The hazard communication standard is also known as HazCom or the Right-to-Know Law

Last updated 2026-07-09

What is the hazard communication standard also known as?

The OSHA hazard communication standard goes by three names, and you'll hear all three used for the same rule: HazCom, the HazCom Standard, and the Right-to-Know Law. The formal citation is 29 CFR 1910.1200. OSHA sometimes shortens it to HCS. ^[1]

The "Right-to-Know" nickname comes from the original 1983 version of the rule, built around one idea: workers have the right to know what chemicals they handle and what those chemicals can do to them. That framing stuck. Some state agencies still put "Right-to-Know" on their own regulations, which trips people up, because a handful of states have separate state-level right-to-know laws that go well past OSHA's federal floor.

"HazCom" is what safety professionals, industrial hygienists, and OSHA compliance officers actually say out loud. When someone in a compliance meeting says "your HazCom program," they mean the whole package: your written hazard communication program, your SDS binder, your labels, and your training records.

The third layer of terminology is the Globally Harmonized System, or GHS. In 2012, OSHA revised HazCom to match the UN's GHS framework for classifying and communicating chemical hazards. ^[2] People sometimes call it "HazCom 2012" or "GHS-aligned HazCom" to separate the current version from the older pre-GHS standard. OSHA published a further update in 2024, often called "HazCom 2024," which sharpens the rules around physical hazards and flammable gases, among other changes. ^[3]

What does 29 CFR 1910.1200 actually require?

The standard has five core requirements. Miss any one and you're looking at a citation. Here they are in plain terms.

First, a written hazard communication program. This document explains how your specific workplace handles chemical identification, labeling, SDS management, and employee training. It has to be site-specific, not a generic template with your company name pasted on top. OSHA says it must be "available to employees, their designated representatives, the Assistant Secretary and the Director" under 29 CFR 1910.1200(e)(4). ^[1]

Second, a chemical inventory. Every hazardous chemical in the workplace gets listed. This list is the backbone of the whole program.

Third, Safety Data Sheets (SDSs) for every chemical on that list. SDSs replaced the old Material Safety Data Sheets (MSDSs) under the 2012 revision and now follow a standardized 16-section format. ^[2] An SDS has to be reachable during every shift, which usually means a binder in a known spot or an online system workers can actually pull up from the floor.

Fourth, labels. Every container of a hazardous chemical needs one. Under the GHS-aligned standard, primary container labels need a product identifier, a signal word ("Danger" or "Warning"), hazard statements, precautionary statements, pictograms, and supplier information. ^[1]

Fifth, training. Every employee who works with or near hazardous chemicals gets it. Training has to cover how to read an SDS, what the label elements mean, and the specific hazards in that worker's area. This isn't a one-time-at-hire checkbox. If a new hazardous chemical shows up, training happens before anyone is exposed.

Construction workers fall under a parallel standard at 29 CFR 1926.59, which pulls in 1910.1200 by reference. ^[4] Maritime has its own versions at 29 CFR 1915.99, 1917.28, and 1918.90.

Who does the hazard communication standard cover?

HazCom covers nearly every private-sector employer in the country whose workers may be exposed to hazardous chemicals. That's an enormous population. OSHA estimates more than 43 million workers across five million workplaces are affected. ^[5]

The standard covers employees who may be exposed under normal operating conditions or in a foreseeable emergency. "May be exposed" is a wide door. A janitor who mops with a bleach-based cleaner once a week counts. That employer needs an SDS for the cleaner and needs to train the janitor.

There are a few narrow exemptions. Hazardous waste under RCRA follows different rules. Tobacco products, unprocessed wood, and consumer products used in the same duration and frequency as a normal consumer would use them are technically exempt, though OSHA's enforcement history shows the agency reads the consumer-product exemption narrowly. ^[1]

Farm workers employed directly by their own family are exempt, as are federal agencies (which follow EPA and other rules instead of OSHA). State and local government employees are covered only if their state runs an OSHA-approved State Plan. There are 29 such State Plans as of 2024, covering roughly half the workforce. ^[6] If you're in California, Michigan, North Carolina, or another State Plan state, check whether your state stacks extra HazCom requirements on top of the federal ones.

For hazard communication basics and a checklist to audit your current program, that linked guide pairs well with this one.

What is the GHS and how does it relate to the Right-to-Know Law?

The Globally Harmonized System of Classification and Labelling of Chemicals (GHS) is a United Nations framework, not an OSHA rule. The UN published the first edition in 2003. The goal was one universal system for classifying chemical hazards and communicating them through labels and safety data sheets, so a worker in Mexico, in Germany, and in Ohio all see the same pictogram meaning the same thing. ^[7]

OSHA folded GHS into the hazard communication standard through the 2012 revision. The agency estimated the update would prevent 585 fatalities and 43,000 injuries a year once fully in place, and produce $2.4 billion in benefits through fewer injuries, better productivity, and lower costs. ^[5]

The difference from the old standard is real. The old MSDSs could be formatted however the manufacturer wanted. Some had 8 sections, some 16, some were barely legible. The GHS-aligned SDS now always runs exactly 16 sections in a fixed order, so a worker can flip to Section 8 for exposure limits and PPE on any SDS from any supplier. Section 2 always covers hazard identification. Section 11 always covers toxicology. That consistency saves real time when you need to look something up fast.

Labels got standardized too. There are nine GHS pictograms, the red-bordered diamonds with symbols inside: a skull and crossbones for acute toxicity, a flame for flammables, an exclamation mark for irritants, and so on. ^[2] These pictograms hold steady across all GHS-aligned countries, though each country picks which GHS "building blocks" to adopt, so some international variation remains.

How is HazCom different from a state Right-to-Know law?

This is a real source of confusion. The federal HazCom standard is sometimes called the Right-to-Know Law, but several states have their own separate right-to-know laws that are distinct from OSHA's standard.

New Jersey has the New Jersey Worker and Community Right to Know Act, which applies to employers and requires reporting to state agencies and municipalities beyond on-site training and SDS access. Massachusetts has the Massachusetts Right to Know Law, run by the Department of Labor Standards, with its own list of covered substances and labeling rules. Pennsylvania has the Worker and Community Right-to-Know Act.

These state laws can demand things the federal HazCom standard does not: community notification, reporting to local emergency planning committees, or coverage of substances that OSHA's hazard classification criteria wouldn't flag. Under Section 18 of the OSH Act, states with OSHA-approved State Plans must have standards that are "at least as effective" as federal OSHA, and they're free to go stricter. ^[6]

If your state has its own right-to-know law, you comply with both. The federal HazCom standard sets the floor. State law may raise it. Call your state's labor department or OSHA-approved State Plan agency directly to confirm what applies to you.

What did OSHA's 2024 HazCom update change?

OSHA published a final rule updating the hazard communication standard in May 2024, with phased compliance deadlines. ^[3] Compliance circles call it "HazCom 2024."

The major changes fix some genuinely messy classification problems left over from the 2012 version. Here's what shifted.

Flammable gases now have a more granular classification, separating gases that are both flammable and carry extra hazards (like being chemically unstable). That matters for anyone using acetylene, hydrogen, or liquefied petroleum gases.

Aerosols got their own standalone hazard category, split off from flammable liquids, because aerosol cans behave differently in a fire.

Some physical hazard criteria were updated to track the 9th revised edition of the UN GHS "Purple Book," the source document OSHA references. ^[7]

The 2024 rule also clarified when a mixture is "similar enough" to another mixture that you can rely on existing SDS data without new testing. That's practical relief for formulators.

Compliance timelines are phased. Chemical manufacturers and importers had until July 2026 to update labels and SDSs in most categories. Employers who use chemicals (rather than make or import them) get more time to update workplace labels and training. Check 29 CFR 1910.1200 or OSHA's HazCom webpage for the current phased deadlines, because these can move through enforcement policy letters.

Why is HazCom consistently OSHA's most cited standard?

HazCom lands in OSHA's annual top-10 most cited list year after year. ^[8] In fiscal year 2023, 29 CFR 1910.1200 generated thousands of citations across general industry.

The reasons are structural. HazCom has a lot of moving parts. You can have SDSs but no written program. You can have a written program but forget to update the chemical inventory when a new product arrives. You can have everything on paper but never actually train workers before exposure. Each gap is a separate citable item.

The most common HazCom violations OSHA documents: no written program or a weak one, missing or outdated SDSs, bad container labeling (especially on secondary containers filled from larger ones), and thin or undocumented training. ^[12]

For small businesses, secondary container labeling is the easiest thing to miss. An employee pours cleaner into a spray bottle and leaves it blank. That's a violation. The fix costs almost nothing: a label maker or a pre-printed template. It gets skipped constantly anyway.

The penalty math matters. A serious violation can run up to $16,131 per violation as of 2024, and OSHA adjusts these annually for inflation. ^[9] Willful or repeated violations can reach $161,323. One HazCom inspection with several citation items adds up fast for a small shop.

What does a compliant written HazCom program look like?

The written program is the piece most small businesses either skip or do halfway. Here's what yours actually needs to contain.

A list of the hazardous chemicals in each work area, or a pointer to where that list lives. It doesn't have to be exhaustive on day one, but it has to be current and reachable.

An explanation of how your company labels containers, including the system you use for secondary containers filled in-house. If you run a color code or a set label format, describe it.

A description of how your SDS system works: where SDSs are kept, who gets and updates them, and how employees reach them during all working hours.

A description of your training program: topics covered, who runs it, when new hires get trained, and when retraining happens.

Any non-routine tasks involving hazardous chemicals (cleaning inside a tank, say) need specific steps that address the hazards involved.

If contractors work on-site and might be exposed to your chemicals, your program has to explain how you'll share hazard information with them. This is the multi-employer provision, and it catches a lot of manufacturers and construction sites flat-footed.

If you've been chipping away at your written program and want a faster path to a complete, site-specific document, SafetyFolio's safety program generator builds compliant HazCom programs in about 15 minutes by walking you through your chemical inventory and work processes.

For a broader look at OSHA training requirements that sit next to your HazCom program, that guide covers the recordkeeping and documentation standards you'll want in place.

How do the 16 SDS sections work and which ones matter most day-to-day?

The 16-section format is required under the GHS-aligned HazCom standard. Every SDS from every supplier follows this structure. Here's a quick map of what's in each section and which ones your workers and supervisors actually need to find fast.

Section	Title	What's there
1	Identification	Product name, supplier contact, intended use
2	Hazard(s) Identification	GHS classification, signal word, pictograms, hazard statements
3	Composition/Ingredients	Chemical names, CAS numbers, concentrations
4	First-Aid Measures	What to do immediately after exposure
5	Fire-Fighting Measures	Extinguishing agents, special hazards
6	Accidental Release Measures	Spill cleanup, evacuation
7	Handling and Storage	Safe use practices, incompatibilities
8	Exposure Controls/PPE	PELs, TLVs, recommended respirator and gloves
9	Physical/Chemical Properties	Flash point, boiling point, vapor pressure
10	Stability and Reactivity	Conditions to avoid, hazardous decomposition
11	Toxicological Information	Routes of exposure, carcinogenicity, LD50 data
12	Ecological Information	(Not enforced by OSHA; EPA territory)
13	Disposal Considerations	(Not enforced by OSHA)
14	Transport Information	DOT/IATA classifications
15	Regulatory Information	Other applicable regulations
16	Other Information	Revision dates, preparer info

In a live emergency, workers need Section 4 (first aid) and Section 8 (exposure controls and PPE). Emergency responders want Section 5 (fire fighting) and Section 6 (spill response). Supervisors making purchasing or handling calls need Sections 2, 7, and 8.

OSHA does not enforce Sections 12 through 15 directly, but suppliers still fill them in because other agencies (EPA, DOT) do care about that information. ^[1]

What HazCom training is required and how long does it take?

The standard says training must cover the requirements of 29 CFR 1910.1200, how to detect chemical releases in the work area, the physical and health hazards of the chemicals present, protective measures workers can take, and how to read labels and SDSs. ^[1] There's no minimum duration. No "you must train for two hours" rule exists.

What OSHA requires is that the training be effective. That word "effective" shows up in OSHA letters of interpretation, and it means the worker actually understands the material, not that you played a video and collected a signature. In practice, inspectors test effectiveness by asking workers questions during walkthroughs. If a worker can't say what an SDS is or where to find one, that's a training failure no matter what your records claim.

For most workplaces, solid initial HazCom training runs 30 to 90 minutes, depending on how many hazard classes are present. A paint shop with solvents and aerosols needs more depth than an office that stocks a few commercial cleaners.

Retraining is required when a new hazard shows up, not on a fixed annual clock. Even so, many safety professionals run annual refreshers because workers forget and workplaces change.

Training records need to document who was trained, when, on what topics, and who did the training. A sign-in sheet plus a training outline is a bare-minimum record. Written tests or competency checks are stronger evidence if an inspector ever shows up.

For an overview of OSHA 30 training and how it ties into chemical safety, that piece covers what supervisors should know past the HazCom basics.

How do OSHA's PELs and ACGIH TLVs appear in HazCom compliance?

Section 8 of every SDS lists exposure limits, and this is where two different systems sit side by side: OSHA Permissible Exposure Limits (PELs) and ACGIH Threshold Limit Values (TLVs).

OSHA's PELs are legally enforceable under 29 CFR 1910.1000 (for air contaminants) and substance-specific standards. ^[10] Suppliers have to list PELs on the SDS when they exist. The catch is that OSHA's PELs are badly out of date. Most were adopted in 1971 from 1968 ACGIH TLVs and have barely moved since. OSHA tried to update 428 PELs at once in 1989 and lost in court (AFL-CIO v. OSHA, 11th Circuit, 1992), which scared the agency off large-scale PEL updates for decades.

ACGIH, the American Conference of Governmental Industrial Hygienists, publishes TLVs every year based on current health science. ^[11] TLVs aren't legally enforceable by OSHA unless a compliance officer uses the General Duty Clause (Section 5(a)(1) of the OSH Act) to cite a hazard where no PEL exists. In practice, TLVs protect workers better than PELs for most substances. If your SDS shows a PEL of 200 ppm and a TLV of 20 ppm for the same substance, the TLV is telling you something the PEL won't.

Good industrial hygiene practice targets TLVs (or NIOSH RELs) rather than the bare OSHA PEL. For your HazCom program, this mostly shapes how you spec engineering controls and PPE, both of which get documented in Section 8 of the SDS and in your written program's PPE provisions.

For more detail on a specific chemical SDS, the HCl safety data sheet guide walks through a real one in full.

What penalties does OSHA assess for HazCom violations?

OSHA adjusts its civil penalty amounts every year with a cost-of-living formula. For fiscal year 2024, the per-violation maximums are $16,131 for a serious violation, $16,131 for an other-than-serious violation, $16,131 per day for failure to abate, and $161,323 for willful or repeated violations. ^[9]

In practice, OSHA knocks proposed penalties down based on employer size, good faith, and history. A small employer (under 25 employees) with no prior violations who cooperates during the inspection usually sees big reductions off the maximum. That doesn't make the fines small. A single inspection that finds five separate HazCom citation items at $5,000 each is a $25,000 bill before any abatement costs.

The most common path to a lower penalty is an informal conference with OSHA after you get the citation. This is a standard step, not an admission of guilt, and most employers who go through it see penalties cut 15 to 50 percent in exchange for a corrective action plan and faster abatement.

If you're building a HazCom program after a citation, document everything: dates of correction, who did what, and what training happened. OSHA's abatement verification looks for exactly that paper trail.

For a practical look at how OSHA inspections actually run and what your rights are during one, that overview covers the process step by step.

Frequently asked questions

What is the OSHA hazard communication standard also known as?

OSHA's hazard communication standard (29 CFR 1910.1200) is also known as HazCom, the HazCom Standard, and the Right-to-Know Law. Safety professionals say "HazCom" most often in daily practice. Since 2012, it's also called GHS-aligned HazCom because OSHA revised it to match the UN's Globally Harmonized System for chemical classification and labeling. A 2024 update further refined physical hazard categories.

Is HazCom the same as the GHS?

No, they're related but different. GHS is the UN's Globally Harmonized System of Classification and Labelling of Chemicals, a voluntary international framework. HazCom (29 CFR 1910.1200) is the US legally enforceable OSHA standard. In 2012, OSHA revised HazCom to match GHS, adopting its 16-section SDS format and pictogram system. The GHS framework is the model; OSHA's HazCom standard is the law.

Does the hazard communication standard apply to construction?

Yes. Construction workers are covered under 29 CFR 1926.59, which incorporates the general industry HazCom standard at 29 CFR 1910.1200 by reference. The same five requirements apply: written program, chemical inventory, SDSs, container labels, and employee training. Construction employers also have to handle multi-employer worksites, where several contractors may expose each other's employees to hazardous chemicals.

What is the difference between an MSDS and an SDS?

An MSDS (Material Safety Data Sheet) was the old pre-2012 format. It had no required structure, so formats varied widely across suppliers. An SDS (Safety Data Sheet) is the current GHS-aligned format with exactly 16 sections in a fixed order. OSHA required the transition to SDSs to finish by June 2016. If you still have MSDSs in your binder, they're outdated and should be replaced with current SDSs from the supplier.

How many chemicals need to be on a HazCom chemical inventory?

Every hazardous chemical in your workplace has to be listed, with no minimum quantity threshold. A hazardous chemical is any chemical that presents a physical hazard or health hazard as defined in 29 CFR 1910.1200(c). In practice that includes most industrial cleaners, solvents, lubricants, adhesives, and paints. Consumer products used by employees in the same amounts a normal consumer would use are a narrow exception, but OSHA reads it strictly.

Can employees request a copy of an SDS?

Yes. Under 29 CFR 1910.1200(g)(9), employers must provide SDSs to employees and their designated representatives on request. Beyond that, SDSs have to be accessible during every work shift. That accessibility requirement means an electronic system has to be actually reachable from the work area, not locked behind a computer that's off-limits to floor workers. Keep a backup paper set for power outages or system failures.

What are the GHS pictograms and are employers required to train workers on them?

There are nine GHS pictograms: flame, flame over circle (oxidizers), gas cylinder, corrosion, exploding bomb, skull and crossbones, exclamation mark, environment (not OSHA-enforced), and health hazard (for carcinogens, sensitizers, and similar). Yes, training workers to recognize and interpret pictograms is explicitly required under 29 CFR 1910.1200(h)(3)(ii). Workers have to be able to explain what a pictogram means on a label they're likely to see.

How often does HazCom training need to be repeated?

The standard doesn't require annual retraining on a fixed schedule. Retraining is required when a new physical or health hazard enters the work area, or when job tasks change and expose workers to new chemicals. Most safety professionals run annual refreshers anyway because it's easy to document and catches gaps. Initial training for each new employee has to happen before they're exposed to hazardous chemicals, not at some vague point during orientation.

What is a secondary container and how must it be labeled?

A secondary container is any container a chemical has been transferred into from its original packaging, like a spray bottle filled from a jug of cleaner. Under HazCom, secondary containers must carry the chemical identity and hazard warnings. The standard allows simpler labeling for containers used immediately by the same employee who filled them, but that exception is narrow in practice. A label maker and a printed template are the low-cost fix for this frequent citation item.

Do small businesses with only a few employees have to follow HazCom?

Yes. HazCom has no small-business exemption based on headcount. Any employer covered by OSHA (private sector, one or more employees) with workers exposed to hazardous chemicals must comply with 29 CFR 1910.1200. The only size-related relief is that smaller employers often get lower penalty assessments after a citation. The requirements themselves still apply.

What does 'available to employees' mean for written HazCom programs?

Under 29 CFR 1910.1200(e)(4), the written hazard communication program must be available to employees, their designated representatives, OSHA, and NIOSH. In practice, employees need to know where the document is and be able to read it during work hours. Storing it only in a locked manager's office or buried in an HR system workers can't reach would likely fail an OSHA audit. A shared drive, a posted binder, or a safety board all work.

Is there a HazCom requirement for multi-employer worksites?

Yes. When employees of different employers share a workplace, employers must coordinate hazard information. Under 29 CFR 1910.1200(e)(2), employers who produce, use, or store hazardous chemicals at a multi-employer site must make sure the other employer's employees can access the SDSs and know the labeling system in use. This comes up constantly in construction, in manufacturing with contractors, and in building services.

How does HazCom interact with OSHA's lockout/tagout standard?

HazCom and lockout/tagout (29 CFR 1910.147) overlap when maintenance or servicing work involves hazardous chemicals. Workers doing LOTO on chemical processing equipment need both LOTO training and HazCom training covering the chemicals in that system. If a pipe holds a corrosive or toxic substance, SDSs need to be accessible to the maintenance crew, and labeling requirements still apply to that equipment. See the lockout tagout guide for the full LOTO requirements.

Sources

1. OSHA, 29 CFR 1910.1200 Hazard Communication Standard (current regulatory text): Formal requirements for written program, labels, SDSs, training, and the quote about program availability to employees and representatives
2. OSHA, Hazard Communication: Safety Data Sheets guidance page: GHS alignment in the 2012 revision, 16-section SDS format requirement, and GHS pictogram requirements
3. OSHA, HazCom 2024 Final Rule announcement and overview: 2024 final rule updates to flammable gases, aerosols, and physical hazard criteria with phased compliance deadlines
4. OSHA, 29 CFR 1926.59 Hazard Communication (Construction): Construction industry HazCom requirements incorporating 1910.1200 by reference
5. OSHA, Hazard Communication Final Rule Regulatory Impact Analysis (2012): 43 million workers across 5 million workplaces covered; projected 585 fatalities prevented and $2.4 billion in benefits annually
6. OSHA, State Plans program page: 29 OSHA-approved State Plans exist as of 2024; states must have standards at least as effective as federal OSHA
7. United Nations, GHS Purple Book (Globally Harmonized System of Classification and Labelling of Chemicals): GHS framework origin, structure, and the 9th revised edition referenced in OSHA's 2024 HazCom update
8. OSHA, Top 10 Most Cited Standards FY2023: HazCom (29 CFR 1910.1200) consistently appears in OSHA's annual top-10 most cited standards list
9. OSHA, Civil Penalty Amounts (2024 annual inflation adjustment): FY2024 maximum penalties: $16,131 per serious violation, $161,323 for willful or repeated violations
10. OSHA, 29 CFR 1910.1000 Air Contaminants (Table Z-1 PELs): OSHA Permissible Exposure Limits are legally enforceable and must be listed in SDS Section 8
11. ACGIH (American Conference of Governmental Industrial Hygienists), TLV and BEI Documentation: ACGIH TLVs are published annually based on current health science and are not legally enforceable by OSHA except through the General Duty Clause
12. OSHA, Hazard Communication Enforcement and Common Violations: Most common HazCom violations include no written program, missing SDSs, improper container labeling, and insufficient training