The new chairman of the Consumer Product Safety Commission said yesterday that while she preferred to have industry set voluntary standards she was not afraid to regulate.

"I will regulate if necessary," Nancy Harvey Steorts, said in her first interview since taking office a month ago.

"If there is a reason to regulate, as chairman of this CPSC I will regulate," Steorts said, making it clear for the first time since she was named to the post that she does not intend to relax the agency's rule-making functions, as some CPSC commissioners and staff members had feared.

Even so, Steorts said mandatory rules and bans would be imposed only after all efforts failed to get industry groups to do the job on their own.

"If there is a situation where there is an opportunity for an industry to develop -- with the assistance of the consumer -- a voluntary standard, I would certainly support that and encourage that effort," she said. "However, if the voluntary standard approach did not work -- or if the industry was not willing to go along with a voluntary effort -- then I think that's the time we take a very hard look and strong look at a mandatory regulation."

Banning a product would come "if there is no other alternative . . . if there is not a a solution to making that product safe," she added.

Working more closely with industry is one of Steorts' two top priorities. The other is to develop a better relationship with consumers at the grassroots level. To do this, the 44-year-old chairman has won the approval of the other four CPSC commissioners to reorganize the agency and shift much of its power from the headquarters in Washington to the agency's field offices across the country.

This shift in power, however, comes at a time when the agency has decided to eliminate five of its 10 regional offices. Nonetheless, Steorts contends that the remaining regional offices will be able to play a strong role in bringing the views of consumers and industries to the commission, and in educating the public about unsafe products even more than the commission has done in the past.

Although Steorts has been involved in consumer issues since the mid-70s when she was a special assistant for consumer affairs to Agriculture Secretary Earl Butz, she said she did not come to the commission with "specific issues" or a firm agenda.

Steorts did make it clear, however, that she believes the commission should continue to regulate products that have cancer-causing chemicals -- even though some business groups have argued that the agency should not be involved in this area. "The chronic-hazards program is important to the commission," Steorts said.

Additionally, the chairman indicated that like her predecessor, Susan King, she does not believe that manufacturers should be allowed to export products that have been banned in the United States, such as pajamas that have been treated with the flame-retardant chemical Tris. "I feel strongly that what we're sending outside our country is safe, and I will do everything in my power to make sure that is the case," she said.

Steorts also said she firmly believes in the independence of the agency and does not believe that it should be folded into another Cabinet department where the president could have tighter control over it.

Even though Reagan administration officials argued for such a move earlier this year, Steorts said "I really fully hope this agency will continue as an independent agency. That's the way it's mandated from Congress, and it should continue that way."