What is Peracetic Acid (PAA)?

Peracetic Acid (PAA) is a highly corrosive chemical used in hospital endoscopy, sterilization, poultry & meat processing, food processing, and many other industries. On this page we will cover the chemical properties, microbial activity, applications for use and hazards & risks. If you are strictly looking for the regulations that have been set for Peracetic Acid or the monitoring solutions that we offer to protect employees from over-exposure to PAA, visit one of those other pages. Skip to find exactly what you're looking for with one of our quick links below:

Monitoring Your Environment &

Understanding Peracetic Acid

Peracetic Acid, also known as peroxyacetic acid or PAA, is an organic chemical compound that is used in a mixture with acetic acid and hydrogen peroxide in water. It is a colorless liquid that has a strong vinegar like odor that can be smelt at very low levels. It is a strong oxidant and is highly reactive. However, it breaks down to acetic acid (vinegar) and water leaving no harmful residue, which makes it the chemical of choice when looking for a food-safe antimicrobial.

Peracetic Acid is produced by combining hydrogen peroxide, acetic acid and water. PAA functions as a disinfectant by oxidizing the outer cell membrane of microbes. The more concentrated the Peracetic acid solution, the more effective it is as an antimicrobial, but the greater the vapor concentration and so the greater the exposure risk to everyone around. This highly biocidial oxidizer shows good efficacy against a broad spectrum of pathogens.

Microbial Activity: PAA will inactivate  gram-positive and  gram-negative bacteria, fungi, and yeasts in <5  minutes at <100 ppm. In the presence of organic matter, 200-500 ppm  is required. For viruses, the dosage range is wide (12 -2250 ppm), with poliovirus inactivated in yeast extract in 15 minutes with 1500 to 2250 ppm. Bacterial spores in suspension are inactivated in 15 seconds to 30 minutes with 500 to 10,000 ppm (0.05 to 1%).


Peracetic Acid is a highly corrosive chemical.

Common Applications for Peracetic Acid

The main chemical used in protein processing is Peracetic Acid

Proteins Processing

Peracetic Acid (PAA) is the predominant antimicrobial chemical used in poultry and meat processing. It is delivered in large totes, diluted and distributed to various areas of the processing plant as an intervention to meet USDA food safety guidelines. Learn more about industry regulations on our Regulations page.

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Peracetic Acid is the chemical of choice in endoscopy cleaning

Endoscopy/ Sterilization

The use of sterilants and High Level Disinfectants (HLDs) such as Peracetic Acid present a risk to those people performing these essential tasks. Gas vapor monitoring for equipment leaks or exposure due to work practices is an essential part of the means to ensure that these chemicals can be used safely.

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Food processing and produce use peracetic acid to sterilize their products

Food Processing and Produce Disinfection

In addition to being effective against bacteria, any biocidal chemical that will be applied directly to food must not leave any harmful residues. Peracetic acid is very reactive and quickly decomposes to acetic acid (acid in vinegar), oxygen and water. 

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Aseptic packaging uses peracetic acid to sanitize their bottles

Aseptic Packaging

Peracetic Acid or Hydrogen Peroxide is the biocide of choice when it comes to Aseptic Packaging. These chemicals help to extend the shelf-life of low acid bottled products. Peracetic Acid does come with significant health risks, so it is important to take the necessary precautions to keep employees safe.

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Interested in monitoring for Peracetic Acid for your application?

PAA Application

What are the dangers of Peracetic Acid

Peracetic Acid safety is a major concern for anyone potentially exposed because PAA is corrosive to the eyes, the skin and the respiratory tract.  Exposure to peracetic acid can occur from inhalation and / or direct contact with the liquid or aerosol. According to NIOSH, symptoms of acute exposure to peracetic acid vapor include cough, labored breathing, and shortness of breath; skin redness, pain, and blisters; severe deep burns to the eyes.  Concentrations of 15% or higher, also give rise to fire and explosion hazards and reactivity issues. It is important to ensure that training for use and safety precautions for peracetic acid are in place.

Another major concern is that peracetic acid has a vinegar type odor, even at low levels, so the challenge becomes knowing if your level of exposure is safe... whether you smell it or not.  If you are working around PAA and over time you do not smell it, it may be due to olfactory fatigue. Olfactory fatigue is also known as nose blindness or odor fatigue. In summary, your sense of smell is an unreliable means of protecting yourself from over-exposure to PAA. So, while making sure the items you're disinfecting are safe for others, be sure to keep track of peracetic acid exposure levels for your own safety and others in the work environment. 

  • Eye irritation : eye damage after prolonged exposure

  • Respiratory distress: fluid in the lungs after high level 
    of exposure (edema)

  • Nose and throat irritation

  • Asthma associated with workplace exposures

  • Skin irritation dermatitis

  • Data on animals showed: hemorrhage, edema, and pulmonary consolidation

Chemical burn to hand due to direct contact to peracetic acid

Overexposure to peracetic acid vapor can cause serious eye irritation

Overexposure to peracetic acid vapor can cause nose irritation and bleeding

Overexposure to peracetic acid vapor can cause lung complications

Is your work environment Safe? How do you know? 

Contact a ChemDAQ technical sales representative today.