Paint thinner is used to thin oil-based paint and also to clean excess paint from work surfaces or application tools. There are many different types of paint thinner available, all of which have varying degrees of toxicity. On the whole, most paint thinners are dangerously toxic if not used and disposed of in the right manner.
Tip: If you have multiple cans of a custom-blended paint, and you can tell right away that they need to have paint thinner added because the paint is too 'heavy or thick, you have to use an empty can and pour all of the different cans of paint back and forth into each other for a uniform color. This would be the time to blend in a small amount of paint thinner as well to rid the paint of that thickness. Custom colors may vary slightly from can to can; this is why pros pour them back and forth between cans. This is called 'boxing' the paint.
Work in a Well-ventilated Environment
Paint thinners emit toxic fumes, which can cause nausea, headache, or breathing trouble, among several other immediate and long-term health problems. When you work with paint thinners, you must ensure adequate ventilation in the work area. Leave windows or doors open for proper air circulation. If this is not possible, make use of exhaust fans.
Wear Safety Equipment
Wear safety goggles and a respirator when you are working with paint thinners. These articles will protect you from possible splashes or fumes.
Take Prompt Steps for Required First Aid
If you or a helper experiences breathing trouble, skin irritation, or has accidental contact with thinner on their eyes or other sensitive organs, arrange for immediate medical attention. Wash paint thinner off of skin with water and soap. If paint thinner is splashed into the eyes, you should flush it away with running water for 10 or 15 minutes, and then seek medical attention.
If paint thinner is ingested, contact your local poison control center and arrange for medical aid.
Keep Paint Thinner Away From Acidic Materials
A paint thinner can react with acids and acidic materials in a hazardous chemical reaction. You must keep the two separate at all times.
Avoid Mixing Paint Thinner With Substances Other Than Paint
Never mix paint thinner with other substances, whether solid or liquid. It may result in explosive chemical reactions.
Keep Away From Combustible Materials and Heat
Paint thinner is a volatile substance that must be kept away from combustible materials, liquids, heaters, and open flames.
Never Consume Food in the Vicinity
Never eat or drink in the work area when you are handling paint thinners. The food substances can easily be contaminated and you may unknowingly ingest paint thinner.
If you have paint thinner or oil-based paint on your hands, and you want to eat between tasks, leave the room and wear latex or nitrile gloves on your hands while you eat.
Never Use Paint Thinner as a Generic Cleaner
Never use paint thinner to clean countertops, floors, or walls. In addition to the risk of fire, you will be exposed to the fumes indoors for extended periods of time. In addition, paint thinner can be very harmful to certain surfaces and adhesives or painter's caulk.
Wash Your Hands After Use
After using paint thinner, you must wash your hands thoroughly with soap and water. This will keep your skin clear of the thinner, reduce chances of skin inflammation or irritation, and reduce the chances of contamination of foods and drinks.
Never Smoke in the Vicinity
This may seem like a given when we consider the dangers of keeping thinner near heat, but smoking in the presence of paint thinners is very dangerous. If an open flame lands on the thinner, it could result in uncontrollable flames.
Dispose of Unused Paint Thinner Properly
Paint thinner is a hazardous waste, which must be disposed of according to the rules and regulations set for its use. Never throw paint thinner in regular trash or pour it down drains.
Tip: Some people have been known to have good luck with having service stations or oil change establishments taking used paint thinner for disposal. They have big underground tanks and any petroleum product including, paint thinner, is recycled into good motor oil. A paint thinner can often be re-used. If allowed to sit for long enough, the thinner that was used to clean brushes will decant, and all of the paint material will settle to the bottom inch of the container, with usable paint thinner on top of it.
Keep Containers Tightly Closed and Safely Stored
Keep paint thinner containers tightly closed to prevent spillage, and store it in a cool, dry, safe place that is inaccessible to unauthorized people.
Rags that have been soaked or used with paint thinner are very flammable, and spontaneous combustion can often occur if the right conditions come about. The safest way to dispose of thinner-soiled rags is to put them underwater. Use a container full of water, put the rags in, put the top on, and no fire can start.