test your surface

Is it latex or is it oil paint? Here's a simple test to do.

The fastest way to check if the paint is a latex or oil base(alkyd) is to do the alcohol test. Latex paints dissolve in alcohol , a dark rag with rubbing alcohol will show the paint is latex if the rag has some dissolved paint on it. Oil
based paints will only become cleaner . In reverse to determine if a paint is alkyd based repeat this test using
an acetone nail cleaner. It is important to know what you are painting over. Latex over oil/alkyd will peel off , a common mistake made by homeowners worried about lead(pb) levels in old oil paints. The USA stoped lead fillers
in oil base paints back in 1972 ,nearly 40 yrs ago. Nb/ Oil based paints can be applied over latex paints but latex over oil requires a primer.