Thanks to a unanimous vote of California’s Occupational Safety and Health Standards Board last Thursday, workers get to hold on to a robust chemical right-to-know rule that puts their health and safety first. The vote also means that California workers will reap the benefits of more meaningful right-to-know rules than those at the federal level.

“It’s a human right to know about the hazards of the work you’re doing,” said Dorothy Wigmore, occupational health specialist at Worksafe, a state-based organization dedicated to eliminating workplace hazards. “If employers don’t know about the hazards of the chemicals in the workplace, and if workers don’t know about those hazards, how can we prevent people from getting sick and dying? For me, that’s why it’s a fundamental issue in health and safety.”

Thursday’s vote concerned California’s Hazard Communication (HazCom) rule and whether the state should have blunted its regulation in favor of coming in line with less stringent rules that the federal Occupational Safety and Health Administration adopted in 2012. California’s 1980 HazCom law predates the federal one by three years. Wigmore told me that it goes back to a group of workers who discovered that the DBCP pesticide they were making was causing their infertility.

Under right-to-know laws, manufacturers and suppliers decide if ingredients in their chemical products are hazardous and produce data sheets and labels to provide information about those effects and guidance about how to use the product. Employers must tell workers about the hazards and train them about how to use the product safely as well as how to use the data sheets and labels.

The California rule will continue to require those preparing data sheets and labels to use several ”floor lists” about toxic chemicals. It also employs a one-study threshold for disclosing health hazards, which means that just one positive study, done using “established scientific principles,” is reason enough to inform workers of a possible hazard.

The recent question before California’s Occupational Safety and Health Standards Board was this: How should California revise its chemical right-to-know rule to be at least as effective as the federal OSHA standard that adopted parts of the international agreement called the Globally Harmonized System of Classification and Labeling of Chemicals (GHS). The GHS is supposed to replace the varying systems that countries use to classify hazardous chemicals with uniform categories and criteria. Data sheets and labels should be the same around the world.

But adopting just the federal standard would leave California workers without information based on authoritative lists or the one-study rule. The GHS agreement — and federal OSHA — dropped both requirements in favor of the “weight of evidence” approach. That approach allows manufacturers to decide what studies they will accept — in other words, unethical manufacturers could cherry-pick studies that suit their interest, Wigmore said.

Not surprisingly, the chemical industry was in favor of the California board voting to go the way of federal OSHA. On the other hand, Worksafe and more than 50 other organizations representing unions, public health and environmental health groups supported Cal/OSHA’s efforts to retain important parts of the current regulation. Worksafe predicted that the change would “lead to a ‘wild west’ of (safety data sheets) that may be nicely formatted but cannot be trusted to have full and accurate information about hazards.”

“For workers, what’s at stake is do we really have the right to know about the hazards of the chemicals we use on the job,” Wigmore said. “It’s a substantial weakening of a worker’s right to know…Just adopting the 2012 federal standard would have taken us back many years, in my humble opinion.”

In a letter to the chair of the board, Wigmore noted that under GHS, the “’weight of evidence’ doesn’t always weigh the same.” The Worksafe website offers this example:

Consider the case of styrene, a chemical considered carcinogenic by the National Toxicology Program, along with a host of other hazards. The chemical’s data sheets from Chevron Phillips, an international company, differ from country to country, although they were all apparently prepared on the same day by the same department. In China, for instance, the data sheet indicates that styrene belongs to four GHS health hazard categories, while the Japanese sheet list 14, the Korean sheet has 10, and the U.S. sheet has nine health hazard categories listed.

In fact, the U.S. 2011 Chevron styrene data sheet said the chemical met the GHS criteria for carcinogenicity. That’s gone in 2014, as though the “weight of evidence” has mysteriously shrunk in the United States.

If a multinational company like Chevron “harmonizes” its labels and data sheets to what they can get away with in a particular jurisdiction, what will others do? How can the chemical industry be trusted to provide complete and accurate information about their products without being told to use authoritative lists for carcinogens and other health hazards? How can they be trusted to use exceptions properly?

The answer, of course, is that they can’t.

Fortunately, California’s board responsible for health and safety sided with workers last week. Some board members also picked up on the message from many worker and public health advocates: the changes are necessary but not sufficient, and improvements are needed.

“Worksafe has been fighting for workers’ right to know for years and we’re not going to give up,” Wigmore said. “They haven’t heard the last of us.”

To learn about California’s right-to-know rules, visit Worksafe. Submissions made to Cal/OSHA’s advisory committee meeting can be found at the agency website.

Many thanks to Dorothy Wigmore for her help and contributions to this article.

Kim Krisberg is a freelance public health writer living in Austin, Texas, and has been writing about public health for more than a decade.