Using A Percent Range on an SDS? OSHA Answers
Written By: Atanu Das on Wednesday, December 21, 2016
In 29 CFR 1910.1200, Appendix D, OSHA requires that chemical manufacturers and importers disclose in Section 3 of the SDS, Composition/information on ingredients, the chemical name and concentration (exact percentage) of all ingredients present in a mixture which are classified as health hazards. Ingredient concentrations are required to be disclosed if they are present above their cut-off value/concentration limits or if they present a health risk below the cut-off value/concentration limits. The concentration (exact percentage) must be specified unless a trade secret claim is made, when there is batch-to-batch variability in the production of a mixture, or for a group of substantially similar mixtures with similar chemical composition. In these cases concentration ranges may be used.
Batch-to-batch variability occurs when the mixture has a set formula but there may be some very small differences among the batches that occur during the production process. To use a range in this situation, these variations must have no impact on the hazard of the overall mixture. For example, the formula may require 4.0 pounds of a chemical, but as produced the final product varies by ± 0.1 pound from that specification. In this case, assuming the high end of the variation does not change the hazard classification, the SDS preparer may choose to use either the concentration set in the formula or the concentration range anticipated between the batches.
In addition, a range of concentrations may be used in situations where a chemical manufacturer or importer may have a line of products that are very similar, but can vary slightly in composition to meet the needs of customers. For example, toner colors may be changed by the amount of pigment present in the mixture. Another example is the blending of dry materials where the ingredients are the same. In these cases, the hazards remain the same, even though there may be small differences in the amounts from product to product. For these substantially similar mixtures, providing that the composition differences are minimal and the hazards remain the same, concentration ranges may be used for multiple, similar products.
The standard allows chemical manufacturers and importers to claim the specific chemical identity and/or the exact percentage of a hazardous ingredient in a mixture as a trade secret. If the exact percentage of a hazardous ingredient in a mixture is withheld, a concentration range may be used in its place. The use of a concentration range in this case would assist downstream users in providing appropriate protections and, at the same time potentially eliminate requests from users for disclosure of the trade secret in accordance with §1910.1200. Trade secret status may be claimed for exact percentage composition but not for concentration ranges. For example, when using a concentration range due to batch-to-batch variability you cannot claim the range as a trade secret on the safety data sheet.
In general, if a classifier uses a range of concentrations on the SDS, OSHA expects that the range will be sufficiently narrow to meet the intent of disclosing the actual concentration range, provided that the range is an accurate representation of the variation. A range of 1%-99%, for instance, would not be an acceptable range. Concentration ranges, if used, must be based on the information available to the classifier, such as analysis results, product specification, or nature of the process, and the high end of the range used may not change the reported hazard classification.
More info can be found on the OSHA site