OHD Quantifit2, Руководство пользователя

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Chapter 25 | Appendix C: Terminology |
25
Appendix C: Terminology
Loose-fitting facepiece a respiratory inlet
covering that is designed to form a partial seal
with the face.
Maximum use concentration (MUC) the
maximum atmospheric concentration of a
hazardous substance from which an employee
can be expected to be protected when wearing a
respirator and is determined by the assigned
protection factor of the respirator or class of
respirators and the exposure limit of the
hazardous substance. The MUC can be
determined mathematically by multiplying the
assigned protection factor specified for a
respirator by the required OSHA permissible
exposure limit, short-term exposure limit, or
ceiling limit. When no OSHA exposure limit is
available for a hazardous substance, an employer
must determine an MUC based on relevant
available information and informed professional
judgment.
Negative pressure respirator (tight fitting) a
respirator in which the air pressure inside the
facepiece is negative during inhalation with
respect to the ambient air pressure outside the
respirator.
Oxygen deficient atmosphere an atmosphere
with an oxygen content below 19.5% by volume.
Permissible Exposure Limit (PEL) is a
regulatory limit on the amount or concentration
of a substance in the air.
Positive pressure respirator a respirator in
which the pressure inside the respiratory inlet
covering exceeds the ambient air pressure
outside the respirator.
Powered air-purifying respirator (PAPR ) an
air-purifying respirator that uses a blower to
force the ambient air through air-purifying
elements to the inlet covering.
Pressure demand respirator a positive pressure
atmosphere-supplying respirator that admits
breathing air to the facepiece when the positive
pressure is reduced inside the facepiece by
inhalation.
Qualitative fit test (QLFT) a pass/fail fit test to
assess the adequacy of respirator fit that relies on
the individual's response to the test agent.
Quantitative fit test (QNFT) an assessment of
the adequacy of respirator fit by numerically
calculating the amount of leakage into the
respirator.
Respiratory inlet covering the portion of a
respirator that forms the protective barrier
between the user's respiratory tract and an air-
purifying device or breathing air source, or both.
It may be a facepiece, helmet, hood, suit, or a
mouthpiece respirator with nose clamp.
Self-contained breathing apparatus (SCBA) an
atmosphere-supplying respirator for which the
breathing air source is designed to be carried by
the user.
Service life the time that a respirator, filter,
sorbent, or other respiratory equipment provides
adequate protection to the wearer.
Supplied-air respirator (SAR) or airline
respirator
an atmosphere-supplying respirator
for which the source of breathing air is not
designed to be carried by the user.
Tight-fitting facepiece a respiratory inlet
covering that forms a complete seal with the
face.
User seal check an action conducted by the
respirator user to determine if the respirator is
properly seated to the face.