Tests for allergies includes a skin or blood test to detect the substance that’s causing the allergy. Skins tests are generally preferred as they are reliable, quick, and generally affordable and less expensive as compared to blood tests. The tests on skin can be done on the surface of the skin, under the skin or both ways to check the allergic reaction on the skin and the body .To identify the allergic substance or the cause of allergy the tests must be carried out in a clean environment.