Not Otherwise Specified

Non-Attainment (CAA)

North American (DOT).  When NA precedes a four-digit number, it
indicates that the identification number is used in the United States and Canada to identify a hazardous
material (HM) in transportation.

National Ambient Air Quality Standards (Clean Air Act) (40 CFR, Part 50).

National Agricultural Chemicals Association

National Association of Corrosion Engineers

North American Free Trade Agreement

North American Industry Classification System:  A method of
classifying various facilities.  Replaced the 1987 Standard Industrial
Classification (SIC) code system for the collection of statistical economic data.

Stupor or unconsciousness produced by chemical substances.

The result of several processes, such as biodegradation, abiotic
transformation, mechanical dispersion, sorption and dilution that reduces the
contaminant concentration in the Environment.

National Contingency Plan (40 CFR 300); Superfund procedures and standards
for clean up of hazardous waste sites.

National Defense Council

National Electrical Code

Destruction of body tissue

National Environment Policy Act

National Emission Standards for Hazardous Air Pollutants (CAA: 40 CFR, PART
60); a set of national emission standards for a list of hazardous pollutants
emitted from specific classes or categories of new and existing sources. 
These include and were introduced in the Clean Air Act Amendments of
1997.  Under Title III of the 1990 CAAA, hazardous air pollutants are by
definition included in the NESHAP’s program.

The process by which acid or alkaline properties of a solution are altered
by the addition of reagents to bring the hydrogen and hydroxide concentrations
to equal value or to a neutral pH of 7.

A small particle, typically found within an atom’s nucleus, that possesses
no electrical charge.

National Fire
Academy

National Fired Protection Association; an international voluntary
membership organization to promote and improved fire protection.