UN 1089 — Acetaldehyde

Acetaldehyde is a chemical compound used as a solvent, intermediate, and raw material in the production of various chemicals. It is classified as a DOT class 3 hazardous material. Acetaldehyde is widely used in the chemical industry and is transported in large quantities. First responders may encounter acetaldehyde during chemical plant accidents, transportation accidents, or other industrial incidents. The scale of production and transport of acetaldehyde is significant, with thousands of units being manufactured and shipped every year. Acetaldehyde is a highly flammable substance that can cause severe burns and respiratory problems. It is essential for first responders to be aware of the hazards associated with acetaldehyde and take necessary precautions when handling it.

Hazard overview: Acetaldehyde is a highly flammable substance with a flash point of -38C. Vapors may travel considerable distance to an ignition source, and the substance may polymerize in the presence of acids, bases, or heat. Acetaldehyde is toxic by inhalation, with an OSHA PEL of 200 ppm. The vapor density of acetaldehyde is 1.5, which can lead to the accumulation of the gas in low-lying areas. The boiling point of acetaldehyde is 20.2C, and the substance is not reactive with water. The worst-case scenario for first responders is a large spill or fire involvement, which can lead to a significant release of the substance and put people at risk.

Response guidance: In the event of an acetaldehyde spill, it is essential to isolate the area immediately. The ERG 129P recommends isolating the spill area 50m in all directions. For large spills, the isolation distance should be increased to 300m downwind. The correct suppression agent for acetaldehyde is not specified, but it is recommended to eliminate ignition sources immediately. Decontamination is crucial, and CHEMTREC should be contacted in case of an emergency. First responders should be aware of the potential for acetaldehyde to spread quickly and take necessary precautions to prevent exposure.

Firefighter training notes: First responders should be trained to handle acetaldehyde spills and leaks. A critical competency requirement is the ability to identify the substance and take necessary precautions to prevent exposure. A known tactical error for this chemical class is underestimating the potential for acetaldehyde to spread quickly and failing to isolate the area properly. ICS position needs and mutual aid criteria should be established to ensure a coordinated response to acetaldehyde incidents.

Regulatory context: Acetaldehyde is classified as a DOT class 3 hazardous material. The OSHA PEL for acetaldehyde is 200 ppm, and the substance is listed on the CERCLA list. Acetaldehyde is regulated by the EPA as a hazardous substance.

Storage & handling: Acetaldehyde should be stored in a well-ventilated area, away from incompatible materials such as strong acids and bases. The temperature limit for storage is typically between 15-30C, and the container type should be compatible with the substance. The top 3 incompatible materials for acetaldehyde are strong acids, strong bases, and heat sources.