The U.S. Court of Appeals for the District of Columbia yesterday gave the Occupational Safety and Health Administration 30 days to propose a tighter standard for worker exposure to ethylene oxide, a chemical widely used to sterilize hospital equipment.

In its decision the three-judge appeals panel said the absence of even an OSHA notice of proposed rulemaking, 18 months after it announced that it would begin working on a rule, was unreasonable.

However, the panel overturned a lower court order requiring OSHA to publish an emergency standard that would have taken effect immediately. The appeals panel set no firm timetable for a final rule, but said "we expect" one "within a year's time."

The agency's most recent estimate on the publication of the final rule is the fall of 1984.

"Three years from announced intent to regulate to final rule is simply too long given the significant risk of grave danger ethylene oxide poses to the lives of current workers and the lives and well-being of their offspring," the panel said. "Delays that might be altogether reasonable in the sphere of economic regulation are less tolerable when human lives are at stake."

The International Agency for Research on cancer in 1980 listed ethylene oxide as a "probable" cancer-causing agent when inhaled. Another study showed that workers exposed to concentrations of 36 parts per million suffered chromosomal damage. The agency's existing ceiling is 50 parts per million averaged over an eight-hour day. An estimated 140,000 U.S. hospital workers are exposed to the chemical.

The judges also noted that, when OSHA originally rejected a petition for an emergency temporary standard in September, 1981, it conceded that the current exposure limit "may not be sufficiently protective."

OSHA released a statement by Assistant Labor Secretary Thorne G. Auchter saying: "We are pleased that today's decision reverses the lower court's order and agrees with us that an emergency temporary standard for ethylene oxide is not appropriate."