The top U.S. vehicle safety regulator said on Wednesday the government needs to be more nimble in designing rules for self-driving vehicles. The industry "is on version 238.32 by the time we get regulations out," National Highway Traffic Safety Administration (NHTSA) administrator Mark Rosekind said during an appearance at an industry conference in suburban Detroit. U.S. Department of Transportation guidelines expected in July will offer different approaches to oversight of self-driving, or autonomous, vehicle technologies, Rosekind said. Regulations that remain static for years "will not work for this area," Rosekind said. "We will have something different in July."