Occupational Safety and Health Definitions
An injury or illness is considered by the Occupational Safety and Health Administration to be work-related if an event or exposure in the work environment either caused or contributed to the resulting condition or significantly aggravated a pre-existing condition.
Recordable cases include work-related injuries and illnesses that result in:
- Loss of consciousness
- Days away from work
- Restricted work activity or job transfer
- Medical treatment (beyond first aid)
- Significant work related injuries or illnesses that are diagnosed by a
physician or other licensed health care professional. These include any
work related case involving cancer, chronic irreversible disease, a
fractured or cracked bone, or a punctured eardrum.
- Additional criteria that can result in a recordable case include:
- Any needlestick injury or cut from a sharp object that is
contaminated with another person's blood or other potentially infectious
- Any case requiring an employee to be medically removed under the
requirements of an OSHA health standard.
- Tuberculosis infection as evidenced by a positive skin test or
diagnosis by a physician or other licensed health care professional
after exposure to a known case of active tuberculosis.
- An employee's hearing test (audiogram) reveals 1) that the employee
has experienced a Standard Threshold Shift (STS) in hearing in one or both
ears (averaged at 2000, 3000, and 4000 Hz) and 2) the employee's total
hearing level is 25 decibels (dB) or more above the audiometric zero
(also averaged at 2000, 3000, and 4000 Hz) in the same ear(s) as the STS.
Days away from work, days of restricted work activity or job transfer
(DART) are cases that involve days away from work, or days of
restricted work activity or job transfer, or both.
Cases involving days away from work are cases requiring at
least one day away from work with or without days of job transfer or
Job transfer or restriction cases occur when, as a result of a
work-related injury or illness, an employer or health care professional
keeps, or recommends keeping an employee from doing the routine functions
of his or her job or from working the full workday that the employee would
have been scheduled to work before the injury or illness occurred.
Other recordable cases are recordable cases that do not involve
death, days away from work or days of restricted work activity or job
Incidence rate is the number of injuries and/or illnesses per 100
full-time workers and were calculated as: (N/EH) X 200,000 where:
- N = number of injuries and/or illnesses
- EH = total hours worked by all employees during the calendar year
- 200,000 = base for 100 full-time equivalent workers (working 40 hours
per week, 50 weeks per year).
Occupational injury is any wound or damage to the body resulting
from an event
in the work environment.
Skin diseases or disorders are illnesses involving the worker's
skin that are caused by work exposure to chemicals, plants or other
substances. Examples: Contact dermatitis, eczema, or rash caused by primary
irritants and sensitizers or poisonous plants; oil acne; friction blisters, chrome ulcers;
inflammation of the skin.
Respiratory conditions are illnesses associated with breathing
hazardous biological agents, chemicals, dust, gases, vapors, or fumes at
work. Examples: Silicosis, asbestosis, pneumonitis, pharyngitis, rhinitis or acute congestion; farmer's
lung, beryllium disease, tuberculosis, occupational asthma, reactive airways
dysfunction syndrome (RADS), chronic obstructive pulmonary disease (COPD), hypersensitivity pneumonitis,
toxic inhalation injury, such as metal fume fever, chronic obstructive
bronchitis and other pneumoconioses.
Poisoning includes disorders evidenced by abnormal concentrations
of toxic substances in blood, other tissues, other bodily fluids, or the breath
that are caused by the ingestion or absorption of toxic substances into the
body. Examples: Poisoning by lead, mercury, cadmium, arsenic, or other metals;
poisoning by carbon monoxide, hydrogen sulfide, or other gases; poisoning by
benzene, benzol, carbon tetrachloride, or other organic solvents; poisoning
by insecticide sprays such as parathion or lead arsenate; poisoning by other
chemicals such as formaldehyde.
Hearing loss Noise-induced hearing loss for recordkeeping purposes is
a change in hearing threshold relative to the baseline audiogram of an average
of 10 dB or more in either ear at 2000, 3000, and 4000 hertz and the employee's
total hearing level is 25 decibels (dB) or more above the audiometric zero (also
averaged at 2000, 3000, and 4000 hertz) in the same ear(s).
All other occupational illnesses Examples: Heatstroke, sunstroke,
heat exhaustion, heat stress and other effects of environmental heat;
freezing, frostbite, and other effects of exposure to low temperatures;
decompression sickness; effects of ionizing radiation (isotopes, x-rays,
radium); effects of nonionizing radiation (welding flash, ultra-violet rays,
lasers); anthrax; bloodborne pathogenic diseases such as AIDS, HIV,
hepatitis B or hepatitis C; brucellosis; malignant or benign tumors; histoplasmosis;
Nature of injury or illness names the principal physical
characteristic of a disabling condition, such as sprain/strain,
cut/laceration, or carpal tunnel syndrome.
Part of body affected is directly linked to the nature of injury
or illness cited, for example, back sprain, finger cut, or wrist and carpal
Source and secondary source of injury or illness identify the objects, substances, equipment, and
other factors that were responsible for the injury or illness incurred by the worker or that precipitated the event or
exposure. Examples are a heavy box, a toxic substance, fire/flame, and bodily motion of injured/ill worker.
Event or exposure signifies the manner in which the injury or
illness was produced or inflicted, for example, overexertion while lifting
or fall from ladder.
Median days away from work is the measure used to summarize the
varying lengths of absences from work among the cases with days away from
work. Half the cases involved more days and half involved less days than a
(2011 and forward) Musculoskeletal disorders (MSDs) include cases where the nature of the injury or
illness is pinched nerve; herniated disc; meniscus tear; sprains, strains, tears; hernia (traumatic and nontraumatic); pain,
swelling, and numbness; carpal or tarsal tunnel syndrome; Raynaud's syndrome or phenomenon; musculoskeletal system and
connective tissue diseases and disorders, when the event or exposure leading to the injury or illness is overexertion and
bodily reaction, unspecified; overexertion involving outside sources; repetitive motion involving microtasks; other and
multiple exertions or bodily reactions; and rubbed, abraded, or jarred by vibration.
(2010 and prior) Musculoskeletal Disorders (MSDs) include cases where the nature of the injury or illness
is sprains, strains, tears; back pain, hurt back; soreness, pain, hurt, except the back; carpal tunnel syndrome; hernia; or
musculoskeletal system and connective tissue diseases and disorders, when the event or exposure leading to the injury or illness
is bodily reaction/bending, climbing, crawling, reaching, twisting; overexertion; or repetition. Cases of Raynaudís phenomenon,
tarsal tunnel syndrome, and herniated spinal discs are not included. Although they may be considered MSDs, the survey classifies
these injuries and illnesses in categories that also include non-MSD cases.
Last Modified Date: November 20, 2012