Category ratings defined. Test instruments are rated on their ability to withstand a voltage spike, which is applied through a specified level of resistance (Table). The ratings are broken down by categories â CAT I, II, III, and IV.
Burning Mouth and Tongue. Burning tongue is an odd sensation in the tongue and mouth that most commonly affects women who are entering or going through menopause. Though researchers are not sure what causes it, several suspects include irritating dentures, nerve damage, or hormonal imbalances.
A yellow coating on the tongue is also caused by inflammation of the papillae, which then collect yellow bacteria. Smoking, mouth breathing, dehydration and fever all cause the papillae to become inflamed.