The National Institute of Justice (NIJ) has just released, Ballistic Resistance of Personal Body Armor, NIJ Standard-0101.06.  The vests were tested under several different conditions such as, high heat, humidity and mechanical wear prior to the ballistic testing.  You can read more about the Body Armor Safety Initiative and help keep your transportation and other officers safe.  According to the NIJ, "Body armor (which is commonly but inaccurately called a "bulletproof" vest) has saved the lives of more than 3,000 law enforcement officers since 1975."