All you need to know about paint contamination

Simply put, contamination is small particles that get embedded into your vehicles paint work. The most common types of contamination are tar (from the road and tyres), iron (from brake dust and train tracks), bugs and tree sap. Paint contamination will impact the overall appearance of your vehicle as it dulls the finish, makes it look dirty even after washing, and feels rough to the touch.

It is important these contaminants are removed from the paintwork as overtime it will cause the paintwork to deteriorate. It can also cause scratches in the paintwork during the washing stage, or if not properly removed before polishing it will leave circular scratches which are harder to remove.

Side-skirt of a white vehicle with contaminants visible in the paintwork

How do I know if my paint has contamination?

Firstly, the car will need to be washed so there is no confusion between dirt and contaminants. Then, run the back of your hand across a panel. If it is smooth, then you likely do not have contamination in that area. However, if it feels rough or gritty (you may also hear the friction) then it will be worth looking into having a decontamination wash on your vehicle. Depending on the colour of your vehicle, contaminants are also visible (see image above).

How are contaminants removed?

Depending on the level of contamination, and the type of contaminants present, there are different methods that can be done. It is advised to have done thorough research, or to consult people with experience before attempting to remove the contaminants as if it is not done correctly it could create a bigger problem.

Chemical Decon - (do not use chemicals on carbon ceramic brakes)

As you may have gathered, this decontamination is done using chemicals. Starting with a Tar remover which is a solvent based product which will loosen and soften tar spots. Moving onto a fallout remover to remove the iron - have you seen those videos and pictures of the liquid that turns purple? That's what happens at this stage, it reacts to the iron which is what gives it its colour after you leave it to work its magic for a few minutes. You'll notice it will react more on wheels as this is where you will have more iron build up from your own brake dust.

If you are carrying out this process yourself, then please remember to follow the directions on the bottles of your products and wear appropriate PPE.

Contact Decon -

This usually follows a chemical decon but can be done on its own. Contact decontamination is done using a clay bar which is designed to collect any remaining contaminants in the paintwork. Using a clay bar which is specifically for decontamination, spray a section of a panel with soapy water for lubrication and then glide the clay bar from side to side in short but rapid bursts. You can hear the difference between where any remaining contaminants are, and after the clay bar has picked them up and the paint is smooth. When the clay bar appears to be dirty, stretch it out and fold it in on itself a few times to have a clean surface and repeat.

Why is decontamination necessary, and how often should it be done?

Contaminants will build up over time, and as mentioned above, will effect the overall appearance of your vehicle. It will impact the finish of your paintwork so it will no longer be as glossy. 

Frequency will depend on how often your car is used and your driving style. For example, if you travel a lot then you will naturally pick up more tar and iron from the roads, brake dust and also from passing other cars. However, if properly taken care of then you may only need a decontamination once or twice a year. Ceramic coatings, waxes and sealants will also aid in keeping contaminants out of paintwork.

If you are having your vehicle polished, then a decontamination wash is vital before any polishing can begin. This is because any contaminants in the paint will transfer and get embedded in the polishing pad which will lead to scratches and further complications.

Concerned about contamination in your paintwork? Get in touch and we will discuss which of our services best suits your needs!