If the NFL wants to assure safer playing conditions, it needs to require immediate changes to the turf at some stadiums and make other modifications, players association president JC Tretter said.
Tretter, in a post on the NFLPA's website on Saturday, called on the league to ban the slit film playing surface, saying it has led to "statistically higher in-game injury rates" compared to all other surfaces for non-contact injuries and injuries to the lower extremities, such as ankles and feet.
Seven teams currently play home games in stadiums with slit film turf, according to Tretter: New York Jets and Giants (shared stadium), Detroit Lions, Minnesota Vikings, New Orleans Saints, Indianapolis Colts and Cincinnati Bengals.