General Motors gave away three new cars to employees at its large Technical Center here over the past year or so. And GM, of course, doesn't usually give cars away. The automobiles were rewards given employees at the tech center for wearing their seat belts, part of a safety research project.
Goal of the program was to determine what had to be done to persuade employees of the vast GM Technical Center just north of Detroit to increase their use of seat belts - the employees becoming the research subjects.
The program was run on a relatively low level within GM as part of an effort to support the National Highway Traffic Safety Administration's national program to increase belt usage.
There are some 6,000 workers at the GM tech center, about three-fourths white collar and the remainder hourly wage earners. Before the program began, belt usage by employees was already high at 36 percent, about double the percentage of drivers who wear belts nationwide.
All employees were issued preprinted computer pledge cards to sign saying they would wear belts for a year both at work and away. They were told only those signing would be eligible to win the car or other prizes, and usage would be randomly monitored.
The task group that set up the program monitored belt usage at one of the five tech center gates on a rotating basis.
Response to the first phase over a one-month period was huge. More than 80 percent of the workers signed pledge cards. Belt usage jumped immediately to 50 percent and averaged more than 60 percent for the test month.
A second phase soon afterward aimed at raising belt usage to 65 percent. The prize was upped from a subcompact to a compact car, and the winner ultimately picked a Cadillac Cimmaron. This test period ran for six weeks and almost failed. The task group parked a Cadillac Cimmaron at the gates on a rotating basis with a sign saying ''This prize in jeopardy.''
A third phase was an attempt to boost usage to 70 percent. The program lasted two months and involved parking a sleek red Camaro at the gates reminding employees they ''could win this prize.''
Still, it also nearly failed, with usage lagging at 68 percent in midtest. A midterm boost that included 500 coupons for free hamburgers at a nearby fast-food restaurant, along with other interim prizes, barely pushed usage above the limit.
Belt usage dropped immediately after the program. Significantly, though, it stayed well above the 36 percent usage when the project began. Last fall it averaged 59 to 60 percent, according to C. Tom Terry, environmental activities staff engineer who co-authored a Society of Automotive Engineers paper on the program.
''We treated it as a research project as much as anything else,'' Mr. Terry said. ''We kept turning up the gain,'' meaning raising the volume of the message to wear belts.
''The necessary ingredients for success are, first, a commitment from management that, 'yes, we are sincerely interested' in increasing belt usage. Second, a commitment from employees, such as the pledge card. And third, reachable goals had to be set.
''People have to know they're shooting for something attainable.''
And why the seat-belt program, anyway? GM points to the projected vast reduction in highway fatalities if everyone would wear seat belts. Observers of the industry have noted as well the carmaker's desire to show that voluntary seat-belt use can be increased.
The most-discussed alternative to voluntary belt use, the air bag, is a safety system that could significantly increase car prices.