Peracetic Acid

Peracetic acid (PAA) is produced commercially as a solution in which peracetic acid is in equilibrium with hydrogen peroxide, acetic acid and water.

Commercial solutions contain peracetic acid levels from below 0.1% up to 40%. All peracetic acid solutions are clear, colourless liquids with a pungent vinegar-like odour and the pH of these solutions is less than 1.5.

When handling peracetic acid solutions there are conditions to avoid

Peracetic acid solutions have oxidising and corrosive properties and are organic peroxides.
They are classified as aquatic acute cat 1 above 25% and aquatic chronic cat 3 above 0.025%.

Avoid contamination

Stability is maintained by rigorous care in handling and storage. Although PAA solutions contain a stabilizer, no amount of stabilizer will offset gross contamination. Contamination can cause rapid decomposition, which is highly exothermic and releases large volumes of oxygen which can overpressurise its container and/or equipment, and intensify a fire. Potential contaminants are: heat, metals, incompatible chemicals (alkalis, organic compounds, reducing agents, heavy metals…). Product once drawn from the original container should never be returned due to a risk of contamination and decomposition.

Avoid confinement

Peracetic Acid must not be confined because an inherent property of PAA is the slow release of oxygen over time due to normal decomposition. All commercial containers include ventilation systems to allow release of gas and avoid container distension/bulging. Products must not be confined in containers, vessels, piping systems or between valves. There must always be a pressure release or breathing device.

Avoid personal exposure

Peracetic acid solutions are highly corrosive to skin, eyes and respiratory track. Always use adequate PPE to protect yourself from splashes or mists/aerosols as PAA is highly corrosive. Safety goggles, protective gloves and suitable protective clothing must be worn. If necessary, a gas mask should be used with an appropriate filter. If peracetic acid comes into contact with skin and eyes, it must be rinsed off thoroughly with plenty of water. In any case get medical attention.

Always have water available when handling PAA solutions

When handling PAA solutions, WATER is the key: use it to rinse your eyes and skin in case of direct personal contact, dilute spills with water and use water for fires involving PAA.