Organic and silicone fluids are designed to be used above their flashpoints. Therefore, if a leak occurs, they pose a greater fire risk than glycols because they are capable of producing flammable vapor concentrations in the area of the leak. Fires involving organic fluids sometimes are caused by catastrophic equipment failure. However, the majority of fires involve improper installation, lack of maintenance on gauges or flow switches, and poor or lacking operating instructions. A flashpoint within the operating temperature range of the system obviously is undesirable as any size leak would create an immediate fire hazard.
Heat is more of a safety issue than toxicity in terms of personal safety.
Fluid running overhead that drips onto an employee can cause an immediate burn. How-ever, it should be noted that thermal burns are not exclusive to heat transfer fluids. Any fluid used at elevated temperatures has the potential to cause a thermal burn if it contacts unprotected skin. The best way to prevent a burn from occurring is to identify small fluid leaks and repair them. Using personal protective equipment such as gloves or long sleeves when repairing leaking equipment or handling fluids also may help prevent a leak from causing a burn.