Oregon Administrative Rules › Chapter 437 - DEPARTMENT OF CONSUMER AND BUSINESS SERVICES, OREGON OCCUPATIONAL SAFETY AND HEALTH DIVISION › Division 2 - GENERAL OCCUPATIONAL SAFETY AND HEALTH RULES › Section 437-002-2304 - Enclosed Spaces

Current through Register Vol. 63, No. 7, July 1, 2024
This rule covers enclosed spaces that may be entered by
				employees. It does not apply to vented vaults if the employer makes a
				determination that the ventilation system is operating to protect employees
				before they enter the space. This rule applies to routine entry into enclosed
				spaces in lieu of the confined space entry requirements contained in
				437-002-0146(4) through
				(11). If, after the employer takes the
				precautions given in 437-002-2304  and 437-002-2319  of Division 2/RR, the
				hazards remaining in the enclosed space endanger the life of an entrant or
				could interfere with an entrant's escape from the space, then entry into the
				enclosed space must meet the permit-space entry requirements of
				437-002-0146(4) through
				(11), Confined spaces, in Division 2/J.
(1) Safe work practices. The employer
			 must ensure the use of safe work practices for entry into, and work in,
			 enclosed spaces and for rescue of employees from such spaces.
(2) Training. Each employee who enters an
			 enclosed space or who serves as an attendant must be trained in the hazards of
			 enclosed-space entry, in enclosed-space entry procedures, and in enclosed-space
			 rescue procedures.
(3) Rescue
			 equipment. Employers must provide equipment to ensure the prompt and safe
			 rescue of employees from the enclosed space.
(4) Evaluating potential hazards. Before any
			 entrance cover to an enclosed space is removed, the employer must determine
			 whether it is safe to do so by checking for the presence of any atmospheric
			 pressure or temperature differences and by evaluating whether there might be a
			 hazardous atmosphere in the space. Any conditions making it unsafe to remove
			 the cover must be eliminated before the cover is removed.
Note
to paragraph (4): The determination called
				for in this paragraph may consist of a check of the conditions that might
				foreseeably be in the enclosed space. For example, the cover could be checked
				to see if it is hot and, if it is fastened in place, could be loosened
				gradually to release any residual pressure. An evaluation also needs to be made
				of whether conditions at the site could cause a hazardous atmosphere, such as
				an oxygen-deficient or flammable atmosphere, to develop within the
				space.
(5) Removing covers.
			 When covers are removed from enclosed spaces, the opening must be promptly
			 guarded by a railing, temporary cover, or other barrier designed to prevent an
			 accidental fall through the opening and to protect employees working in the
			 space from objects entering the space.
(6) Hazardous atmosphere. Employees may not
			 enter any enclosed space while it contains a hazardous atmosphere, unless the
			 entry conforms to the confined space standard, 437-002-0146  Confined spaces, in
			 Division 2/J.
(7) Attendants.
			 While work is being performed in the enclosed space, an attendant with
			 first-aid training must be immediately available outside the enclosed space to
			 provide assistance if a hazard exists because of traffic patterns in the area
			 of the opening used for entry. The attendant is not precluded from performing
			 other duties outside the enclosed space if these duties do not distract the
			 attendant from: monitoring employees within the space or ensuring that it is
			 safe for employees to enter and exit the space.
Note
to paragraph (7): See 437-002-2319 Underground electrical installations, for additional requirements on attendants
				for work in manholes and vaults.
(8) Calibration of test instruments. Test
			 instruments used to monitor atmospheres in enclosed spaces must be kept in
			 calibration and must have a minimum accuracy of ±10 percent.
(9) Testing for oxygen deficiency. Before an
			 employee enters an enclosed space, the atmosphere in the enclosed space must be
			 tested for oxygen deficiency with a direct-reading meter or similar instrument,
			 capable of collection and immediate analysis of data samples without the need
			 for offsite evaluation. If continuous forced-air ventilation is provided,
			 testing is not required provided that the procedures used ensure that employees
			 are not exposed to the hazards posed by oxygen deficiency.
(10) Testing for flammable gases and vapors.
			 Before an employee enters an enclosed space, the internal atmosphere must be
			 tested for flammable gases and vapors with a direct-reading meter or similar
			 instrument capable of collection and immediate analysis of data samples without
			 the need for off-site evaluation. This test must be performed after the oxygen
			 testing and ventilation required by paragraph (9) of this rule demonstrate that
			 there is sufficient oxygen to ensure the accuracy of the test for flammability.
(11) Ventilation and monitoring
			 for flammable gases or vapors. If flammable gases or vapors are detected or if
			 an oxygen deficiency is found, forced-air ventilation must be used to maintain
			 oxygen at a safe level and to prevent a hazardous concentration of flammable
			 gases and vapors from accumulating. A continuous monitoring program to ensure
			 that no increase in flammable gas or vapor concentration above safe levels
			 occurs may be followed in lieu of ventilation if flammable gases or vapors are
			 initially detected at safe levels.
Note
to paragraph (11): See the definition of
				"hazardous atmosphere" for guidance in determining whether a specific
				concentration of a substance is hazardous.
(12) Specific ventilation requirements. If
			 continuous forced-air ventilation is used, it must begin before entry is made
			 and must be maintained long enough for the employer to be able to demonstrate
			 that a safe atmosphere exists before employees are allowed to enter the work
			 area. The forced-air ventilation must be so directed as to ventilate the
			 immediate area where employees are present within the enclosed space and must
			 continue until all employees leave the enclosed space.
(13) Air supply. The air supply for the
			 continuous forced-air ventilation must be from a clean source and may not
			 increase the hazards in the enclosed space.
(14) Open flames. If open flames are used in
			 enclosed spaces, a test for flammable gases and vapors must be made immediately
			 before the open flame device is used and at least once per hour while the
			 device is used in the space. Testing must be conducted more frequently if
			 conditions present in the enclosed space indicate that once per hour is
			 insufficient to detect hazardous accumulations of flammable gases or vapors.
Note
to paragraph (14): See the definition of
				"hazardous atmosphere" for guidance in determining whether a specific
				concentration of a substance is hazardous.
Note
to 437-002-2304: Entries into enclosed
				spaces conducted in accordance with the requirements of 437-002-0146 (4)
				through (11), Confined spaces, are considered as complying with 437-002-2304  of
				Division 2/RR.
Stat. Auth.: ORS
				  654.025(2)
				  & 656.726(4)
Stats. Implemented: ORS
				  654.001 -
				  654.295