In addition to, and not in lieu of
29 CFR
1910.94, the following rules pertaining to
ventilation apply in Oregon:
(1)
Definitions:
(a) "Administrative Control"
means the reduction of employee exposure to physical or chemical agents by
control of the time of exposure to some period less than eight hours in
length;
(b) "Harmful" or
"Hazardous" as applied to the health effects of dusts, fumes, vapors, mists,
gases, or any environmental condition, means any mechanical, infectious, toxic,
or other action which is likely to produce medically determined injury or
disease of exposed workers;
(c)
"Health Hazard Control Measure" means the equipment or working arrangements
designed to prevent the exposure of employees to harmful or hazardous
situations. Such control measures may include, but are not limited to:
(A) Ventilation systems;
(B) Energy absorption system;
(C) Personal protective equipment;
(D) Air contaminant monitoring; and
(E) Human biological monitoring.
(d) "Local Exhaust System" means a
system of hoods, booths, or enclosures designed to remove contaminants at
points of generation or release into the atmosphere connected by means of
piping to airflow or suction producing equipment;
(e) "Occupational Health Hazard" means those
materials, processes, and atmospheric contaminants or energy concentrations
which during normal or abnormal working conditions are likely to result in
injury or illness to the unprotected employee;
(f) "Ventilation, Dilution" means ventilation
provided to dilute the concentration of atmospheric contaminants in the
atmosphere in all or part of the place of employment;
(g) "Ventilation, General" means the
provision of fresh air at the place of employment;
(h) "Ventilation, Local Exhaust" means that
the type of ventilation in which suction is applied at the point of generation
or release of atmospheric contaminants;
(i) "Ventilation, Natural" means ventilation
designed to depend wholly upon relative air density, and includes the use of
openable doors, windows, and other building apertures.
(2) Recirculation. No air from any local
exhaust system shall be recirculated, unless:
(a) The inert dust contained therein has a
Permissible Exposure Limit (PEL) equal to or greater than ten milligrams per
cubic meter as listed in Tables Z-1, Z-2, or Z-3 in OAR Chapter 437, Division
2, Subdivision Z, 1910, OAR
437-002-0382, Oregon Rules for
Air Contaminants. The inert dust concentration in such recirculated air shall
not exceed five milligrams per cubic meter; or
(b) The contaminant contained therein has a
Permissible Exposure Limit (PEL) equal to or greater than 100 parts per million
as listed in Tables Z-1, Z-2, or Z-3 or OAR Chapter 437, Division 2,
Subdivision Z, OAR
437-002-0382, Oregon Rules for
Air Contaminants. The contaminant concentration in such recirculated air shall
not exceed 25 percent of its PEL; or
(c) The concentrations of contaminants in
recirculated air do not exceed 25 percent of unity as calculated by the formula
given in Division 2, Subdivision Z, OAR
437-002-0382(4)(b),
Oregon Rules for Air Contaminants.
(3) Make-Up Air. Outside air equal in amount
to the air removed by local exhaust systems shall be provided to replace air
removed by an exhaust ventilation system.
(4) Air Contamination from Exhaust System.
The discharge from any exhaust system shall be such that no air contamination
therefrom will enter any window, door, or other opening of any work area in
quantities sufficient to create a harmful or hazardous work
atmosphere.
(5) Use of Salamanders
and Fuel-Burning Heating Devices. Salamanders and other fuel-burning heating
devices shall not be used in enclosed or inadequately ventilated spaces in
which workers are employed unless such heating device is provided with a proper
pipe, chimney, or enclosure to carry hazardous gases to the outside
atmosphere.
(6) Local Exhaust
Ventilation. The capacity of a local exhaust system shall be calculated on the
basis of all hoods, booths, and enclosures connected to the system being open,
except where the system is so interlocked that only a portion of it can be
operated at a given time, in which case the capacity shall be calculated on the
basis that all the hoods in the group requiring the greatest volume rate of
exhaust are open.
(7) Exhausting
More Than One Substance. Two or more operations involving more than one
substance shall not be connected to the same exhaust system when a combination
of the substances removed may constitute a fire hazard, or otherwise dangerous
mixture.
(8) Exhausting Materials
with Flammable Properties. Those processes or operations which require local
exhaust ventilation and generate materials with flammable properties shall be
protected from sources of ignition.
(9) Removal of Collected Materials. Collected
materials shall be removed when necessary so as to maintain effective operation
of the local exhaust system at all times.
(10) Disposal of Collected Materials.
Collected materials shall be disposed of in a manner which will not result in a
hazard.
(11) Requirements for
Reduction of Air Contaminant Concentrations. A local exhaust system shall be in
operation until all contaminants are reduced to concentrations at or below the
Threshold Limit Values when any person is at risk.
NOTE: 1910.94
(a)(6) was NOT adopted by OR-OSHA. In Oregon,
OAR
437-002-0081(12)
(which references a more current ANSI
standard) applies.)
(12)
Air supply and air compressors. The air for abrasive-blasting respirators shall
be free of harmful quantities of dusts, mists, or noxious gases, and shall meet
the requirements for air purity set forth in ANSI Z9.2-1979, Fundamentals
Governing the Design and Operation of Local Exhaust Systems. The air from the
regular compressed air line of the plant may be used for the abrasive-blasting
respirator if:
(a) A trap and carbon filter
are installed and regularly maintained to remove oil, water, scale, and odor;
(b) A pressure reducing diaphragm
or valve is installed to reduce the pressure down to requirements of the
particular type of abrasive-blasting respirator; and
(c) An automatic control is provided to
either sound an alarm or shut down the compressor in case of overheating.
NOTE: Oregon did not adopt 1910.94(a)(6), which
references an outdated ANSI standard. Instead, the following Oregon-initiated
rule applies. This rule is identical, except that the current ANSI standard is
referenced.
(13)
Blasting Nozzles. In addition to and not in lieu of the provisions of
1910.94(a)(7), blasting nozzles shall be equipped with a deadman switch or
other effective means to prevent hose and nozzle from whipping. A support shall
be provided on which the nozzle may be mounted when not in
use.