HazCom, short for Hazard Communication, is a federal workplace safety standard that requires employers to inform workers about the hazardous chemicals they may be exposed to on the job. Codified as 29 CFR 1910.1200 and enforced by OSHA, the standard covers everything from how chemicals are classified and labeled to how safety information is organized and shared. It consistently ranks among OSHA’s top 10 most frequently cited violations, making it one of the most important regulations for any workplace that handles chemicals.
What HazCom Requires
The core idea behind HazCom is straightforward: every hazardous chemical produced or imported into the United States must be classified by its hazards, and that information must reach the employers and employees who work with it. The standard accomplishes this through three interconnected requirements that form what safety professionals sometimes call the “HazCom triad”: labels on chemical containers, Safety Data Sheets for every hazardous product, and employee training.
Employers who use hazardous chemicals in their workplaces must also maintain a written hazard communication program. This document spells out how the company handles labeling, where Safety Data Sheets are kept and how workers can access them, and what the training program looks like. It must include a complete list of every hazardous chemical present in the workplace.
Chemical Labels and What’s on Them
Every container of a hazardous chemical that leaves a manufacturer or distributor must carry a label with six specific elements:
- Product identifier: the name used to identify the chemical, matching what appears on the Safety Data Sheet
- Signal word: either “Danger” for more severe hazards or “Warning” for less severe ones
- Hazard statements: standardized phrases describing the nature of the hazard (for example, “causes serious eye damage”)
- Precautionary statements: recommended measures to minimize exposure or harm
- Pictograms: red-bordered diamond symbols depicting hazard types like flames, skulls, or exclamation marks
- Manufacturer information: the name, address, and telephone number of the company responsible for the chemical
These label elements follow the Globally Harmonized System (GHS), an international framework that standardizes chemical hazard communication across countries. Before GHS adoption, a chemical might carry completely different warnings depending on which country it was sold in. The standardized pictograms and signal words mean a worker in the U.S. sees the same hazard symbols as a worker in Japan or Germany.
Safety Data Sheets: The 16-Section Format
A Safety Data Sheet (SDS) is the detailed reference document for any hazardous chemical. Every SDS follows a standardized 16-section format so workers and emergency responders can quickly find the information they need, regardless of the product or manufacturer.
The first three sections cover identification and hazards. Section 1 lists the product name, recommended uses, and the manufacturer’s contact information including an emergency phone number. Section 2 lays out the hazard classification, signal word, pictograms, and hazard statements. Section 3 breaks down the chemical composition, listing ingredients by name and concentration along with unique identifiers like CAS numbers.
Sections 4 through 8 deal with emergency response and safe handling. Section 4 describes first aid measures organized by how exposure happened: inhalation, skin contact, eye contact, or ingestion. Section 5 covers firefighting, including which types of extinguishers work and which don’t. Section 6 addresses spill cleanup procedures. Section 7 outlines safe handling and storage practices, including which chemicals should never be stored together. Section 8 specifies exposure limits and what protective equipment workers should use.
The remaining sections cover physical and chemical properties, stability and reactivity, toxicological data, ecological information, disposal considerations, transport information, regulatory information, and other relevant details. Employers are required to keep SDSs accessible to workers during their shifts, whether that means a binder in the work area or an electronic system employees can pull up on demand.
Health Hazards vs. Physical Hazards
HazCom divides chemical hazards into two broad categories. Health hazards affect the body and include things like skin irritation, sensitization (allergic reactions that develop over time), organ damage, and carcinogenicity. Physical hazards relate to the chemical’s behavior in the environment: flammability, explosibility, corrosion to metals, and reactivity with other substances.
The 2024 update to the standard refined several of these classifications. The criteria for skin corrosion, eye damage, and flammable gases were all updated, and a new hazard class for desensitized explosives was added. The update also incorporated non-animal testing methods for skin corrosion and irritation assessments, reflecting broader changes in how chemical safety testing is conducted.
Employee Training
Labeling chemicals and maintaining SDSs only works if employees understand how to use that information. HazCom requires employers to train workers on the hazards of the chemicals in their work area, how to read and interpret labels and Safety Data Sheets, and what protective measures are in place. Training must happen before a worker is first exposed to hazardous chemicals, and additional training is required whenever a new chemical hazard is introduced to the workplace.
The training doesn’t need to cover every chemical individually. Instead, it should give workers the tools to understand hazard categories and look up specifics on their own. A worker who knows what a flammability pictogram means and where to find the SDS can handle encountering a new product without starting from scratch.
What HazCom Doesn’t Cover
Several categories of products are exempt because they’re already regulated under other federal laws with their own labeling requirements. Pesticides fall under EPA regulations. Foods, drugs, cosmetics, and medical devices are covered by FDA rules. Consumer products regulated by the Consumer Product Safety Commission, alcoholic beverages, tobacco products, and hazardous waste managed under environmental cleanup laws are all excluded as well. The logic is simple: these products already have labeling systems tailored to their specific risks, so layering HazCom requirements on top would create confusion rather than clarity.
The 2024 HazCom Update
OSHA published a final rule on May 20, 2024, updating the Hazard Communication Standard to stay aligned with the latest revision of the GHS. The rule took effect on July 19, 2024, but compliance is being phased in over several years.
Beyond the updated hazard classifications, the rule added flexibility for labeling in specific situations. Bulk shipments in tanker trucks, railcars, or intermodal containers now have adjusted labeling provisions. Small containers of 100 milliliters or less, and very small containers of 3 milliliters or less, also got tailored requirements that account for limited label space. The rule also addressed a long-standing issue with trade secrets by allowing manufacturers to use prescribed concentration ranges when withholding exact ingredient concentrations.
The compliance timeline gives chemical manufacturers and importers 18 months from the effective date to update labels and SDSs for single-substance products, with employers getting an additional 6 months after that to update their workplace labels, programs, and training. For mixtures, the deadlines extend to 36 months for manufacturers and 42 months for employers. During the transition, companies can comply with either the previous version of the standard or the new rule.
Why HazCom Violations Are So Common
Hazard Communication appeared on OSHA’s top 10 most frequently cited standards list for fiscal year 2024. The violations tend to cluster around a few recurring issues: missing or outdated Safety Data Sheets, containers without proper labels, incomplete written programs, and inadequate employee training. These are largely administrative failures rather than dramatic safety breakdowns, but they add up. A worker who encounters an unlabeled container or can’t access an SDS during a spill is working without the information they need to protect themselves. For employers, keeping a current chemical inventory, ensuring every container is labeled, and documenting training are the most practical steps to staying in compliance.