An Insurance Institute for Highway Safety study summarized in the September 8, 2010, issue of Status Report shows that usage of tethers for forward-facing child restraints has not increased in recent years. The report, based on observations made this summer of more than 1,500 child restraints, found a 43 percent overall tether usage rate. When looking only at the vehicles made in 2001 and after, when factory-installed tether anchors were required, 47 percent of tethers were used, but even this higher number dropped by 4 percent when counting only those that were tightly adjusted. The researchers stressed the need for more attention to tethers in public education, whether CRs are being installed with lower anchors or with seat belts.
To gather data, CPSTs visited parking lots in the metropolitan Washington, D.C., area, looking into vehicles with forward-facing CRs installed and noting vehicle information, the seating position used, and the presence of a tether. They also looked at tether strap tightness and how the tether was routed in relation to the head restraint, if there was one.
Tether use, not surprisingly, was far less likely in older vehicles. In 2001 and newer vehicles, the observers found a 47 percent usage rate, but in older vehicles the rate was only 19 percent. In sedans, SUVs, and minivans, the usage rates were almost the same (ranging from 43 to 45 percent), but in pickups (a very small group in this sample), the rate was only 17 percent.
Over 95 percent of the CRs were installed in the second row, with 2.9 percent in the third row. Most were in an outboard position, with only 14.8 percent in the center. Some tethers (4 percent) were attached to vehicle hardware not designated as a tether anchor. Nearly all tethers were correctly tightened, and were more likely to be taut when they were positioned under a head restraint rather than over or around it (though vehicle manufacturer’s instructions must be followed for proper routing, and sometimes routing over or around is specified).
The article cites two earlier studies of tether use to make comparisons. In 2003, when tethers straps and anchors were relatively new equipment, the IIHS published an observational study that found a 47 percent usage rate. A seven-state NHTSA study in 2005 found 55 percent tether use.
The population in areas in which the 2010 survey was done is fairly affluent and well educated. Therefore, the researchers caution that the current study may actually overestimate usage in areas with less-affluent, less-educated families.
Noting that observations of lower LATCH anchor use (2005 NHTSA study) show that many people continue to use the seat belt instead of lower anchors to install CRs, the researchers suggest that tether use be emphasized when teaching parents about installing CRs with seat belts. Tethers are equally beneficial when used with a seat belt or with the LATCH system.
Reference: Jermakian, JS, and Wells, JK. “Observed Use of Tethers in Forward-Facing Child Restraint Systems.” Summarized in Insurance Institute for Highway Safety Status Report. 8 September 2010. 45(9). www.iihs.org.
© Safe Ride News September/October, 2010