Degrees Celsius (Centigrade)
The temperature on a scale in which the freezing point of water is 0oC and the boiling point is 100oC. To convert to Degrees Fahrenheit, use the following formula: oF = (oC x 1.8) + 32.

Degrees Fahrenheit
The temperature on a scale in which the boiling point of water is 212oF and the freezing point is 32oF.

Density
The mass per unit volume of a substance. For example, lead is much more dense than aluminum.

Dermatitis
Inflammation of the skin from any cause.

Dermatosis
A broader term than dermatitis; it includes any cutaneous abnormality, thus encompassing folliculitis, acne, pigmentary changes, and nodules and tumors.

DOL
US Department of Labor. OSHA and MSHA are part of the DOL.

Dose-response relationship
Correlation between the amount of exposure to an agent or toxic chemical and the resulting effect on the body.

DOT
US Department of Transportation.

Dusts
Solid particles generated by handling, crushing, grinding, rapid impact, detonation, and decrepitation of organic or inorganic materials, such as rock, ore, metal, coal, wood and grain. Dusts do not tend to flocculate, except under electrostatic forces; they do not diffuse in air but settle under the influence of gravity.

Dyspnea
Shortness of breath, difficult or labored breathing.