The NIJ and the Personal Protective Armor Association (PPAA) agreed on a new standard for body armor in 1987, but since then, 60 percent of the manufacturers' armor have failed the test. NIJ claims the PPAA standard is easier to pass, thereby putting police officers in jeopardy. PPAA officials state that NIJ inconsistently and arbitrarily tests the armor, leaving armor companies frustrated. Du Pont, the manufacturer of Kevlar (the material which makes body armor impervious to attack) has refused to sell to manufacturers who make vests according to NIJ standards because of supposed reliability risks resulting from inconsistent testing. Allegedly inconsistent testing procedures include firing more than the required number of shots and mounting the vests differently. It is also possible that manufacturers have been cheating on the tests by resubmitting rejected items to NIJ's testing arm, the Technology Assessment Program Information Center (TAPIC). PPAA advocates describe the organization's standards as more realistic from the street officer's perspective. Meetings between NIJ, PPAA, and Du Pont representatives have failed to settle the disagreement, despite agreement that officer safety is their priority. NIJ officials admit there is room for compromise within the standards, but at least one PPAA spokesman said his group would not back down from the facts.