Safety data sheets for diluted chemical mixtures

July 24, 2018

Mr. Larry Lucas

[Recipient address omitted]

Dear Mr. Lucas:

Thank you for your letter to the Occupational Safety and Health Administration’s (OSHA) Directorate of Enforcement Programs, regarding OSHA’s Hazardous Communication Standard (HCS), 29 CFR 1910.1200. This letter constitutes OSHA’s interpretation only of the requirements herein and may not be applicable to any situation not delineated within your original response. Your question has been summarized below, followed by our reply.

Background: Environmental consultants often employ analytical laboratories to characterize environmental water samples they collect. Environmental water samples are commonly acidified (pH < 2) before transit to analytical laboratories. Nitric acid is a common preservative used for water samples as it preserves most trace metals, and reduces precipitation, microbial activity, and sorption.

Question: Instead of listing the physical and chemical properties of a diluted chemical as it exists in a mixture, is it acceptable to list the physical and chemical properties of the concentrated chemical and note that the product being classified contains only X% of that chemical? For example, is it acceptable to list the physical and chemical properties for concentrated (68%) nitric acid for an environmental water sample which has been acidified to approximately 5% nitric acid in safety data sheet (SDS) Section 9, Physical and chemical properties?

Reply: No. The HCS requires the safety data sheet to include the physical and chemical properties of the hazardous chemical. 29 C.F.R. § 1910.1200(g)(2)(ix). These properties are the empirical data of the actual substance or mixture, based on observations or tests performed on the chemical. Concentrated (68%) nitric acid has different physical and chemical properties than an environmental water sample that has been acidified to approximately 5% nitric acid, and therefore it would be inaccurate to provide the chemical and physical properties for concentrated (68%) nitric acid in section 9 of the SDS.

The HCS 2012 requires the manufacturer or importer (i.e., environmental consultants) to properly label samples and provide an accurate SDS to ensure that the correct hazard information is communicated to downstream users. For many chemicals, the data related to physical and chemical properties has already been compiled and is readily available from sources such as OSHA’s Occupational Chemical Database, CRC Handbook of Chemistry and Physics, Organization for Economic Cooperation and Development (OECD) eChem Portal, and trade associations. Where information required to be included in Section 9 of the SDS is not relevant or not available, a note to that effect must be made in Section 9 for that property.

Please be aware that the Maryland Department of Labor, Licensing & Regulation (DLLR) operates its own OSHA-approved occupational safety and health program called the Maryland Occupational Safety and Health (MOSH). MOSH adopts and enforces standards and investigates safety and health concerns in workplaces throughout the state. State Plans are required to have standards and an enforcement program that are “at least as effective” as OSHA’s, but may have different or additional requirements. Please contact MOSH directly at the address below, for further information and to discuss your specific compliance issue:

Maryland Department of Labor, Licensing & Regulation (DLLR)

Maryland Occupational Safety and Health (MOSH)

10946 Golden West Drive, Suite 160

Hunt Valley, MD 21031

Telephone: (410) 527-4499

https://www.dllr.state.md.us/labor/mosh/volc.shtml

Thank you for your interest in occupational safety and health. We hope you find this information helpful. OSHA’s requirements are set by statute, standards, and regulations. Our letters of interpretation do not create new or additional requirements but rather explain these requirements and how they apply to particular circumstances. This letter constitutes OSHA’s interpretation of the requirements discussed. From time to time, letters are affected when the Agency updates a standard, a legal decision impacts a standard, or changes in technology affect the interpretation. To ensure that you are using the correct information and guidance, please consult OSHA’s website at http://www.osha.gov. If you have further questions, please feel free to contact the Office of Health Enforcement at (202) 693-2190.

Sincerely,

Thomas Galassi, Director

Directorate of Enforcement Programs