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Z94.13 - Occupational Health & Safety

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LACERATION. A term applied to cleanly cut incised wounds as well as jagged, irregular, blunt breaks or tears through the skin. Severity extends from small cuts which can be taped together to severe wounds with damage to underlying structures. The term is also applied to wounds of the mucous membranes and the surface of the eyes.

LASER. An acronym for Light Amplification by Stimulated Emission of Radiation.

LASER BURN. A punctate tissue injury caused by a beam of coherent light. Laser beams are particularly hazardous to the eye, where they may cause burns of the cornea, lens, or retina with consequent effects on visual acuity. A laser burn of the retinal fovea may destroy central vision sufficiently to produce legal blindness.

LATE EFFECTS OF RADIATION. Effects which occur with a long delay time following sublethal doses of radiation or following relatively low dose rates carried over a long period of time. Examples are carcinogenesis and premature aging.

LEAD INTOXICATION. A result of lead absorption, occurring from inhalation of lead dust or fumes or from swallowing lead dust.

LEAVE OF ABSENCE. Generally, excused time to be absent from work or duty, usually for an extended time, without loss of job or seniority.

LEGAL LIABILITY. Liability imposed by law as opposed to liability arising from an agreement or contract.

LESION. Injury, damage, or abnormal change to body tissue or organ, especially one that leads to impairment or loss of function of the part involved, or, even if it produces no impairment of function, expresses a symptom or sign of disease.

LEVEL (NOISE). The logarithm of the ratio of the measured quantity to a reference quantity of the same kind. The base of the logarithms, the reference quantity, and kind of level must be specified.

LIABILITY INSURANCE. Insurance which obligates the insurance company to pay any liability for which the insured may be covered and, also at the expense of the company, to defend any damage suits brought against it  to enforce such liability, thus protecting it from liability and expense of litigation growing out of claims in which it is involved. Insurance which agrees to reimburse the policyholder for sums that may be required to pay others as the result of negligence.

LIFE EXPECTANCY. The average number of years an individual is expected to live if current mortality trends continue to apply. It is a hypothetical measure and indicator of current health and mortality conditions.

LIFE INSURANCE PLAN. Group term insurance coverage for employees, paid for in whole or in part by the employer, providing a lump-sum payment to a worker's beneficiary in the event of death. (See HEALTH AND INSURANCE PLAN.)

LIFE TABLE. A statistical method used to summarize the pattern of mortality and survival in population.

LIFELINE. A rope designed and utilized to provide fall protection that must be secured above the point of operation to an anchorage or structural member.  It must also be capable of supporting a minimum specified dead weight.

LIMIT SWITCH. A switch fitted to electric lifts, traveling cranes, etc., in order to cut off the power supply if the liftcar or moving carriage travels beyond a certain specified limit.

LOAD LIMIT. The upper weight limit capable of safe support by a vehicle or floor. The designer of floors to meet load limit requirements should consult ANSI/ASCE Standard 7-95, Minimum Design Loads for Buildings and Other Structures.

LOAD WEIGHT OR ALLOWABLE LOAD. Refers to highest weight of load to be carried by a vehicle safely.

LOCAL EFFECTS OF RADIATION. Effects limited to a specific organ or system due to specific irradiation of that organ or increased sensitivity of the organ.

LOCKOUT-TAGOUT. A program or procedure that prevents injury by eliminating unintentional operation or release of energy within machinery or processes during set-up, start-up, cleaning and clearing jams, or maintenance repairs.


LOSS. In insurance it means the amount the insurer is required to pay because of a judgment that requires the company to pay by virtue of the terms of the insurance contract. Also refers to the overall financial result of some operation, as opposed to  profit.-

LOSS CONTROL. A program designed to minimize accident-based financial losses. The concept of total loss control is based on studies of  near misses- (noninjury accidents) and on detailed analysis of both indirect and direct accident costs. Property damage as well as injurious and potentially injurious accidents are included in the analysis.

LOSS PREVENTION. A before-the-loss program designed to identify and correct potential accident problems before they result in actual financial loss or injury.

LOSS RATIO (INSURANCE). A fraction calculated by dividing the amount of losses by the amount of premiums. Expressed as a percentage of the premiums. Various bases are used in calculating the loss ratio, e.g.,  earned premium loss ratio,-  written premium loss ratio,- etc.

LOSS RESERVE. An estimate of the amount an insurer expects to pay for losses incurred but not yet due for payment.


LOST TIME INJURY/ILLNESS. A work injury/illness which results in death or disability and in which the injured person is unable to report for duty on the next regularly scheduled shift. (See INJURY.)

LOST WORKDAY CASES. Cases which involve days away from work or days of restricted work activity, or both.

LOST WORKDAYS. The number of workdays (consecutive or not), beyond the day of injury or onset of illness, the employee was away from work or limited to restricted work activity because of an occupational injury or illness. (See DAYS OF DISABILITY.)

LOUDNESS. The intensity attribute of an auditory sensation, in terms of which sounds may be ordered on a scale extending from soft to loud. Loudness depends primarily upon the sound pressure of the stimulus, but it also depends upon the frequency and wave form of the stimulus.

LOUDNESS LEVEL. A subjective method for rating loudness in which a 1000 Hz tone is varied in intensity until it is judged by listeners to be equally as loud as a given sound sample. The loudness level in phons is taken as the sound pressure level, in decibels, of the 1000 Hz tone.

LOWER EXPLOSIVE LIMIT (LEL). The minimum concentration of combustible gas or vapor in air of flammable liquids or gases below which propagation of flame does not occur on contact with a source of ignition.

LUMEN. Under the  common- system, it was defined as the flux on one square foot of a sphere, one foot in radius, with a light source of one candle at the center that radiates uniformly in all directions. Under SI, luminous flux is measured in lumen units (symbols: lm) and has as its formula cd x sr which are the SI Base Units of candela and steradian for solid angle. Thus, the lumen is the luminous flux emitted in a solid angle of one lumen uniformly distributed in a solid angle of one steradian by a point source having a uniform intensity of one candela. (See LUX.)

LUMINAIRE. A complete lighting unit consisting of a lamp or lamps together with parts designed to distribute the light, position and protect the lamps and connect the lamps to the power supply.

LUMINESCENT. Emitting light not due to high temperatures, usually caused by excitation by rays of a shorter wavelength.

LUNG VOLUMES. inspiratory capacity (IC) - Maximal volume inspired from resting expiratory level.   expiratory reserve volume (ERV) - Maximal volume expired from resting expiratory level.  vital capacity (VC) - Maximal volume expelled by complete expiration after a maximal inspiration.  functional residual capacity (FRC) - Volume of gas in the lungs at the resting expiratory level.  residual volume (RV) - Volume of gas in the lungs after maximal expiration.  total lung capacity (TLC) - Volume of gas in the lung after a maximal inspiration; that is, the VC + RV.   tidal volume (TV) - Volume of gas inspired or expired during each breathing cycle.

LUX. The illuminance produced by a luminous flux of one lumen uniformly distributed over a surface of one square meter.

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