Glossary

Plain-language definitions for every term you will encounter. Browse by letter or filter by category.

OSHA Standards30Hazard Types86Safety Equipment64Training40Compliance44Emergency Response17

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2

5

A

Abatement

The corrective action an employer must take to fix a cited hazard within the timeframe OSHA specifies.

Compliance

Atmospheric Testing

Monitoring air quality in confined spaces to detect oxygen deficiency, combustible gases, and toxic substances.

Hazard Types

Anchor Point

A secure attachment point capable of supporting 5,000 pounds per worker connected for fall arrest systems.

Safety Equipment

Arc Flash

A dangerous release of energy caused by an electrical fault that produces intense heat, light, and pressure.

Hazard Types

Assembly Point

A designated safe location outside a building where employees gather after evacuating during an emergency.

Emergency Response

AED

Automated External Defibrillator, a portable device that delivers an electric shock to restore heart rhythm.

Emergency Response

Attendant

A trained person stationed outside a confined space to monitor entrants and summon rescue if needed.

Training

Administrative Controls

Work practices, policies, and procedures that reduce hazard exposure through changes in how work is performed.

Training

Audiometric Testing

Annual hearing tests required for workers exposed to noise at or above OSHA's 85 decibel action level.

Hazard Types

Asbestos

A naturally occurring mineral fiber that causes cancer and lung disease when its fibers become airborne and inhaled.

Hazard Types

ANSI

American National Standards Institute, the organization that coordinates voluntary safety and quality standards.

Compliance

ANSI Z87.1

The standard for occupational and educational eye and face protection specifying impact and coverage requirements.

Compliance

ANSI Z89.1

The standard for industrial head protection specifying impact resistance and electrical insulation requirements.

Compliance

ACGIH

American Conference of Governmental Industrial Hygienists, the organization publishing TLV exposure guidelines.

Compliance

Authorized Person

A worker trained and authorized to perform lockout/tagout and service or maintain machines and equipment.

Training

Affected Person

A worker whose job requires operating equipment that is under lockout/tagout by an authorized person.

Training

Aerial Lift

A vehicle-mounted platform such as a cherry picker or boom lift used to elevate workers to height.

Safety Equipment

Arc Flash Boundary

The distance from energized equipment at which an arc flash could cause a second-degree burn.

Hazard Types

ALARA

As Low As Reasonably Achievable, the principle of minimizing radiation exposure through practical measures.

Hazard Types

Area Monitoring

Placing sampling devices in fixed locations to measure general ambient levels of airborne contaminants.

Safety Equipment

Accident Investigation

A structured process to determine what happened, why it happened, and how to prevent similar incidents.

Training

Annual Training

Safety training conducted once per year to maintain compliance with OSHA standards requiring periodic retraining.

Training

B

C

Citation

A formal notice issued by OSHA to an employer documenting a specific safety violation found during inspection.

Compliance

Confined Space

An enclosed area with limited entry and exit that is not designed for continuous occupancy by workers.

Hazard Types

Competent Person

A worker capable of identifying hazards and authorized to take prompt corrective measures to eliminate them.

Training

CPR

Cardiopulmonary Resuscitation, an emergency procedure combining chest compressions and rescue breathing.

Emergency Response

Crane Safety

Procedures and standards for safe crane operation including load calculations, rigging, and signal communication.

Safety Equipment

Cave-In

The collapse of soil or rock walls in an excavation, one of the leading causes of construction fatalities.

Hazard Types

Corrective Action

Steps taken to eliminate the cause of a detected nonconformity or hazard and prevent its recurrence.

Compliance

Cold Stress

Health effects from working in cold environments including frostbite, hypothermia, and trench foot.

Hazard Types

Combustible Dust

Fine particles that can ignite and explode when dispersed in air, such as grain dust, wood dust, or metal powder.

Hazard Types

Caught-In Hazard

A danger where a worker's body or clothing is caught in, between, or compressed by machinery or objects.

Hazard Types

Controlling Employer

The employer with general supervisory authority over a worksite, responsible for correcting hazards or requiring others to.

OSHA Standards

Combustible Gas

A gas or vapor that can ignite and burn when mixed with air in concentrations between its LEL and UEL.

Hazard Types

Compressed Gas

Gas stored under pressure in cylinders that poses explosion, asphyxiation, or toxicity risks if mishandled.

Hazard Types

Cylinder Storage

Proper storage of compressed gas cylinders upright, secured, capped, and separated by gas compatibility.

Safety Equipment

Chemical Resistant Gloves

Gloves made from materials like nitrile, neoprene, or butyl rubber that resist permeation by specific chemicals.

Safety Equipment

Cut Resistant Gloves

Gloves rated by ANSI cut levels that protect hands from sharp edges, blades, and abrasive materials.

Safety Equipment

Chemical Hygiene Plan

A written plan for laboratories describing procedures to protect employees from health hazards of chemicals.

Compliance

Confined Space Rescue

Procedures and trained teams prepared to extract workers from confined spaces during emergencies.

Emergency Response

Continuous Air Monitoring

Ongoing real-time measurement of atmospheric conditions inside a confined space during the entire entry period.

Safety Equipment

Carbon Monoxide

An odorless, colorless toxic gas produced by incomplete combustion that can cause death at high concentrations.

Hazard Types

Cadmium

A toxic heavy metal found in batteries and coatings that causes kidney damage and lung cancer when inhaled.

Hazard Types

Closing Conference

The meeting at the end of an OSHA inspection where the compliance officer discusses findings and potential citations.

OSHA Standards

Creating Employer

The employer whose workers create a hazard that exposes employees of other employers on a multi-employer site.

OSHA Standards

Compliance Officer

An OSHA inspector authorized to conduct workplace inspections and issue citations for safety violations.

OSHA Standards

Confined Space Program

A written program establishing procedures, training, and equipment requirements for safe confined space entry.

Compliance

D

E

EMR

Experience Modification Rate comparing an employer's workers comp claims to the industry average for premium pricing.

Compliance

Ergonomics

The science of designing workstations and tasks to fit the worker and reduce musculoskeletal injury risk.

Hazard Types

Electrical Safety

Practices and standards designed to protect workers from electrical shock, arc flash, and electrocution hazards.

Hazard Types

Emergency Action Plan

A written document describing procedures employees must follow during workplace emergencies such as fires or spills.

Emergency Response

Evacuation Plan

A documented plan showing exit routes, assembly points, and procedures for safely leaving a building in an emergency.

Emergency Response

Exposure Control Plan

A written plan identifying tasks with bloodborne pathogen exposure risk and the controls to minimize that risk.

Compliance

Excavation

Any man-made cut, cavity, trench, or depression in the earth formed by removing soil or rock.

Hazard Types

Entry Permit

A written authorization documenting hazards, controls, and personnel for safe entry into a permit-required space.

Compliance

Entry Supervisor

The person responsible for authorizing confined space entry and ensuring all safety procedures are followed.

Training

Eye Wash Station

A fixed or portable device providing a gentle stream of water to flush hazardous substances from the eyes.

Emergency Response

Emergency Shower

A plumbed fixture that delivers a large volume of water to rinse chemical contaminants off a worker's body.

Emergency Response

Engineering Controls

Physical changes to the workplace or equipment that isolate workers from hazards without relying on behavior.

Hazard Types

Energy Isolation

The process of disconnecting machinery from all energy sources including electrical, hydraulic, and pneumatic.

Hazard Types

Electrical PPE

Insulated gloves, sleeves, and mats rated for specific voltage levels to protect against electrical contact.

Safety Equipment

Energized Work

Work performed on electrical equipment that has not been de-energized, requiring special training and PPE.

Hazard Types

Explosion Proof Equipment

Electrical devices designed to contain internal explosions and prevent ignition of surrounding atmospheres.

Safety Equipment

Exposure Assessment

Measuring or estimating the intensity, frequency, and duration of worker contact with workplace hazards.

Compliance

Exposing Employer

An employer whose workers are exposed to a hazard created or controlled by another employer on the same site.

OSHA Standards

Electrical Lockout

Applying a lock to an electrical disconnect switch to prevent accidental re-energization during maintenance.

Hazard Types

F

Fit Test

A procedure verifying that a respirator forms an adequate seal on the wearer's face before workplace use.

Safety Equipment

Fall Protection

Systems and equipment designed to prevent or arrest falls from elevation, required at heights of six feet or more.

Safety Equipment

Fire Extinguisher

A portable device used to suppress small fires, classified by the type of fire it is designed to combat.

Emergency Response

Fire Class

A classification system categorizing fires by fuel type: A for ordinary, B for flammable liquid, C for electrical.

Emergency Response

Fire Prevention

Measures taken to reduce fire risk including proper storage, housekeeping, and elimination of ignition sources.

Emergency Response

First Aid

Immediate medical care provided to an injured or ill person before professional emergency responders arrive.

Emergency Response

First Aid Kit

A collection of medical supplies and equipment kept readily available for treating minor workplace injuries.

Emergency Response

Forklift

A powered industrial truck used to lift and move materials, requiring operator training and certification.

Safety Equipment

Fire Watch

A designated person who monitors for fire during and after hot work, ready to extinguish incipient fires.

Emergency Response

Face Shield

A transparent protective device covering the entire face to guard against splashes, flying particles, and heat.

Safety Equipment

Frostbite

Freezing of skin and underlying tissue caused by exposure to extremely cold temperatures or wind chill.

Hazard Types

Focus Four Hazards

The four leading causes of construction fatalities: falls, struck-by, caught-in/between, and electrocution.

OSHA Standards

Floor Opening

An opening in a floor or platform measuring 12 inches or more that must be guarded to prevent falls.

Hazard Types

Flammable Liquid

A liquid with a flash point below 100 degrees Fahrenheit that can easily ignite from sparks or open flames.

Hazard Types

Flash Point

The lowest temperature at which a liquid gives off enough vapor to form an ignitable mixture with air.

Hazard Types

Flammable Storage Cabinet

A fire-rated cabinet designed to safely store flammable and combustible liquids and limit fire spread.

Safety Equipment

Full-Face Respirator

A reusable respirator covering the entire face, providing both respiratory and eye protection from contaminants.

Safety Equipment

Fall Arrest System

A system that stops a worker who is already falling, consisting of an anchor, connector, and body harness.

Safety Equipment

Fall Restraint System

A system that prevents a worker from reaching a fall hazard edge, rather than arresting a fall in progress.

Safety Equipment

Fit for Duty

A determination that a worker is physically and mentally capable of performing job duties safely.

Compliance

Four Gas Monitor

A portable device that simultaneously detects oxygen, LEL, carbon monoxide, and hydrogen sulfide levels.

Safety Equipment

Formaldehyde

A chemical used in manufacturing that is a known carcinogen, with an OSHA PEL of 0.75 ppm TWA.

Hazard Types

Fall Distance

The vertical distance a worker would travel during a fall before a fall arrest system stops the descent.

Hazard Types

G

H

Hard Hat

Head protection worn to guard against impact from falling objects and electrical contact in the workplace.

Safety Equipment

Hearing Protection

Earplugs or earmuffs worn to reduce noise exposure and prevent occupational hearing loss in loud environments.

Safety Equipment

Harness

A full-body fall arrest device that distributes fall forces across the torso, thighs, and shoulders of the wearer.

Safety Equipment

HazCom

Hazard Communication Standard requiring employers to inform workers about chemical hazards through labels and SDS.

OSHA Standards

Hot Work

Operations producing heat, sparks, or flame such as welding, cutting, or brazing that could ignite nearby materials.

Hazard Types

Hot Work Permit

A written authorization required before performing welding, cutting, or other spark-producing work in hazardous areas.

Compliance

High Visibility Clothing

Fluorescent and reflective garments worn to make workers visible in areas with vehicle or equipment traffic.

Safety Equipment

HazMat

Hazardous Materials that pose a risk to health, safety, or the environment during storage, use, or transport.

Hazard Types

Hierarchy of Controls

A ranked system for reducing hazards: elimination, substitution, engineering, administrative, then PPE.

Training

HAZOP

Hazard and Operability Study, a structured method to identify process deviations and their potential consequences.

Compliance

Hearing Conservation

An OSHA program requiring monitoring, audiometric testing, and protection for workers exposed to high noise.

Compliance

Heat Stress

A condition caused by excessive heat exposure that can lead to heat exhaustion, heat stroke, or death.

Hazard Types

Heat Illness Prevention

A program providing water, rest, shade, and acclimatization to protect workers from heat-related illness.

Training

Hypothermia

A dangerous drop in body temperature below 95 degrees Fahrenheit caused by prolonged cold exposure.

Hazard Types

Housekeeping

Maintaining a clean and orderly workplace to prevent slips, trips, falls, and accumulation of hazardous materials.

Training

Hazard Statement

A standardized phrase on a GHS label describing the nature and degree of a chemical's hazard.

Hazard Types

Hazard Assessment

A workplace evaluation to identify hazards and determine the appropriate PPE and controls for each task.

Training

Half-Face Respirator

A reusable respirator covering the nose and mouth that uses replaceable cartridges to filter air contaminants.

Safety Equipment

Horizontal Lifeline

A cable or strap stretched between two anchor points allowing workers to move laterally while remaining tied off.

Safety Equipment

Hazardous Location

An area classified by NEC where flammable gases, vapors, or combustible dusts may be present.

Hazard Types

Hydrogen Sulfide

A toxic gas with a rotten egg odor found in sewers and oil fields that paralyzes the sense of smell at high levels.

Hazard Types

Hexavalent Chromium

A toxic form of chromium generated during welding or painting that causes lung cancer when inhaled.

Hazard Types

Hazard Communication Program

A written workplace plan for informing employees about chemical hazards through labels, SDS, and training.

Compliance

I

J

L

Lost Time Injury

A workplace injury that results in the employee missing one or more scheduled workdays beyond the day of injury.

OSHA Standards

LOTO

Lockout/Tagout procedures prevent accidental machine startup during maintenance by isolating energy sources.

Hazard Types

Lockout Tagout

A safety procedure using locks and tags to ensure hazardous machines are properly shut off during servicing.

Hazard Types

LEL

Lower Explosive Limit, the minimum concentration of a gas or vapor in air that can ignite and cause an explosion.

Hazard Types

Lanyard

A flexible connector linking a worker's harness to an anchor point or lifeline for fall arrest protection.

Safety Equipment

Ladder Safety

Practices for safe ladder use including proper setup angle, three points of contact, and weight rating compliance.

Safety Equipment

Lead Exposure

Contact with lead dust or fumes during activities such as painting, demolition, or battery manufacturing.

Hazard Types

Local Exhaust Ventilation

A system that captures contaminants at their source before they disperse into the general work area.

Safety Equipment

Lockout Device

A keyed lock placed on an energy-isolating device to keep equipment in a safe, de-energized state.

Safety Equipment

Lean Safety

Integrating lean manufacturing principles with safety management to eliminate waste and reduce injury risk.

Training

Leading Indicator

A proactive safety metric that measures prevention activities before injuries occur, such as inspections completed.

Compliance

Lagging Indicator

A reactive safety metric that measures outcomes after they occur, such as injury rates and lost workdays.

Compliance

M

N

O

P

Penalty

A monetary fine assessed by OSHA for workplace safety violations, adjusted annually for inflation.

Compliance

PPE

Personal Protective Equipment worn by workers to reduce exposure to hazards when engineering controls are not feasible.

Safety Equipment

PEL

Permissible Exposure Limit, the maximum concentration of a substance a worker may be exposed to per OSHA rules.

Hazard Types

Point of Operation

The area of a machine where work is performed on material, such as cutting, shaping, or forming.

Hazard Types

PIT Operator

A Powered Industrial Truck operator who has completed OSHA-required training and hands-on evaluation.

Training

Permit-Required Confined Space

A confined space containing hazards serious enough to require a written entry permit before workers may enter.

Hazard Types

Process Safety Management

An OSHA standard requiring management of highly hazardous chemicals through 14 elements including process reviews.

Compliance

PSM

Process Safety Management, the OSHA regulation for preventing catastrophic releases of highly hazardous chemicals.

Compliance

PHA

Process Hazard Analysis, a systematic review identifying and evaluating hazards in chemical processes.

Compliance

Pictogram

A standardized GHS symbol on chemical labels that visually communicates specific hazard types to workers.

Hazard Types

Precautionary Statement

A phrase on a GHS label recommending measures to minimize or prevent adverse effects from chemical exposure.

Hazard Types

Permit to Work

A formal written system controlling high-risk activities by requiring documented authorization before work begins.

Compliance

Pedestrian Safety

Measures protecting workers on foot from being struck by forklifts, trucks, or other mobile equipment.

Training

Powered Air Purifying Respirator

A battery-powered respirator that forces contaminated air through filters before the wearer inhales it.

Safety Equipment

Powered Platform

A mechanically driven platform used for building maintenance such as window washing on high-rise structures.

Safety Equipment

Personal Monitoring

Attaching a sampling device to a worker's breathing zone to measure individual exposure to airborne hazards.

Safety Equipment

Q

R

Repeat Violation

A violation of the same or a substantially similar standard that was previously cited within the past five years.

Compliance

Recordable Injury

A work-related injury or illness that requires medical treatment beyond first aid, per OSHA recordkeeping rules.

OSHA Standards

Respiratory Protection

Devices such as masks and respirators that protect workers from inhaling hazardous airborne contaminants.

Safety Equipment

Root Cause Analysis

A method of identifying the fundamental reason an incident occurred rather than only addressing symptoms.

Training

Repetitive Strain Injury

An injury caused by repeated motions or sustained postures that damage soft tissue over time.

Hazard Types

Rigging

The process of attaching loads to cranes or hoists using slings, shackles, and other hardware for safe lifting.

Safety Equipment

Respiratory Protection Program

A written program covering respirator selection, fit testing, training, and medical evaluation for users.

Compliance

Refresher Training

Periodic retraining to reinforce safety knowledge and update workers on new hazards or changed procedures.

Training

Risk Assessment

A process of evaluating the likelihood and severity of harm from identified hazards to prioritize controls.

Training

Risk Matrix

A table that plots hazard severity against probability of occurrence to rank and prioritize workplace risks.

Training

Regulator

A valve device that reduces high-pressure gas from a cylinder to a safe, usable working pressure.

Safety Equipment

Rescue Plan

A documented procedure for retrieving workers from elevated positions or confined spaces after a fall or emergency.

Emergency Response

Return to Work Program

A structured plan that helps injured employees transition back to productive work with modified or light duties.

Compliance

Radiation Safety

Practices and controls protecting workers from harmful exposure to ionizing and non-ionizing radiation sources.

Hazard Types

Respirable Dust

Airborne particles small enough to penetrate deep into the lungs, generally under 10 microns in diameter.

Hazard Types

Recordkeeping

The OSHA requirement to maintain logs and records of workplace injuries, illnesses, and safety training.

Compliance

S

Serious Violation

A violation where the hazard could cause death or serious physical harm and the employer knew or should have known.

Compliance

Safety Glasses

Impact-resistant eyewear meeting ANSI Z87.1 standards to protect workers from flying debris and splashes.

Safety Equipment

SCBA

Self-Contained Breathing Apparatus providing breathable air from a tank for use in oxygen-deficient atmospheres.

Safety Equipment

STEL

Short-Term Exposure Limit, the maximum concentration allowed for a continuous 15-minute exposure period.

Hazard Types

SDS

Safety Data Sheet, a document providing hazard information, handling procedures, and first aid for a chemical product.

Hazard Types

Safety Committee

A group of employees and managers who meet regularly to review safety performance and recommend improvements.

Training

Safety Meeting

A scheduled gathering where safety topics, policies, and recent incidents are discussed with the workforce.

Training

Scaffolding

A temporary elevated platform used to support workers and materials during construction or maintenance activities.

Safety Equipment

Safety Net

A mesh net installed below elevated work areas to catch falling workers when other fall protection is impractical.

Safety Equipment

Sling

A flexible lifting device made of wire rope, chain, or synthetic webbing used to connect loads to hoisting equipment.

Safety Equipment

Signal Person

A qualified worker who directs crane operations using standardized hand signals or radio communication.

Training

Shoring

A system of supports installed in excavations to prevent soil movement and protect workers from cave-ins.

Safety Equipment

Sloping

Cutting back trench walls at an angle to prevent cave-ins, with the angle determined by soil classification.

Hazard Types

Safety Shoes

Footwear with reinforced toes and slip-resistant soles designed to protect feet from crushing and puncture hazards.

Safety Equipment

Steel Toe

A reinforced toe cap in safety footwear that protects against falling objects and compression injuries.

Safety Equipment

Safety Harness

A full-body device with straps and D-rings designed to arrest falls and distribute impact forces safely.

Safety Equipment

Self-Retracting Lifeline

A fall arrest device that automatically adjusts cable length and locks when a fall is detected.

Safety Equipment

Spill Response

Procedures for containing, cleaning up, and reporting accidental releases of hazardous chemicals or materials.

Emergency Response

Spill Kit

A collection of absorbents, barriers, and PPE stored in a container for quick response to chemical spills.

Emergency Response

Safety Culture

The shared values, beliefs, and practices within an organization that prioritize workplace safety at every level.

Training

Safety Observation

A structured method of watching workers perform tasks to identify safe and at-risk behaviors for coaching.

Training

Safety Audit

A systematic review of a workplace safety program to verify compliance with regulations and internal standards.

Compliance

Safety Inspection

A walkthrough of the workplace to identify hazards, unsafe conditions, and deviations from safety standards.

Compliance

Silica

Crystalline silicon dioxide dust generated by cutting or grinding stone, concrete, or brick that causes silicosis.

Hazard Types

Safety Data Sheet

A 16-section document providing detailed information about a chemical product's hazards and safe handling.

Hazard Types

Signal Word

The word Danger or Warning on a GHS label indicating the severity level of the chemical hazard.

Hazard Types

Safety Sign

A visual marker using colors, symbols, and text to warn workers of hazards or indicate required safety measures.

Safety Equipment

Struck-By Hazard

A danger from flying, falling, swinging, or rolling objects that can hit and injure a worker.

Hazard Types

Section 11(c)

The OSH Act provision protecting employees from discrimination for exercising their safety and health rights.

OSHA Standards

Safety Training

Instruction given to workers on recognizing hazards, following safe procedures, and using protective equipment.

Training

Slip Trip Fall

The most common cause of workplace injuries, resulting from wet floors, cluttered walkways, or uneven surfaces.

Hazard Types

Suspension Trauma

A life-threatening condition caused by hanging motionless in a harness that restricts blood flow to vital organs.

Hazard Types

Scissor Lift

A mobile elevated work platform that raises vertically using a folding scissor mechanism.

Safety Equipment

Safety Label

A durable label affixed to equipment or containers communicating hazard warnings and safe use instructions.

Safety Equipment

Stored Energy

Residual energy in springs, capacitors, hydraulic lines, or compressed air that must be released before servicing.

Hazard Types

Safety Management System

A systematic framework of policies, procedures, and practices for managing workplace safety and health risks.

Compliance

Shock Absorber

A lanyard component that tears open during a fall to reduce the arresting forces on the worker's body.

Safety Equipment

Substance Abuse

The misuse of drugs or alcohol that impairs a worker's ability to perform job duties safely.

Compliance

T

U

V

W

Z