A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
BACKGROUND CONCENTRATION: the level of a containment
present before the introduction of a new store.
BACILLUS: A rod-shaped bacterium.
BACTERIOCIDAL: Able to kill bacteria
BACTERIA: Microscopic organisms living in soil,
water, organic matter, or the bodies of plants
and animals characterized by lack of a distinct
nucleus and lack of ability to photosynthesize.
BACTERICIDE: Any agent that destroys bacteria.
BAKEOUT: a technique for reducing emissions of
new construction materials and furnishings, in
which the building temperature is raised (usually
to at least 90 degrees F) for several days to
enhance emissions of volatile compounds from new
materials, while running the ventilation system
at full capacity to exhaust the emissions.
BALANCING BY STATIC PRESSURE: Method of designing
local exhaust system ducts by selecting the duct
diameters that generate the static pressure to
distribute airflow without dampers.
BAROMETER: Instrument for measuring atmospheric
BED DEPTH: the amount of adsorbent, expressed
as units of length, parallel to the air stream,
through which the air stream passes.
BENIGN: Not malignant. A benign tumor is one
that does not metastasize or invade tissue. Benign
tumors may still be lethal, due to pressure on
BENZENE: A major organic intermediate and solvent
derived from coal or petroleum. The simplest member
of the aromatic series of hydrocarbons.
return to top
BERYL: A silicate of beryllium and aluminum.
BET METHOD: a method used to measure the surface
area of granular activated carbon.
BETA PARTICLE (BETA RADIATION): A small electrically
charged particle thrown off by many radioactive
materials. It is identical with the electron.
Beta particles emerge from radioactive material
at high speeds.
BIOAEROSOL: An airborne organic contaminant that
is either generated by or is itself a living organism;
examples of bioaerosols are fungi, bacteria, viruses,
protozoa, pollen, animal dander, insect emanations,
microbial endotoxins, and human skin scales.
BIOEFFLUENT: any odorous volatile organic compound
emitted by human beings, usually through perspiration
BIOHAZARD: A combination of the words biological
hazard. Organisms or products of organisms that
present a risk to humans.
BOILER: A closed container used to heat water
or to make steam.
BREAKTHROUGH VOLUME: the sampling volume for
which a significant amount (usually more than
1 %) of a VOC being drawn through a sorbent tube
appears in the tube effluent, i.e., the volume
that is sufficient for sampling but for which
there will be no significant loss of analytes;
also called retention volume.
BREATHING ZONE: the area of a room in which occupants
breathe as the stand, sit and lie down, generally
considered to be about 3-72 inches above the floor.
BRITISH THERMAL UNIT (BTU): The Btu is defined
as the heat required to raise the temperature
of one pound of water from one degree F.
return to top
BRONCHIAL TUBES: Branches or subdivisions of
the trachea (windpipe). A bronchiole is a branch
of bronchus, which is a branch of the windpipe.
BTU: British Thermal Unit - a measure of heat
BUILDING AIR INFILTRATION: the uncontrolled penetration
of outside air into a building through cracks
and seams, caused b the effects of wind or differences
in indoor/outdoor air pressure.
BUILDING ENVELOPE: the outer walls, windows,
doors, roof, and floors of a building: building
BUILDING-RELATED ILLNESS: a diagnosable illness
with identifiable symptoms whose cause can be
directly attributed to airborne pollutants within
the building (e.g., Legionnaires disease,
BYPASS: A pipe or duct, usually controlled by
valve or damper, for conveying a fluid around
an element of a system.
return to top