« Back to Dictionary Index

Toxic Coolant:

Toxic coolant refers to transfer fluids with a Gosselin rating of two (2) or more, as classified by the BOCA Basic/National Plumbing Code. These fluids are considered essentially toxic and can pose risks to human health and the environment.


  • Transfer Fluids: Fluids used in various systems for transferring heat, such as cooling systems in automotive engines, air conditioning systems, and industrial processes.
  • Gosselin Rating: A rating system used to classify the toxicity of fluids, with a rating of two (2) or more indicating significant toxicity.
  • BOCA Basic/National Plumbing Code: Regulatory standards that govern plumbing practices, including the handling and disposal of hazardous fluids.

Examples of Toxic Coolants:

Ethylene Glycol:

  • Commonly used in automotive antifreeze and coolant formulations.
  • Highly toxic if ingested, causing severe health issues or even death.

Hydrocarbon Oils:

  • Petroleum-based oils used in hydraulic systems, lubrication, and heat transfer applications.
  • Can pose health risks if inhaled or absorbed through the skin, and may be environmentally hazardous if leaked or spilled.

Ammonia Refrigerants:

  • Used in refrigeration and air conditioning systems for their cooling properties.
  • Inhalation of ammonia vapors can cause respiratory irritation and other health problems.


  • A highly toxic and reactive compound used in various industrial processes, including as a rocket propellant and in boiler water treatment.
  • Exposure to hydrazine can cause severe burns, respiratory issues, and neurological damage.

Risks and Regulations:

  • Human Health: Exposure to toxic coolants can result in serious health effects, including respiratory problems, skin irritation, organ damage, and in severe cases, death.
  • Environmental Impact: Improper handling or disposal of toxic coolants can lead to contamination of soil, water, and air, posing risks to ecosystems and wildlife.
  • Regulatory Compliance: Regulations such as the BOCA Basic/National Plumbing Code govern the safe handling, storage, and disposal of toxic fluids to minimize risks to human health and the environment.

Safety Measures:

  • Personal Protective Equipment (PPE): Use appropriate PPE such as gloves, goggles, and respiratory protection when handling toxic coolants.
  • Safe Handling Procedures: Follow established protocols for the safe storage, transfer, and disposal of toxic fluids to minimize exposure risks.
  • Spill Response: Have procedures in place to respond quickly and effectively to spills or leaks to prevent environmental contamination and minimize exposure risks.


Toxic coolant refers to fluids with significant toxicity, as classified by regulatory standards such as the BOCA Basic/National Plumbing Code. Examples include ethylene glycol, hydrocarbon oils, ammonia refrigerants, and hydrazine, which can pose serious risks to human health and the environment if not handled properly. Compliance with safety regulations and proper handling procedures is essential to mitigate risks associated with toxic coolants.

« Back to Dictionary Index