Safe Handling of Peroxyacetic Acid
Peroxyacetic acid, abbreviated as PAA or POAA, is used by food processors as a post-rinse sanitizer for food contact surfaces. It is also used as an antimicrobial added to process water or applied directly to food products to kill pathogenic bacteria. PAA is a stabilized blend of hydrogen peroxide and acetic acid that is highly effective as a sanitizer or antimicrobial intervention. It is environmentally friendly and rapidly breaks down after use to water, acetic acid (vinegar) and oxygen. As such, it is suitable for use as a sanitizer in facilities that produce USDA organic products.
In its concentrated form, PAA is considered a hazardous material and must be treated with respect; it is both an oxidizer, and corrosive. It causes instant skin and eye burns on contact and may cause fires if the concentrate is allowed to soak into organic materials such as wood, rags or oily material. Despite these concerns it is an effective, economical product that is safe to use when handled properly. PPE or personal protective equipment is essential when handling or dispensing the concentrate. At a minimum, chemical-resistant gloves (Neoprene) and splash-proof eye protection should be worn. Adding a face shield is appropriate if working with larger quantities. Concentrated PAA has a pungent odor (acetic acid) and should only be handled in a well-ventilated area. Prolonged exposure may require the use of a suitable respirator.
PAA decomposes slowly during storage, giving off oxygen, and should be stored in appropriately vented containers. It is also important to use appropriate materials when sourcing dosing or transferring equipment for concentrated PAA. Glass, polyethylene (HDPE/LLDPE) and Teflon (PTFE) are all suitable for handling concentrated solutions. Stainless steel and other polymers should only be used where exposure is short term. Once diluted to the “at use” concentration (usually 100 ppm – 200ppm), most materials except Tygon and rubber are suitable.
PAA products such as Birko’s Birk-Ox™ sanitizer or the Birkoside MP-2™ antimicrobial intervention can be effective tools in your food safety program provided they are handled with appropriate precautions. As with any chemical product make sure that you read and understand the MSDS completely before handling or use.
14 Responses to “Safe Handling of Peroxyacetic Acid”
What type of respirator should be used for prolonged exposure to Paracetic Acid
Tim – thank you for your question. Birko does not make or sell respirators, and as we are not familiar with your facility or how you use PAA, we are not able to make specific recommendations. However the following link does have some general information and a comparison of various respirators that offer protection from PAA vapors.
Is PAA suitable to be used in cleaning draft lines? Thank you!
Great question. Yes PAA is suitable for use on draft lines. We recommend that the lines are cleaned using CELL-R-MASTR or other suitable detergent, rinsed and then sanitized using PAA. Another property of PAA that can be helpful in this situation is its ability to oxidize residual flavors that may have adsorbed onto the draft line material. Running PAA at 350 – 400ppm through lines that have been used for something like Root Beer will in many cases kill any residual Root Beer Aroma or Flavor.
Is PAA will increase the shelf life of the product after disinfection?
Decreasing the total number of bacteria on the surface of a product may extend shelf life, however the primary function of a PAA application is as a pathogen reduction treatment.
At 350 to 500 ppm is 304 stainless steel a good transfer and hold material for PAA?
Yes, 304 Stainless steel is suitable for handling PAA at 350 – 500ppm.
Greetings, I use PAA in my tiny family winery sanitation program:
soda ash soak/scrub/rinse; clear water rinse; PAA rinse. Three questions: 1) what is the shelf life of PAA, stored in its original plastic container, lid just slightly lose to allo for gas escape? 2) what is the easiest way to calculate ppm? 3) what is the correct ppm to use for rinse or spray of winery equipment? Thanks very much!
PAA is inherently unstable and will slowly degrade over time. The rate of decomposition will vary with the storage conditions with both exposure to light and elevated temperatures accelerating the decomposition rate. PAA supplied by Birko will remain above the stated label concentration for a minimum of 6 months from the date of manufacture. The product can be used beyond that point, but it will be necessary to increase the usage rate to achieve a desired concentration. Birk-Ox is supplied at 5.6% (56,000ppm) the ppm can be estimated by multiplying the ppm by the dilution rate, so at a 1/400ppm dilution the solution would be 56,000/400 = 140ppm. Please note that the actual concentration should always be verified using an appropriate test kit. PAA is effective as a sanitizer between 147 and 500ppm. For winery equipment we would recommend 150 – 200ppm.
Could 304 and 316 SS become corroded or damaged in the long run when being soaked 24/7 in a 400-500 ppm solution of PAA? Thank you!
That concentration should not harm the metals.
What is the log kill time for bacteria and yeast using 150ppm BirkOx 5.6% PAA?
Birk-Ox is a sanitizer. Per the label it will deliver a 5 log kill in 60 seconds when used at a concentration between 82 and 500ppm.