Qualitative fit testing is conducted by putting a hood over the test subject who is wearing the mask being tested. Bittrex or Saccharin are sprayed into the hood and the mask’s fit factor is decided if the test subject can smell or taste anything. If the mask fits properly, all seams should be leak-proof which means the subject should not be able to smell or taste the spray. While this test can be subjective to each person’s specific senses, qualitative testing can be used if the individuals are not in direct contact with any exposure. The individual wearing the respirator must remove any facial hair that lies where the seal has contact with the face.