Vehicle speed relevant

Your editorial (Oct. 24) "Finding natural speed limits" invites comment. It seems to imply that vehicle speed is irrelevant. It seems to be saying that increasing speed limits is responsible for a decline in fatal crashes. Is that really what you meant to say? The "natural" limit, long since concluded by traffic engineers, is the 85th percentile — the point where 85 percent are below and 15 percent are above. This posted limit minimized speed differences among vehicles.

Speed, by itself, of course, does not kill. But "Speed Kills!" has always been a very apt slogan, because excessive speed has always been, by far, the most common contributing factor in serious and fatal crashes.

Much of the reduction in fatalities in 2009 can be attributed to the fact that people have reduced their driving. The dramatic drop in gas prices also bears this out. The main reason for the decline in deaths is that in the 1970s, seat belt use was rare (lots of older cars had none). We had no shoulder belts, no airbags, no hi-tech infant seats, no collapsible steering columns, and cars were not engineered to absorb the impact of front-end collisions as they are now.

Wayne Overson

Santaquin