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Absorption – The entry of a substance into the body through broken or unbroken skin.
Accident – An unplanned event that results in harm to people, damage to property or
loss to process.
Accident Prevention – The systematic application of recognized principles to reduce
incidents, accidents, or the accident potential of a system or organization.
Acute Effect – A change that occurs in the body within a relatively short time (minutes,
hours, days) following exposure to a substance.
Agent – Any substance, force, organism or influence that affects the body, a part of the
body, or any of its functions. The effects may be beneficial or harmful.
Asphyxiant – A vapour or gas that can either reduce the oxygen content in the air or
interfere with the body’s ability to use oxygen. Exposure to an asphyxiant can result in
unconsciousness or death due to being unable to breathe.
Audiometric Testing – Tests that are conducted to determine the hearing ability of a
person. These tests may be used to establish an employee’s baseline hearing, to identify
any subsequent hearing loss, and to monitor the effectiveness of noise controls.
Bilateral Work Stoppage – Stoppage of work under the direction of the worker
certified member and the management certified member when both members have reason
to believe that dangerous circumstances exist.
Biological Agent – Any living organism (for example, virus or bacteria) that affects
the body, a part of the body, or any of its functions. The effects may be beneficial
or harmful.
Breathing Zone – The area surrounding the worker’s head. The make-up of air in this
area is thought to be representative of the air that is actually breathed in by the worker.
By-Product – The product formed or released by a material during use in a process.
This is produced in addition to the principle product. A by-product may be toxic,
flammable or explosive.
Carcinogen – A chemical, physical or biological agent that can cause cancer in humans
or animals.
Chemical Agent – A chemical substance that affects the body, a part of the body, or any of its functions. The effects may be beneficial or harmful.
Chronic Effect – A change that occurs in the body over a relatively long time (weeks,
months, years) following repeated exposure or a single over-exposure to a substance.
Chronic Exposure – Repeated exposure to a hazardous agent.
Confined Space – A space in which a hazardous gas, vapour, dust or fume may collect
or in which oxygen may be used up because of the construction of the space, its location,
contents, or the work activity carried out in it. It is an area which is not designed for
continuous human occupancy and has limited opening for entry, exits or ventilation.
Contaminant – An unwanted material (for example, radioactive, biological or
chemical) that is likely to harm the quality of the working environment. The most
common workplace contaminants are chemicals that may be present in the form of dusts,
fumes, gases or vapours.
Controls – Measures designed to eliminate or reduce hazards or hazardous exposures.
Examples include: engineering controls, administrative controls, personal protective
equipment. Hazards can be controlled at the source, along the path to the worker, or
at the worker.
Danger Zone – An area or location where the probability of injury is high (for example,
in the vicinity of saw blades).
Dermal – Relating to the skin.
Dermatitis – Inflammation of the skin. Symptoms of dermatitis may include: redness,
blisters, and cracks in the skin.
Disabling Injury – An injury that prevents a person from coming to work or doing his
or her usual job duties.
Due Diligence – The taking of every precaution reasonable in the circumstances for the
protection of the health and safety of workers.
Emergency Plan – Detailed procedures for responding to an emergency, such as a fire
or explosion, a chemical spill, or an uncontrolled release of energy. An emergency plan is
necessary to keep order, and minimize the effects of the disaster.
Engineering Controls – A category of hazard control that uses physical/engineering
methods to eliminate or minimize the hazard. Examples of engineering controls include:
ventilation, isolation, elimination, enclosure, substitution and design of the workplace or
Ergonomics – An applied science that studies the interaction between people and the
work environment. It focuses on matching the job to the worker.
Exposure Records – The records kept by an employer, or company doctor or nurse
of an employee’s exposure to a hazardous material or physical agent in the workplace.
These records show the time, level and length of exposure for each substance or
agent involved.
Flash Point – The lowest temperature at which a liquid will give off enough vapours
to form a mixture that will burn if ignited. The lower the flash point, the higher the risk
of fire.
Fugitive Emission – A gas, liquid, solid, vapour, fume, mist, fog or dust that escapes
from process equipment, emission control equipment or a product.
Fume – Finely divided solid particles that are formed when a hot metal vapour cools
and condenses. Fumes are usually associated with molten metals (for example, copper,
lead or zinc and are often accompanied by a chemical reaction such as oxidation.
Gas – A formless substance that expands to occupy the space of its container (for
example, methane, acetylene).
Glare – Bright light that interferes with a person’s ability to see. Glare causes discomfort
and can lead to eyestrain and headaches.
Hazard – The potential of any machine, equipment, process, material (including
biological and chemical) or physical factor that may cause harm to people, or damage to
property or the environment.
Hazardous Material – Any substance that may produce adverse health and/or safety
effects to people or the environment.
Health and Safety Policy – A policy is a statement of intent, and a commitment to
plan for coordinated management action. A policy should provide a clear indication of a
company’s health and safety objectives. This, in turn, will provide direction for the health
and safety program.
Health and Safety Program – A systematic combination of activities, procedures, and facilities designed to ensure and maintain a safe and healthy workplace.
Hypersensitive – The condition of being reactive to substances that normally would
not affect most people.
Incident – An unwanted event which, in different circumstances, could have resulted in
harm to people, damage to property or loss to a process. Also known as a near miss.
Incompatible – A term used to describe materials that could cause dangerous reactions
if they come in direct contact with one another.
Industrial Hygiene – A science that deals with the anticipation, recognition, evaluation, and control of hazards in the workplace. These hazards may cause sickness, harm to employee health, discomfort, and inefficient performance on the job.
Ingestion – The swallowing of a substance.
Inhalation – The breathing in of an airborne gas, vapour, fume, mist or dust.
Injection – To force or drive liquid or gas into the body.
Irritant – A substance which, in sufficient quantities, can inflame or irritate the eyes, skin or respiratory system (lungs, etc.). Symptoms include pain and reddening.
Latent Period – The time that passes between exposure to a harmful substance or agent
and the first sign(s) of damage or illness. Also known as incubation period.
Localized – Restricted to one spot or area in the body and not spread throughout it.
Material Safety Data Sheet (MSDS) – A form that contains detailed information
about the possible health and safety hazards of a product and how to safely store, use and
handle the product. Under the federal Hazardous Products Act, suppliers are required to
provide MSDSs for all hazardous materials, as a condition of sale.
Nature of Injury or Illness – The main physical characteristics of a workplace injury
or illness (for example, burn, cut, sprain, dermatitis, hearing loss).
Nuisance Dust or Particle – Dust that does not cause disease or harmful effects when
exposures are kept at reasonable levels.
Occupational Illness – A harmful condition or sickness that results from exposure
in the workplace to a biological, chemical, or physical agent or an ergonomic hazard.
See ergonomics.
Occupational Safety – The maintenance of a work environment that is relatively free
from actual or potential hazards that can injure employees.
Personal Monitoring – A technique used to determine an individual’s personal
exposure to a chemical, physical or biological agent. This is done by means of a sampling
device worn on the worker’s body (e.g., personal monitor). The monitoring of hazardous
chemicals is done at the breathing zone; the monitoring of noise is done at the ears.
Personal Protective Equipment (PPE) – Any device worn by a worker to protect
against hazards. Some examples are: respirators, gloves, ear plugs, hard hats, safety
goggles and safety shoes.
Procedure – A step-by-step description of how to do a task, job, or activity properly.
Quorum – The minimum number of management and worker members that the joint
health and safety committee determines must be present in order to carry out its business.
Respirable Particles – Small particles that can be breathed in and reach parts of the
respiratory system where they may have a harmful effect (for example, the lungs).
Risk – The probability of a worker suffering an injury or health problem, or of damage
occurring to property or the environment as a result of exposure to or contact with
a hazard.
Route of Entry – The method by which a contaminant can enter the body. There are
four main routes of entry. Contaminants can be breathed in, swallowed, absorbed through
the skin, or injected into the bloodstream.
Solvent – A substance that dissolves other substances. Many solvents are flammable.
Source of Injury or Illness – The object, substance, exposure, or body motion that
directly caused a workplace injury or illness (for example, boxes, powered hand tools,
acids, lead, cold, running, walking).
Standard – A guideline, rule, principle, or model that is used as a means to compare,
measure or judge performance, quality, quantity, etc.
Synergistic Effects – The health effects of two or more substances or agents that are
greater than the sum of their separate effects.
Systemic – Spread throughout the body; affecting one or more body parts or systems.
Task Analysis – A technique used to identify, evaluate, and control health and safety
hazards linked to particular tasks. A task analysis systematically breaks tasks down into
their basic components. This allows each step of the process to be thoroughly evaluated.
Also known as job task analysis.
Threshold Limit Value (TLV) – A threshold limit value refers to the airborne
concentration of a substance to which it is believed that nearly all workers may be
repeatedly exposed day after day (for 8 hours per day) without harmful effect. Because
of individual susceptibility, however, a small percentage of workers may experience
discomfort from substances in concentrations at or below the threshold limit. A smaller
percentage may be affected more seriously by aggravation of a pre-existing condition or
by the development of an occupational illness.
Toxic – Harmful or poisonous.
Toxic Substance – Any substance that can cause acute or chronic effects to a person or is suspected to cause disease or injury under certain conditions.
Trade Name – The trademark name or commercial name for a material.
Type of Injury/Illness – The event that directly resulted in a workplace injury or
illness (for example, struck against, caught in, over-exertion).
Unilateral Work Stoppage – Stoppage of work under the direction of either the
worker certified member or the management certified member when the member has
reason to believe that dangerous circumstances exist.
Unstable – The tendency of a material to break down or to undergo other unwanted
chemical changes during normal handling or storage.
Volatility – The tendency or ability of a liquid to quickly vapourize into the air.
Examples of volatile liquids include alcohol and gasoline. Liquids that are volatile must
be carefully dispensed and stored. This includes paying special attention to temperature.
Work Practices – Procedures for carrying out specific tasks which, when followed,
will ensure that a worker’s exposure to hazardous situations, substances or physical
agents is controlled by the manner in which the work is carried out.
Workplace Design – The planning of workplace environments, structures and
equipment so that the potential for injury and illness is reduced or eliminated.
Workplace Hazardous Materials Information System (WHMIS) – An
information system implemented under the federal Hazardous Products Act and
provincial occupational health and safety laws to ensure communication of
information on hazardous materials. The information delivery system under WHMIS
requires 1) labels, 2) material safety data sheets (MSDSs), and 3) worker education and
training programs.
Workplace Inspection – A regular and careful check of a workplace or part of a
workplace in order to identify health and safety hazards and to recommend corrective
action. Workplace factors that have the potential to cause injury or illness to employees
include: equipment, materials, processes or work activities, and the environment.
Glossary of Occupational Health & Safety Terms © Industrial Accident Prevention Association, 2007, used with permission