A filtering system that has characteristics which roughly match the response characteristics of the human ear at sound levels between 55 and 85 dB. B-scale measurements are often referred to as dB(B).

The total of all sources of interference in a system used for the production, detection, measurement or recording of a signal, independent of the presence of the signal.

Natural radiation in the environment including cosmic rays and radiation from naturally radioactive elements; it may also mean radiation from sources other than the one directly under consideration.

Band pressure level of a sound for a specified frequency band is the sound pressure level for the sound contained within the restricted band. The reference pressure must be specified.

Tissue damage resulting from expansion or contraction in gas-filled spaces within or adjacent to the body. As external pressure varies with ascent or descent, gas volume within these spaces varies resulting in tissue distortion, edema, and hemorrhage. It is the most common occupational disease of divers.

Protection for operators and other individuals from hazard points on machinery and equipment. adjustable barrier guard - An enclosure attached to the frame of the machinery or equipment with front and side sections which can be adjusted. fixed barrier guard - A point of operation enclosure attached to the machine or equipment. gate or movable barrier guard - A device designed to enclose the point of operation completely before the clutch can be engaged. interlocked barrier guard - An enclosure attached to the machinery or equipment frame and interlocked with the power switch so that the operating cycle cannot be started unless the guard is in its proper position.

Bursitis of the knee joints due to friction or vibration common in mining.

Estimate of the body heat stress of an average man (standard man) for various degrees of activity; also relates to his sweating capacity.

(See DECOMPRESSION SICKNESS.)

The property of a neoplasm, of non-invasiveness; i.e., the neoplasm remains localized.

Disease due to inhalation of beryllium or beryllium compounds. Acute berylliosis is characterized by bronchitis and pneumonia. The chronic disease which may follow is a systemic disease with pathologic changes not only in the lung, but in numerous other body tissues including the liver, spleen, kidneys, heart, skin, and bone.

A consistent tendency for an estimate to overestimate or underestimate the true population value.

Consistent error due to differences in accuracy or completeness of recall to memory of prior events or experiences.

Consistent error due to differences in characteristics between those who volunteer to participate in a study and those who do not.

The application of engineering knowledge to the fields of medicine and biology.

A combination of the words biological and hazard. A risk to humans presented by organisms or products of organisms.

Cause of acute and chronic infections, parasitism, and toxic and allergic reactions to plant and animal agents. Infections may be caused by bacteria, viruses, rickettsia, chlamydia, or fungi. These agents act on or within the body to produce disease or infection.

The time required for a given species, organ, or tissue to eliminate half of a substance which it takes in.

Reactions of the body due to exposure to physical, chemical, or biological agents.

Any alteration in a biological system resulting from exposure to radiation. Effects may or may not be hazardous or detrimental to the system.

The direct quantitative analysis of expired air, body fluids or tissue for the presence of the hazardous agent or its metabolites and/or evidence of biologic impairment quantified by the use of physiologic, psychometric, biochemical tests.

The application of mechanical laws to living structures, specifically to the locomotor systems of the human body.

Concerned with the mechanical properties of human tissue, particularly the response of tissue to mechanical stress. A major focus is the prevention of overexertion disorders of the lower back and upper extremities.

The application of statistical methods to the study of numerical data based on biological or biomedical observation and phenomena.

The observation over time of persons born within a particular period of time, such as those born during a one-year or a five-year period.

Experiment in which either the experimenter or the subject(s) does not know the group to which the subject(s) have been allocated. The intent of blind procedures is to eliminate the biases and prejudices of the subject(s) or of the investigator.

An autonomous board established to certify the professional and technical competence of individual practitioners in the safety field.

Injury to a human being, as opposed to injury to property.

Standards prescribing requirements for the design, construction, testing, and installation of boilers and unfired pressure vessels. (e.g., American Society of Mechanical Engineers, etc.)

The light intensity of a surface in a given direction per unit emulsive area as projected on a plane of the same direction. (See ILLUMINATION.)

An assembly of regulations which set forth the standards to which buildings must be constructed.

A sac or sac-like structure containing a fluid and situated at places in tissues at which friction would otherwise develop. In industry the bursae of interest are at the shoulder, the elbow, and the anterior surface of the knee.

Inflammation of a bursa, sometimes with development of calcium deposits. Causes of bursitis are multiple, but inflammation of the shoulder bursa may be associated with repetitive or unusual motion. Bursitis of the elbow or knee may be due to prolonged pressure or blunt trauma.

A pulmonary disease occurring among cotton textile workers and preparers of flax and soft hemp, due to inhalation of cotton or flax dust. The acute form is characterized by tightness of the chest, wheezing, and cough on return to work after a brief absence. The chronic form, occurring after years of exposure is marked by permanent dyspnea.