A new government drive to crack down on major occupational health and safety hazards instead of "nitpicking" small businesses with "Mickey Mouse" regulations was announced yesterday by Labor Secretary Ray Marshall.

"There will be no more petty regulations like those dealing with coat hooks in bathrooms . . . We're going to stop the absurd practice of printing 15 pages of regulations, in small type, on the safety of ladders," Marshall said in outlining what he described as a "new era" for the often criticized and ridiculed Occupational Safety and Health Administration.

Industry had criticized OSHA for harassing businesses with trifling but burdensome safety rules, and organized labor has accused OSHA of ignoring serious health hazards, and Marshall said both are right.

"The worst thing about wasting time and money on nitpicking regulations," said the secretary, "is against the most serious dangers to human life and limb in high-risk workplaces."

Key elements of the new policy as unveiled at a press conference by Marshall and Eula Bingham, the new OSHA chief, includes:

Devoting 95 per cent of OSHA's inspections, instead of the current 80 to 85 per cent, to such high-risk industries as construction, manufacturing, transportation and petrochemicals.

Substantially reducing inspections of small businesses engaged in less dangerous work (an estimated 80 per cent of the total of all small businesses), although auto repair shops, dry cleaners, building materials stores and other more hazardous small businesses will face increased inspection.

Stressing development of health regulations for broad categories of potentially deadly dangers, such as cancer-causing substances, rather than detailed prescriptions for individual job risks - epitomized by OSHA's 35 pages of rules on the design of "Exit" signs.

Simplifying regulations that are "needlessly detailed, complicated or unclear" and eliminating others that are outdated or unnecessary, many of which were designed as guildlines by private groups or other governmental agencies an imposed as OSHA regulations by congressional directive.

Suspending penalties for standards violations that "have nothing to do with worker health or safety" until the standards are rewritten or revoked.

Offering handbooks with simple check lists and other self-help guides, professional consultative services and an increased educational effort to encourage voluntary compliance.

"We are going to stop trying to regulate every detail of life in every office, store and factory . . . We are going to simplify our regulations so that everyone can understand them . . . Instead of regulating by fiat, we're going to stress preventative consultations with small business," Marshall said.

But mainly, he said, "we're going to focus our efforts on the real health and safety problems which American workers face."

Marshall said yesterday's announcement was aimed at part in proving that "me mean business" to OSHA's critic's, smeow whom have been pushing in Congress to repeal the six-year-old program.

He said the OSHA changes he was announcing have the "strong backing" of President Carter, who has said he wants to "enforce the law rigidly" but with "a maximum amount of support from labor and industry." Marshall said with a smile: "What the President has a strong interest in I have a strong interest in."

The immediate reaction to Marshall's announcement was positive.

The U.S. Chamber of Commerce said the changes were "highly welcome" and a "step in the right direction," especially the emphasis on consultation to encourage voluntary compliance.

AFL-CIO spokesman Albert J. Zack said the approach was "excellent, sound and sensible."

Asked at the press conference why he believed he could change OSHA when his predecessors failed despite repeated efforts, Marshall said, "We believe in this law . . . the previous administrations did not."

Holding out a yardstick by which new program can be measured, Bingham said "substantial progress" should be discernible in three months and "even more progress" in a year. Yesterday's action was the second major step to strengthen OSHA since Marshall and Bingham took over. Last month they announced a 90 per cent reduction in permissible worker exposure to benzenc, a chemical believed to cause leukemia.