This test is considered to be the most conclusive, non-spermatozoa test for the presence of semen.
The content of this enzyme is from 20 to 400 times greater in human semen than in any other fluid. This fact makes it unlikely that another material would test positive and give false results. The reagents for determining the presence of acid phosphatase in suspected stains are sealed in glass ampoules to ensure their integrity and long life.
Preliminary examination before testing should be accomplished with longwave ultraviolet lights or an alternate light source such as BLUEMAXX™. The reagents should not be applied directly to suspected stains, thus eliminating the possible contamination in subsequent laboratory tests of the recovered evidence. The “contact” method, i.e., wetted filter paper is touched to the suspect area and the reagent is then applied to the contact paper only.