The chairman of the Consumer Product Safety Commission said yesterday that the agency may be overstating the degree of hazard in consumer products by paying too little attention to the user's role in causing injuries.

Speaking before the Better Business Bureau of Metropolitan Washington Inc., Terrence M. Scanlon called for a change in the safety agency's system of gathering statistical information.

Scanlon said that the injury-collection system could be improved by asking additional questions of emergency room patients to learn how their personal behavior relates to an accident, rather than just using emergency room statistics for every consumer-related accident.

"If, for instance, someone picks up a lawnmower and uses it to trim their hedge, cutting off several fingers in the process, that can hardly be considered the fault of the lawnmower, or of the manufacturer who produced it," Scanlon said.

Under the current method, the National Electronic Injury Surveillance System, officials in 64 hospital emergency rooms around the country collect statistics on everyone brought in for a product-related injury. CPSC later examines this information to determine whether the injury was caused by the product.

Scanlon has said he wants emergency room officials rather than the CPSC to determine whether the injury was product-related or caused by the victim. Consumer groups have argued that many defective products, such as certain types of lawnmowers, never would have been discovered if the CPSC had not been alerted by statistics compiled under the current system.

Scanlon said the CPSC had conducted a pilot program in eight hospital emergency rooms to obtain more data about the behavioral aspects of product-related accidents. "We should have the results shortly and, if they look promising, I will urge the commission to collect behavioral data in all the emergency rooms that participate," he said.

In another consumer-related development yesterday, a local consumer group called on the CPSC to require that all children's toys be labeled to indicate potential hazards and the minimum age at which the toy can be used safely.

The Americans for Democratic Action Consumers Affairs Committee petitioned the CPSC yesterday to develop clear and informative toy labeling and replace what it called the "totally haphazard" voluntary age labeling used now by the toy industry.

"The commission is not doing all that it could to curtail the risk of injury," said Ann Brown, chairman of the ADA Consumer Affairs Committee, the group that annually rates the safety of toys. Brown called the CPSC statistics of more than 118,000 toy-related injuries reported in hospital emergency rooms in 1983 "just the tip of the iceberg" because they don't include the unreported toy-related injuries or those reported only to private physicians.

ADA, which emphasized that it was criticizing the labels -- not the toys -- said that it wants every toy-related package to specify at what age a child can or cannot play safely with a toy, why a toy is hazardous and what part could cause an injury.

ADA, for example, said a label for the Fisher-Price toy, Construx, would be better if its age label was not printed in tiny letters. The label of Hasbro Industries Inc.'s refill pegs for its "Lite Brite" construction toy also was criticized by ADA for stating that the toy is for ages 4 to adult, and not indicating that the toy should be kept away from children under four years old because its small parts could be swallowed.

ADA also released a limited survey indicating that toy purchasers do not understand current labeling and would favor more explicit warnings to aid them in selecting toys. According to the survey conducted during April 1985, 73 percent of about 60 adults surveyed believe current age labeling pertains to ability or intelligence levels, and not danger or risk of injury.

The Toy Manufacturers of America and the CPSC said that they had not seen the petition nor had ADA discussed it with them. But Douglas Thomson, president of the toy industry group, said it opposes mandatory regulations and instead supports voluntary action by industry.

"The cost is not the issue," said Thomson "It's just unnecessary regulation. I think the voluntary standards in place for age labeling now work."

Scanlon said he also supports voluntary, rather than mandatory, standards for toy age/risk labeling. "The commission has no specific data on injuries caused by the lack of age labeling," he said.