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Absorption |
The process of soaking up gas, vapor, liquid or
aerosol substance. This includes chemical and biological aerosols which can be
absorbed through the skin and chemical contaminants absorbed in the soil. |
|
Acidic |
Substances that react with water to produce an
acid. They can turn water acidic by producing a pH less than 7.These
substances have a sour odor. Many are corrosive to tissues and cause burns. |
|
Active Sampling |
Continuous collection of airborne
contaminants, for a specific period of time, at a specific flow rate, by pulling
a vacuum of air through a collection media. |
|
Adsorption |
The assimilation of gas, vapor or dissolved
matter by the surface of a solid or liquid. |
|
Aerodynamic Diameter |
The dynamics of particle movement in
gases, describing the shape and density of dust particles at a specific velocity
and their atmospheric interaction with moving objects. |
|
Aerosol |
A gaseous suspension of fine solid or liquid
particles. This can be substances such as paint, detergent, insecticide packaged
under pressure with a gaseous propellant for release as an aerosol. |
|
Air Volume |
The total volume of air passing through a
sampling medium |
|
Alkaline |
Substances that react with water to product an
alkali. They can turn water alkaline by producing a pH higher than 7.They have
a bitter odor and sting nasal passages. They are corrosive to tissues and cause
burns. |
|
Blank Sample |
Also called a control sample. It is a
duplicate sample media that has undergone all the preparation to sample, without
actual sampling. This control sample is send with the actual sample to the lab
for identical analysis. |
|
Ceiling Value |
The maximum exposure concentration which
should not be exceeded over an 8 hour period. |
|
Closed-Face Sampling |
Filter sampling cassettes, 2 or 3
piece, with the cover attached and the plug removed. |
|
Constant Flow |
is the flow rate a pump must maintain during
the entire sampling period. |
|
Cut-Point (50%) |
The efficiency which a sampling device or
cyclone is measured based on particle size. |
|
Cyclone |
A sampling device used to collect and separate respirable particulate mass. The rapid circulation of air separates particles
according to size. |
|
Desorption |
To remove an absorbed or adsorbed substance from
a liquid or gas environment, including soil. See also,
Thermal Desorption. |
Diffusive Sampling
(Passive) |
Collection of airborne gases
and vapors, independently, through a diffusion barrier onto a sorbent medium
without the use of a vacuum source. |
|
Dust |
A solid, mechanically produced particle with sizes
varying form submicroscopic to visible or macroscopic. |
|
Foam Sampler |
A sampling device containing a foam insert
for particle size selective aerosol monitoring. |
|
Fog |
A mist of sufficient concentration to reduce
perception and visibility. |
|
Fume |
Odorless, invisible condensation particles of
extremely small particle size, generally <1µm. |
|
Gas |
A state of matter different from a solid or liquid by
very low density and viscosity. It expands and contracts with changes in the
environment and has the ability to readily diffuse into any container. |
|
Grab Sampling |
To collect a sample directly into a sampling
device over a period of time. |
|
Gravimetric Analysis |
To determine the particle
contamination level by calculating the weight difference of a filter before and
after sampling. |
|
High Flow Sampling |
Air sampling at flow rates
> 750ml/min. |
|
Inhalable Particulates |
Hazardous particles,
>100µm which can penetrate the
respiratory tract |
|
Inert Gases |
Gases which create a respiratory hazard by
displacing air and producing an oxygen deficiency. These substances do not
react with other substances under most conditions. |
|
Integrated Sampling |
To
integrate air sampling results over a long period of time |
|
Low Flow Sampling |
Air sampling at flow rates
< 500ml/min. |
|
Matched Weight Analysis |
To determine the particle
contamination level by calculating the weight difference of two matched filters
before and after sampling. |
|
Mist |
Visible liquid condensation with particles varying in
size from submicroscopic to visible or macroscopic. |
|
Open-Face Sampling |
Filter sampling cassettes, 3 piece,
with the center ring attached, holding the filter in place, and the cover
removed. |
|
Organic |
These hazards are associated with carbon compounds
found in the environment. |
|
Particulate |
A small particle produced by mechanical
disintegration in the environment. These can become airborne through such
processes as spraying, grinding, drilling and blasting, or by reactions such as
combustion, vaporization, distillation, condensation. They are classified
according to size and how they are distributed, such as a dust, spray, vapor,
fume, mist, fog and smoke. |
|
Passive Sampling (Diffusive) |
Collection of airborne gases
and vapors, independently, through a diffusion barrier onto a sorbent medium
without the use of a vacuum source. |
|
Preloaded Cassettes |
Sampling cassettes which have been
preloaded, in a controlled environment, with the appropriate filter and support
required to perform the prescribed sampling. |
|
Preweigh |
The process of weighing a sample collection media
before actual sampling. |
|
Respirable Particulates |
Particles which are
< 4µm in size and hazardous, when
deposited in the gas exchange region of the lungs |
|
Respiratory Tract |
The respiratory tract begins at the
nasal entrance, where particles are inhalable and continues through the thoracic
cavity and down into the respirable gas exchange regions of the lungs. See also
Inhalable, Thoracic and Respirable particulates. |
|
Sampling Media |
Materials and devices used to collect
airborne contaminants such as filters, cassettes, sorbent tubes and bags. |
|
Sampling Parameters |
A constant or fixed, limit or range,
set according to the sampling requirements and the method applied. |
|
Sampling Train |
The entire sampling system beginning at the
collection point and continuing through the sampling media, tubing and into the
vacuum source. |
|
Short-Term Exposure Limit |
The 15 minute time-Weighted
Average exposure that should not be exceeded during any part of the work day. |
|
Smoke |
A system, produced by combustion, pyrolysis or
chemical reaction of substances, which release visible and invisible gaseous
solid and liquid particles into the air. Smoke is usually of sufficient
concentration to reduce perception and visibility. |
|
Solvent Desorption |
Solvent Desorption requires the use of
solvents to extract adsorbed chemicals from sorbent material. |
|
Spray |
A visible liquid containing mechanically produced
particle with sizes varying from visible to macroscopic. |
|
Thermal Desorption |
The use of heat to remove an absorbed or
adsorbed substance from a liquid or gas environment, including soil. |
|
Thoracic Particulates |
Hazardous particles,
<10µm
which can penetrate the lung pathways and gas exchange region of the lungs.
Also see Respiratory Tract. |
|
Threshold Limit Values (TLV's) |
The limit of exposure a
worker can withstand. For example, a sensitized worker may have a lower TLV than a
novice. |
|
Time Weighted Average (TWA) |
The average exposure level
calculated by weighing samples, at different times, throughout a workday. OSHA
standards are based on an 8 hour day. The TWA is determined by dividing the
total sample weight by the total sampling time. |
|
Total Dust |
The total amount collected on the primary
collection filter cassette. |
|
Vapor |
A gaseous substance that is capable of becoming
liquid when the temperature is reduced. |
|
Virtual Cyclone |
The virtual cyclone is used, similar to a
standard cyclone, to collect and separate respirable particulate mass. The
virtual chamber allows the air to continuously circulate within the cyclone
separating particles according to size, instead of directly funneling down into
the grit pot. |
|
Volatile Organic Compounds (VOC's) |
Carbon compounds capable
of being vaporized into the environment. These can be explosive such as
alcoholic compounds. |
