Viton (Freelander 2)

As with many other automobile manufacturers, some components have O-rings, seals, or gaskets that contain a material known as "Viton".

Viton is a fluoroelastomer, which is a type of synthetic rubber material that contains fluorine. Although the most well-known fluoroelastomer is Viton, there are other similar materials such as Fluorel (Fluorel) and tecmoflone (Tecmoflon).

When used under design conditions, fluoroelastomers are completely harmless and non-hazardous. However, if they are exposed to temperatures exceeding 400°C, the material, although not igniting, will decompose, and one of the decomposition products will be hydrofluoric acid.

This acid is extremely aggressive and can penetrate directly into the body upon contact. IF ON SKIN, SEEK MEDICAL ATTENTION IMMEDIATELY.

O-rings, seals, or gaskets that have been exposed to ultra-high temperatures will appear as charred or as a black sticky mass. Do NOT touch them or any adjacent parts under any circumstances.

To determine whether a particular O-ring, seal or gasket was made of Viton or another fluoroelastomer, inquiries should be made. If the parts were made of natural rubber or nitrile, they are not dangerous. When in doubt, be cautious and assume the worst, i.e. that Viton or another fluoroelastomer was used as the material.

[The original article can be found here LRMAN.ru]

If Viton or any other fluoroelastomer was used, the problem area should be cleaned of contamination before starting work.

Disposable heavy-duty plastic gloves should always be worn. Before removing decomposed Viton residue and final cleaning of the problem area, the area should be washed with wire wool and lime water (calcium hydroxide) solution to neutralize the acid. After use, the above plastic gloves should be properly disposed of.