A new dynamic performance standard for child restraint systems (FMVSS No. 213) became effective on January 1, 1981. The Office of Vehicle Safety Compliance (OVSC) in the National Highway Traffic Safety Administration (NHTSA) developed a test procedure and conducted compliance tests to determine whether the systems available in the marketplace met the requirements of the standard. The restraints tested were in compliance with the dynamic systems test requirement of the standard, however, some of the systems failed to meet certain component test requirements. Technical investigations were initiated to examine more fully the extent of the apparent noncompliances to the standard.