Glossary of Terms: B

Balancing by dampers
Design process for local exhaust systems using adjustable dampers to distribute airflow
Balancing by static pressure
Design process for local exhaust systems using selected duct diameters to generate static pressures to provide distributed airflow without dampers
Bandwidth
A range of frequencies defined by an upper band-edge frequency, f2, and a lower band-edge frequency, f1. The bandwidth is the difference between the two frequencies (f2 - f1 Hz).
Barrier cream
A cream designed to protect the hands and other parts of the skin from exposure to harmful agents. Also known as protective hand cream.
Base
A compound that reacts with an acid to form a salt. It is another term for alkali.
BASEEFA
British Approvals Service for Electrical Equipment in Flammable Atmospheres. UK Safety Certification
Benign
Not malignant. A benign tumor is one which does not metastasize or invade tissue. Benign tumors may still be lethal, due to pressure on vital organs.
Bilateral work stoppage
Stoppage of work under the direction of the worker certified member and the management certified member when both members have reason to believe that dangerous circumstances exist.
Biohazard
A combination of the words biological hazard. Organisms or products of organisms that present a risk to humans.
Biological agent
Any living organism (for example, virus or bacteria) that affects the body, a part of the body, or any of its functions. The effects may be beneficial or harmful.
Biological monitoring
The use of medical tests (for example, blood, urine, exhaled air) to determine whether a person has been or is being exposed to a substance.
BMS
Building Management System.
Boiling point
The temperature at which a liquid changes to a vapor. Also, the temperature at which the vapor pressure of a liquid equals atmospheric pressure.
Bonding
The use of low-resistance material to connect two or more conductive objects that would likely undergo a build-up of static electricity. Bonding prevents the unwanted release of electrical energy, such as sparks. E.g., transferring of one flammable liquid from one container to another can release electrical energy if it is not bonded.
Brake horsepower curve
graphical representation of brake HP at different airflow rates for a fan
Brake horsepower
the power needed to spin the fan (neglecting motor/fan drive inefficiencies), 1 HP = 33,000 ft.-lb per min.
Branch (or path) of greatest resistance
Path from a hood to the fan (and exhaust stack if used) that causes the greatest pressure loss in duct system
Breathing zone sample
air samples collected in a worker’s breathing zone to assess inhalation exposure to airborne contaminants.
Breathing zone
The area surrounding the worker’s head. The make-up of air in this area is thought to be representative of the air that is actually breathed in by the worker. Used for toxic gas monitoring.
Bridge circuit
Wheatstone Bridge circuit used in catalytic detector design.
Broadband
Broadband measurements from a sound level meter refer to measurements made over the applicable frequency range of the instrument.
Bump test
Check of basic functionality by exposure to test gas, resulting in a gas indication or alarm condition.
Byproduct
The product formed or released by a material during use in a process. This is produced in addition to the principle product. A by-product may be toxic, flammable or explosive.