OSHA Safety Certification / OSHA 10 / OSHA 30: Hazard Communication (29 CFR 1910.1200)

Hazard Communication Standard (HazCom / GHS) — SDS, Labels, Pictograms, Routes of Entry

Audience: working professional / trade certification candidate

OSHA's Hazard Communication Standard (HCS), aligned with the Global Harmonization System (GHS), gives workers the legal right to know about chemical hazards through a written HAZCOM program, Safety Data Sheets, GHS-compliant labels, and training — all of which are the employer's responsibility to provide.

Key Points

• The 'Right to Know' law is officially called the Hazard Communication Standard (HCS), 29 CFR 1910.1200.
• Four routes of chemical entry: inhalation, ingestion, absorption, injection.
• Acute exposure = short-term, immediate effects. Chronic exposure = prolonged/repeated, delayed effects.
• Written HAZCOM program required: chemical list + SDS for each + label on each container + training plan.
• SDS must be fully accessible to workers at all times during the workshift — not locked in an office.
• GHS label requires 6 elements: product identifier, signal word, hazard statements, precautionary statements, pictograms, supplier information.
• Two signal words: DANGER (more severe hazard) and WARNING (less severe hazard) — never both on one label.
• 9 total GHS pictograms; 8 are OSHA-required (environmental pictogram is not mandatory).
• SDS has 16 uniform sections — OSHA does not enforce Sections 12, 14, or 15 (other agencies regulate).
• Training required: before first assignment AND whenever a new physical or health hazard is introduced.
• Manufacturers/importers/distributors must provide labels and SDS; employers must maintain and make accessible.
• SDS must be printed in English; other languages may be provided additionally.

Why It Matters: HazCom is consistently among OSHA's top 5 most-cited standards. Exam writers use SDS section identification scenarios and label element questions because workers regularly encounter chemical hazards without knowing where to look for protection information. In the field, a worker who can't find or read an SDS in an emergency faces a preventable injury.

Terms To Remember

HCS (Hazard Communication Standard)

OSHA's 'Right to Know' law — 29 CFR 1910.1200; requires chemical hazard info to be communicated to workers.

GHS (Globally Harmonized System)

International standard for classifying and labeling chemicals; HCS aligns with GHS for consistency.

HAZCOM Program

Employer's written program covering chemical list, SDS, labels, and training.

SDS (Safety Data Sheet)

16-section standardized document describing chemical hazards, handling, storage, emergency response, and PPE.

Routes of Entry

Ways chemicals enter the body: inhalation, ingestion, absorption, injection.

Inhalation

Chemical enters through airways when breathed in — most common route of workplace exposure.

Ingestion

Chemical enters through mouth — direct contact or hand-to-mouth transfer.

Absorption

Chemical enters through skin or eyes — contact without ingestion or inhalation.

Injection

Chemical enters through puncture wound from needle or sharp object contaminated with hazardous material.

Acute Exposure

Short-term/brief exposure with immediate health effects (e.g., skin rash from chemical contact).

Chronic Exposure

Repeated or prolonged exposure over months/years with delayed, permanent effects (e.g., cancer from asbestos).

Physical Hazard

Chemical property that creates fire, explosion, or dangerous reaction risk.

Health Hazard

Chemical that causes acute or chronic health effects through exposure.

Signal Word

DANGER or WARNING on GHS label — indicates relative severity; never both on same label.

Pictogram

GHS symbol in red diamond border conveying hazard category; 9 total, 8 OSHA-required.

Hazard Statement

Standardized phrase describing nature and degree of hazard (e.g., 'Causes serious eye damage').

Precautionary Statement

Measures to minimize or prevent adverse effects from hazard (e.g., 'Wear protective gloves').

Product Identifier

Chemical name, code, or batch number that matches the SDS.

Secondary Container

Any container other than the original shipping container; must also be labeled.

Step Process Formula

Title: Two Core Skills: Identifying the Correct SDS Section by Scenario + Reading a GHS Label — Side-by-Side

Routes Of Entry And Exposure Types

Title: Routes of Entry & Exposure Types

Routes

Route: Inhalation

Mechanism: Breathing chemicals into airways (lungs)

Example: Spray painting in unventilated space; solvent vapors

Prevention: Respiratory PPE, ventilation, engineering controls

Route: Ingestion

Mechanism: Swallowing chemicals directly or via hand-to-mouth contact

Example: Eating or drinking near chemicals; touching face with contaminated gloves

Prevention: Hand washing, no eating/drinking in chemical areas, gloves

Route: Absorption

Mechanism: Chemical penetrates through skin or eyes

Example: Sodium hydroxide spill on arm; solvent soaks through gloves

Prevention: Chemical-resistant gloves, safety glasses, full-coverage clothing

Route: Injection

Mechanism: Penetration through puncture wound from sharp contaminated object

Example: Needle stick; high-pressure injection from spray gun

Prevention: Puncture-resistant gloves, sharps containers, safe handling procedures

Exposure Types

Acute

Definition: Short-term or brief exposure with immediate, obvious health effects.

Example: Skin rash from brief contact with chemical irritant; eye burning from splash.

Key Characteristic: Immediate — symptoms appear quickly after exposure.

Chronic

Definition: Repeated or prolonged exposure over months or years with slowly developing, often permanent effects.

Example: Cancer from long-term asbestos exposure; liver damage from repeated solvent exposure.

Key Characteristic: Delayed — person may not see, feel, or smell the danger; effects may be permanent.

Part A SDS Sections

Label: Part A — SDS 16-Section Format: Identifying the Correct Section by Scenario

Format Rule: OSHA requires a UNIFORM 16-section format. Section numbers and headings are standardized — every SDS looks the same regardless of manufacturer.

Unenforced Sections: OSHA does not enforce Sections 12 (Ecological Information), 14 (Transport Information), or 15 (Regulatory Information) — other agencies regulate these.

All 16 Sections

Identification

Section: 1

Contains: Product identifier, manufacturer name, address, phone number, emergency contact, recommended use, restrictions.

Use When: Need manufacturer contact info; need to verify product identity; check emergency phone number.

Hazard Identification

Section: 2

Contains: GHS classification, signal word, hazard statements, precautionary statements, pictograms, unknown hazards.

Use When: Need to understand what hazards the chemical presents; verify label information.

Composition / Information on Ingredients

Section: 3

Contains: Chemical name(s), CAS numbers, concentration ranges, trade secrets.

Use When: Need to know exact chemical components or CAS numbers for exposure assessment.

First-Aid Measures

Section: 4

Contains: Emergency first aid by route of exposure (inhalation, skin, eyes, ingestion); symptoms; notes to physician.

Use When: EMERGENCY — worker has been exposed and needs immediate first aid guidance.

Fire-Fighting Measures

Section: 5

Contains: Suitable extinguishing media, specific hazards during fire, special PPE for firefighters.

Use When: Chemical is on fire or near fire; selecting correct extinguisher type.

Accidental Release Measures

Section: 6

Contains: Personal precautions, PPE, environmental precautions, cleanup methods for spills and leaks.

Use When: Chemical has been spilled or released; need cleanup and containment procedures.

Handling and Storage

Section: 7

Contains: Safe handling precautions, storage conditions (temperature, humidity, incompatible materials), container requirements.

Use When: Setting up storage; transferring chemical to secondary container; determining compatible storage.

Exposure Controls / Personal Protection

Section: 8

Contains: OSHA PELs, ACGIH TLVs, engineering controls, administrative controls, required PPE (gloves, respirator, eye protection).

Use When: Selecting PPE; verifying exposure limits; designing ventilation controls.

Physical and Chemical Properties

Section: 9

Contains: Appearance, odor, pH, boiling point, flash point, flammability, vapor pressure, density, solubility.

Use When: Assessing fire risk (flash point); understanding vapor behavior; identifying unknown substance.

Stability and Reactivity

Section: 10

Contains: Chemical stability, conditions to avoid, incompatible materials, hazardous decomposition products.

Use When: Assessing compatibility with other chemicals; identifying dangerous reaction conditions.

Toxicological Information

Section: 11

Contains: Routes of exposure, symptoms of exposure, acute and chronic health effects, carcinogenicity, LD50/LC50.

Use When: Determining routes of exposure and symptoms; assessing long-term health risks; investigating exposure incident.

Ecological Information

Section: 12

Contains: Environmental fate, aquatic toxicity, persistence, bioaccumulation. NOT enforced by OSHA.

Use When: Environmental impact assessment (EPA jurisdiction).

Disposal Considerations

Section: 13

Contains: Waste disposal methods, regulatory requirements for disposal.

Use When: Disposing of chemical waste; determining disposal classification.

Transport Information

Section: 14

Contains: DOT, IATA, IMDG shipping classifications. NOT enforced by OSHA.

Use When: Shipping or transporting chemicals (DOT jurisdiction).

Regulatory Information

Section: 15

Contains: OSHA, EPA, state regulations beyond HCS. NOT enforced by OSHA.

Use When: Compliance review for other regulatory programs.

Other Information

Section: 16

Contains: Date of preparation or last revision, changes from previous version, disclaimer.

Use When: Verifying SDS is current; checking when information was last updated.

Scenario Lookup Table

Worker exposed to chemical — need immediate first aid

Correct Section: Section 4 — First-Aid Measures

Need manufacturer's phone number

Correct Section: Section 1 — Identification

Determining correct storage location and conditions

Correct Section: Section 7 — Handling and Storage

Chemical spilled on floor — need cleanup procedure

Correct Section: Section 6 — Accidental Release Measures

Routes of exposure and symptoms of exposure

Correct Section: Section 11 — Toxicological Information

Selecting correct fire extinguisher

Correct Section: Section 5 — Fire-Fighting Measures

What PPE is required for this chemical?

Correct Section: Section 8 — Exposure Controls / Personal Protection

Is this chemical compatible with sulfuric acid?

Correct Section: Section 10 — Stability and Reactivity

Chemical has a strong odor — is it flammable?

Correct Section: Section 9 — Physical and Chemical Properties (flash point)

Long-term cancer risk from this chemical?

Correct Section: Section 11 — Toxicological Information (carcinogenicity)

How to dispose of leftover chemical waste?

Correct Section: Section 13 — Disposal Considerations

When was the SDS last updated?

Correct Section: Section 16 — Other Information

Part B GHS Label

Label: Part B — Reading a GHS Label & Identifying Hazard Class

Required Label Elements

Title: 6 Required GHS Label Elements (Plus Supplier Information)

Elements

Element: 1. Product Identifier

Description: Chemical name, code number, or batch number that links the container to its SDS.

Element: 2. Signal Word

Description: DANGER (severe hazard) or WARNING (less severe hazard). Never both on the same label.

Element: 3. Hazard Statements

Description: Standardized phrases describing the nature and degree of hazard (e.g., 'Fatal if inhaled').

Element: 4. Precautionary Statements

Description: Recommended measures to minimize or prevent adverse effects (e.g., 'Use only outdoors or in well-ventilated area').

Element: 5. Pictograms

Description: GHS hazard symbols in red diamond borders — one or more may appear based on chemical hazards.

Element: 6. Supplier Information

Description: Manufacturer/importer/distributor name, address, and telephone number.

Signal Word Rule: DANGER = more severe hazard category. WARNING = less severe. A single label uses ONLY ONE signal word — always the more severe one if multiple hazards exist.

All 9 Pictograms

Title: All 9 GHS Pictograms — Hazards Represented

OSHA Required: 8

Not Required: Environmental (Aquatic Toxicity) — environmental hazards outside OSHA jurisdiction

Pictograms

Name: Health Hazard (Silhouette with starburst)

OSHA Required: True

Hazards

• Carcinogen
• Mutagenicity
• Reproductive Toxicity
• Respiratory Sensitizer
• Target Organ Toxicity
• Aspiration Toxicity

Name: Flame

OSHA Required: True

Hazards

• Flammables
• Pyrophorics
• Self-Heating
• Emits Flammable Gas
• Self-Reactives
• Organic Peroxides

Name: Exploding Bomb

OSHA Required: True

Hazards

• Explosives
• Self-Reactives
• Organic Peroxides

Name: Flame Over Circle

OSHA Required: True

Hazards

• Oxidizers — substances that intensify burning of other materials

Name: Gas Cylinder

OSHA Required: True

Hazards

• Gases Under Pressure — compressed, liquefied, dissolved, or refrigerated liquefied gases

Name: Corrosion (test tube with damage to surface and hand)

OSHA Required: True

Hazards

• Skin Corrosion/Burns
• Eye Damage
• Corrosive to Metals

Name: Skull and Crossbones

OSHA Required: True

Hazards

• Acute Toxicity — Fatal or toxic if swallowed, inhaled, or in skin contact (severe categories)

Name: Exclamation Mark

OSHA Required: True

Hazards

• Irritant (skin and eye)
• Skin Sensitizer
• Acute Toxicity (harmful — less severe than skull)
• Narcotic Effects
• Respiratory Tract Irritant
• Hazardous to Ozone Layer (non-mandatory)

Name: Environment (fish and tree)

OSHA Required: False

Hazards

• Aquatic Toxicity — chronic and acute hazards to aquatic environment

Note: NOT required by OSHA — environmental hazards regulated by EPA.

Key Distinction: Skull and Crossbones = FATAL/TOXIC (severe acute toxicity). Exclamation Mark = HARMFUL/IRRITANT (less severe acute toxicity). Both involve acute toxicity — severity level distinguishes them.

Label Reading Scenarios

A container shows a Flame pictogram and signal word DANGER. What does this indicate?

Answer: The chemical is a flammable, pyrophoric, self-heating, or similar fire hazard in a severe category. DANGER indicates the more severe hazard category for that classification.

A label shows both a Skull and Crossbones and an Exclamation Mark. Is this possible?

Answer: Yes — they represent different hazard categories. Skull and Crossbones indicates severe acute toxicity (fatal); Exclamation Mark indicates a different, less severe hazard (irritant, skin sensitizer). Multiple pictograms are common on complex chemicals.

A label shows only a Gas Cylinder pictogram with signal word WARNING. What is the primary hazard?

Answer: Gases under pressure — could explode if heated, asphyxiate in confined spaces, or cause cold burns if liquefied. WARNING indicates a less severe pressure gas category.

Howard spills sodium hydroxide on his arm — which pictogram would appear on the label?

Answer: Corrosion pictogram — sodium hydroxide causes skin corrosion/burns and eye damage. Route of entry = absorption (through skin).

Employer Hazcom Requirements

Title: Employer HAZCOM Program Requirements & Training Rules

Written Program Must Include

• A list of ALL hazardous chemicals known to be in the workplace.
• A Safety Data Sheet (SDS) for each hazardous chemical — updated when new information is available.
• A warning label on EACH container of hazardous chemical — cannot be defaced or removed.
• A training plan to communicate hazard information to employees.

SDS Accessibility Rule

Requirement: SDS must be FULLY ACCESSIBLE and AVAILABLE to employees during the entire workshift.

Compliant Examples: Binder in work area, electronic terminal accessible on the floor, posted in chemical storage room.

Non Compliant Examples: Locked in supervisor's office, on a computer only the manager can access, stored off-site.

Key Exam Trap: SDSs on a computer in the supervisor's office = NOT compliant — workers must be able to access them without requesting permission or assistance.

Training Requirements

When Required

• Before starting an assignment for the first time in an area with hazardous chemicals.
• Whenever a new physical or health hazard is introduced into the work area.
• When transitioning to a new work area with different chemical hazards.
• When workplace operations or chemical inventory changes significantly.

Training Must Cover

• Requirements of the Right-to-Know law (HCS).
• Details and location of the written HAZCOM plan.
• Instructions for working safely around hazardous chemicals.
• List of hazardous chemicals in the workplace.
• Location, availability, and explanation of SDSs.
• Physical and health hazard information for chemicals in the work area.
• Methods to detect presence or release of chemicals (monitoring equipment, visual, odor).
• Specific procedures for personal protection (PPE requirements).

Who Trains: Employer's responsibility to develop, implement, and maintain — cannot be delegated away.

Ongoing Nature: HAZCOM training is an ongoing process — not a one-time event.

Manufacturer Distributor Requirements

Must Provide: Warning label on container AND applicable SDS prior to or at time of shipment.

SDS Requirements

• Completely legible.
• Updated when new information is available.
• Printed in English (other languages may be provided additionally).
• Uniform 16-section format.

Cannot Ship Without: Label and SDS — both required before chemical can legally be shipped.

Four Party Responsibility Summary

Party: Chemical Manufacturers

Responsibility: Classify chemicals; prepare SDS; apply GHS-compliant labels on shipped containers.

Party: Importers

Responsibility: Same as manufacturers for imported chemicals.

Party: Distributors

Responsibility: Ensure containers remain labeled; provide SDS with shipments.

Party: Employers

Responsibility: Maintain written HAZCOM program; keep SDS accessible; ensure containers stay labeled; train workers.

Common Confusions

• Students confuse SDS with the container label because both communicate chemical hazards — the SDS is a detailed 16-section document stored in the workplace (not on the container); the label is physically attached to the container and must always remain on it; the label provides quick hazard ID while the SDS provides complete detailed information.
• Students confuse Skull and Crossbones with Exclamation Mark because both relate to acute toxicity — Skull and Crossbones indicates FATAL or TOXIC at severe categories (Category 1–3); Exclamation Mark indicates HARMFUL, IRRITANT, or SENSITIZER at less severe categories (Category 4–5); severity level is the distinction.
• Students confuse acute exposure with chronic exposure because both describe harmful chemical contact — acute exposure is short-term with IMMEDIATE effects (rash within hours); chronic exposure is long-term/repeated with DELAYED effects that may take years to appear (cancer from asbestos); chronic effects may be permanent and the worker may not know they're being harmed.
• Students confuse the SDS section for routes of exposure vs. first aid because both relate to exposure — Section 11 (Toxicological Information) describes routes of exposure and symptoms; Section 4 (First-Aid Measures) describes what to DO after exposure by route; in an emergency go to Section 4; to understand hazards before working, use Section 11.

Quick Questions

A worker walks into a bathroom and smells a strong chemical odor from a recent cleaning. Which SDS section should they consult to determine routes of exposure and symptoms?

Correct Answer: Section 11 — Toxicological Information. This section describes routes of exposure (inhalation, skin, eyes, ingestion), symptoms of exposure, and acute/chronic health effects. If the worker was already exposed and needs immediate first aid, they would go to Section 4 instead.

A container of cleaning solution shows a Corrosion pictogram and the signal word DANGER with the hazard statement 'Causes severe skin burns and eye damage.' A worker spills it on their forearm through their clothing. What is the route of entry?

Correct Answer: Absorption — the chemical penetrated through the skin. The Corrosion pictogram confirms skin corrosion/burns and eye damage hazards. The appropriate first aid response is in Section 4 of the SDS; PPE requirements (chemical-resistant gloves and eye protection) are in Section 8.

An employer tells a new worker that all SDSs are stored on a computer in the manager's office and accessible upon request. Does this comply with OSHA's HazCom Standard?

Correct Answer: No — this does not comply. OSHA requires SDSs to be fully accessible and available to workers during their entire workshift without having to request access through a supervisor. The worker must be able to access the SDS independently at any time. Acceptable options include a binder in the work area, a computer terminal accessible on the production floor, or SDSs posted in the chemical storage area.

Exam Answer Frame

Style: 5-mark

Question: A manufacturing company is setting up a new work area that will use three hazardous cleaning solvents. Describe the employer's minimum obligations under OSHA's Hazard Communication Standard before workers begin using these chemicals.

Model Answer: Under 29 CFR 1910.1200 (HCS/HazCom), the employer must: (1) Update the written HAZCOM program to include the three new solvents on the workplace chemical list. (2) Obtain and maintain an SDS for each solvent — each SDS must be completely legible, printed in English, current, and in the uniform 16-section format. SDSs must be fully accessible to workers in the work area at all times during the workshift — not locked away or requiring supervisor access. (3) Ensure each solvent container has a GHS-compliant label with all six required elements: product identifier, signal word (DANGER or WARNING), hazard statements, precautionary statements, pictograms, and supplier information. Labels must not be defaced or removed. (4) Train all workers who will work in the new area BEFORE they begin their first assignment there. Training must cover: the chemicals present, physical and health hazards of each solvent, routes of entry, how to read the SDS and label, detection methods, and specific PPE required. (5) If any worker is moved from another area into this new area, they must also receive training on the new chemical hazards before starting work in that area — even if they previously completed general HAZCOM training. The employer bears responsibility for all of these obligations — they cannot be transferred to the worker.