OSHA answers FAQs for confined space compliance in construction

What is a confined space?

A confined space means a space that (1) is large enough and so configured that an employee can bodily enter it; (2) has limited or restricted means for entry and exit; and (3) is not designed for continuous employee occupancy (see 29 C.F.R. 1926.1202). All three criteria must be met in order for a space to be considered a confined space and covered by the Confined Spaces in Construction Standard (hereinafter “Confined Spaces in Construction Standard” or “Standard”).

What is a permit-required confined space?

A permit-required confined space or permit space means a confined space that has one or more of the following characteristics: (1) contains or has the potential to contain a hazardous atmosphere; (2) contains a material that has the potential for engulfing an entrant; (3) has an internal configuration such that an entrant could be trapped or asphyxiated by inwardly converging walls or by a floor which slopes downward and tapers to a smaller cross-section; or (4) contains any other recognized serious safety or health hazard (see 1926.1202).

Paragraph 1926.1203(a) requires that each employer ensure that a competent person identifies all confined spaces in which one or more of the employees it directs may work, and identifies each space that is a permit space, through consideration and evaluation of the elements of that space, including testing as necessary. If the competent person must enter the space to assess its characteristics and potential hazards, must the competent person treat the space as a permit-required confined space?

If the competent person can reasonably foresee the presence of a hazard or potential hazard that would make the space a permit-required confined space (see response to Question 2), the competent person must treat the space as a permit-required confined space when entering the space to assess it. However, if the competent person cannot reasonably foresee the presence of such a hazard, the competent person would not need to treat the space as a permit-required confined space when entering the space to assess it. Of course, if the competent person encounters such a hazard when assessing the space, whether or not the hazard was reasonably foreseeable, the competent person must treat the space as a permit-required space after identifying the hazard.

Does the standard impose additional requirements on “permit-required confined spaces” beyond those imposed for “confined spaces”?

Yes. In fact, the vast majority of the standard’s requirements only apply to permit-required confined spaces, and attics, basements, and crawl spaces in a residential home will not typically trigger these requirements. Once the employer’s competent person performs an initial evaluation and determines that a confined space does not require a permit (1926.1203(a)), the employer’s only further obligations under the standard are to have a competent person reevaluate the space and, if necessary, reclassify it as a permit-required confined space if changes in the use or configuration of the space occur that could increase the hazards or potential hazards to entrants or if the employer has any indication that the initial evaluation may have been inadequate (1926.1203(f)).

If the employer’s competent person determines that the space is a permit-required confined space, the following provisions also apply: entry communication and coordination (1926.1203(h)), permit-required confined space program (1926.1204), permitting process (1926.1205), entry permit (1926.1206), training (1926.1207), duties of authorized entrants, attendants, and entry supervisors (1926.1208-1210), and rescue and emergency services (1926.1211).

Does the characteristic “contains or has the potential to contain a hazardous atmosphere” in the definition of “permit-required confined space” refer only to those atmospheres which pose an acute hazard?

Yes. Where employees are exposed to hazardous atmospheres that do not present an immediate danger of death or impairment that could impede the employee’s ability to exit the confined space without assistance, OSHA’s health standards for those hazards apply, rather than the Confined Spaces in Construction Standard (see 1926.1202 definition of “hazardous atmosphere”).

In some residential home building projects, the home builder constructs multiple homes with the same or similar basic configuration. If the presence or absence of any potential hazard in an attic, crawl space, or basement is known, does the standard require a competent person to examine each attic, crawl space, or basement in each home to make a determination as to whether the space is a permit-required confined space?

No. The standard requires a competent person to identify all permit-required confined spaces in which employees may work “through consideration and evaluation of the elements of that space, including testing as necessary.” 1926.1203(a). If a competent person can reliably determine whether attics, crawl spaces, or basements with the same or similar configuration contain one of the hazards or potential hazards listed in response to Question 2 without physically inspecting each of the spaces, the competent person need not physically examine each space to make the identification required under 1926.1203(a).