the disinfectant solutions.”
Experienced laboratories, such as Antimicrobial Test Labs, are familiar with the full range of requirements to ensure successful registration with EPA. For a complimentary needs assessment, visit Use-Dilution Method (UDM) or call 512-310-TEST (8378).