The results of nearly a decade of preliminary work will be evident this month when the very first session of the United Nations Subcommittee on the Globally Harmonized System of Classification and Labeling of Chemicals (GHS) takes place in Geneva, Switzerland. This new organization will work to establish an international classification and labeling system, which would include material safety data sheets (MSDSs) and readily recognizable symbols for all chemicals that present health or environmental hazards.

Several international agencies have taken responsibility for specific parts of the project. Overall coordination is the responsibility of the Inter-Organization Programme for the Sound Management of Chemicals, a group established in 1995 to coordinate efforts of intergovernmental organizations in the field of chemical safety.

The Organization for Economic Cooperation and Development (OECD) has drafted criteria for rating health and environmental hazard levels based on toxicity, skin and eye irritation or corrosivity, respiratory sensitivity, and whether substances are mutagens or carcinogens. Some of these hazard classes are already regulated in transportation in countries that have adopted the U.N. Model Regulations on the Transportation of Dangerous Goods. The difference is that the GHS proposal addresses chronic hazards as well as acute hazards and will extend beyond transportation into the workplace and consumer arenas.

The U.N. Committee of Experts on the Transportation of Dangerous Goods (UNCOE) will be responsible for developing criteria for identifying physical hazards such as flammability. And the International Labour Organization (ILO) will present a proposal for a hazard-communication system that would include markings and labels that could be recognized in any language.

The GHS system is intended to augment existing systems in order to enhance safety and environmental protection, not replace current classification and labeling requirements for the transportation of dangerous goods. But many transportation experts are expressing concern regarding the direction in which the project seems to be heading. For one thing, the hazard-classification system proposed by the ILO would include numerous new "hazard levels" in addition to the class, division, and packing-group levels in use today. For example, oral acute toxicity would be divided into five hazard levels, flammable liquids would have four levels, and carcinogens would have three levels. Each level would require different "signal words" and "precautionary statements" on package markings and on a prescribed MSDS form. In addition, the ILO's labeling proposal includes the use of pictograms or symbols within a diamond-shaped border with a background pattern or color to signify each hazard.

And there's the rub. Under the proposed specifications, these labels would be almost identical to the existing hazard-class labels in color, content, and shape. That could be confusing because in many cases, they will be displayed on packages that are not regulated as dangerous goods for transportation purposes, which could lead carriers to look for shipping papers, placards, and ID numbers when these items are not required. As a result, the carrier might refuse a perfectly legal shipment.

Although all participants in this project should be commended for their efforts to enhance safety, protect health, and preserve the environment, the end result could well be counterproductive if excessive complexity and the resulting confusion impede commerce.