Wayne State University, Department of Neurosurgery, was contracted in 1971 by NOCSAE to develop voluntary standards for football helmets. Preliminary tests of representative football helmets on cadavers and the Z-90 metal head form showed that a more realistic head model was necessary before it was possible to understand helmet performance. A synthetic model was developed which approached human cadaver performance and at the same time was more rugged and repeatable than a cadaver head. A test method was devised and a human tolerance limit of 1500 Severity Index based on resultant CG head accelerations was adopted as the performance standard. All new football helmets available for use in high school and college football have now been certified by the NOCSAE standard and the wearing of such helmets is mandatory for college players in 1978 and high schools in 1980. By means of design or material changes, certified helmets on the NOCSAE tests are performing at a Severity Index of 1/2 those posted by prestandard models, on the average. Experience with the equipment at a helmet reconditiong plant shows that 25% of precertified helmets being received are rejected and 84% of the remainder are testing on the front location (most critical) above a Severity Index of 1450, and should be replaced as soon as possible with certified helmets.