Maintenance of safe conditions

Under 1915.15(a) you must disconnect, blank off, or otherwise block pipelines by a positive method so hazardous materials cannot be discharged into the certified space. Employers must use physical measures (for example, disconnecting lines, installing blind flanges or positive blanks) rather than relying solely on procedural controls.

• See the Preventing hazardous materials from entering requirement in 1915.15(a) for the exact wording.
• Related testing and certification requirements are in 1915.12, 1915.13, and 1915.14.

(These measures are mandatory whenever a pipeline could carry hazardous materials into a certified space.)

Under 1915.15(b) you must stop work immediately when a change occurs that could alter conditions within a tested confined or enclosed space or other dangerous atmosphere, and you may not resume until the area is visually inspected and retested and found to comply with the applicable standards.

• Examples include opening manholes, adjusting valves that regulate hazardous material flow, or other actions that could introduce hazards; see Alteration of existing conditions, 1915.15(b).
• Retesting must verify compliance with 1915.12, 1915.13, and 1915.14 as applicable.

Under 1915.15(c) a competent person must visually inspect and test each space certified “Safe for Workers” or “Safe for Hot Work” as often as necessary to ensure atmospheric conditions remain within those established by the certificate.

• The frequency is risk-based: test and inspect whenever conditions or work activities could change atmospheric safety.
• See Tests to maintain the conditions of a Marine Chemist's or Coast Guard authorized person's certificates, 1915.15(c).
• The competent person must follow the testing criteria in 1915.12, 1915.13, and 1915.14.

Under 1915.15(d) work in the certified space must be stopped and may not resume until a Marine Chemist or Coast Guard authorized person retests the space and issues a new certificate under 1915.14(a).

• See Change in the conditions of a Marine Chemist's or Coast Guard authorized person's certificate, 1915.15(d).
• The retesting and new certificate must meet the procedures in 1915.14(a) and the testing rules in 1915.12–1915.14.

Yes. Under 1915.15(e) a competent person must continue to test and visually inspect the space as often as necessary after initially determining it is safe for entry to ensure atmospheric conditions are maintained.

• See Tests to maintain a competent person's findings, 1915.15(e).
• Continue monitoring per the applicable testing protocols in 1915.12, 1915.13, and 1915.14.

Under 1915.15(f) work must be stopped immediately until the tested space's conditions are corrected to comply with [1915.12, 1915.13, and 1915.14], as applicable.

• See Changes in conditions determined by competent person's findings, 1915.15(f).
• After correction, retesting and re-inspection must follow the applicable procedures in 1915.12–1915.14.

Under 1915.15, you must use the testing and entry criteria set out in 1915.12, 1915.13, and 1915.14 when retesting or inspecting confined/enclosed spaces and other dangerous atmospheres.

• These sections describe hazards, required tests, and certification procedures that apply before work may begin or resume.
• See 1915.12, 1915.13, and 1915.14 for details.

Under 1915.15(c) and (e) a "competent person" must perform the ongoing visual inspections and tests to ensure conditions are maintained.

• The shipyard standards define a competent person and require that person to be capable of recognizing and evaluating hazardous atmospheres and specifying necessary protections; see OSHA's interpretation on Competent person requirements in shipyards.
• For certified spaces, a Marine Chemist or Coast Guard authorized person issues certificates but the competent person must still inspect and test spaces as required by 1915.15(c) and 1915.15(e).

No. If a competent person finds that atmospheric conditions in a space certified by a Marine Chemist or Coast Guard authorized person no longer meet the requirements, work — including hot work — must stop and may not resume until the space is retested and a new certificate is issued by a Marine Chemist or Coast Guard authorized person under 1915.14(a), as required by 1915.15(d).

• See 1915.15(d) and 1915.14(a).
• A competent person can and must stop work per 1915.15(f) but cannot reauthorize certified hot work without the Marine Chemist/Coast Guard retest and certificate.

Under 1915.15(a) temporary measures may be acceptable only if they provide a positive method to prevent discharge (for example, disconnecting or blanking off); simply closing a single valve is not necessarily sufficient unless it provides a positive block.

• The rule requires pipelines that could carry hazardous materials to be "disconnected, blanked off, or otherwise blocked by a positive method," see 1915.15(a).
• When in doubt, use a physical positive barrier (e.g., blind flange or double block-and-bleed) consistent with the standard to ensure there is no discharge into the space.

Yes. 1915.15(b) requires stopping work when a change occurs that could alter conditions within a tested confined or enclosed space; opening a manhole or other closure is explicitly listed as an example and therefore warrants stopping work until the space is inspected and retested.

• See Alteration of existing conditions, 1915.15(b).
• After stopping work, conduct visual inspection and retesting per 1915.12–1915.14 before resuming.

When a competent person inspects a space under 1915.15 they must perform the visual inspections and atmospheric tests required by 1915.12, 1915.13, and 1915.14, including checks for flammable vapors, toxic atmospheres, and oxygen levels as applicable.

• The specific instruments, tests, and pass/fail criteria are described in 1915.12–1915.14.
• If the space is originally certified by a Marine Chemist, the competent person must still monitor conditions as required by 1915.15(c).

Yes. While 1915.15 requires testing and inspections, a competent person may specify necessary protections for hazardous exposures even when there is no OSHA PEL, provided they meet the definition and responsibilities of a competent person under Part 1915.

• OSHA's interpretation on Competent person requirements in shipyards explains that a competent person must be capable of recognizing and evaluating hazardous exposures and specifying necessary protections when no PEL exists.
• Maintain inspections and testing as required by 1915.15(c) and 1915.15(e).

It depends: if the space was previously certified by a Marine Chemist or Coast Guard authorized person and their certificate was invalidated by the change, a Marine Chemist or Coast Guard authorized person must retest and issue a new certificate before reopening per 1915.15(d). For spaces initially judged safe by a competent person (not Marine Chemist-certified), the competent person must correct and re-test and may resume work only when the space meets the applicable requirements in [1915.12–1915.14], per 1915.15(f) and 1915.15(e).

• See 1915.15(d), 1915.15(e), and 1915.15(f).
• Retesting procedures for Marine Chemist certificates are in 1915.14(a).

Section 1915.15 requires competent persons to visually inspect and test spaces "as often as necessary," but it does not prescribe a specific documentation format in this paragraph; nonetheless, employers should maintain clear records of inspections and tests to show compliance with [1915.12–1915.14] and to demonstrate that monitoring occurred as required.

• See the inspection and testing duties in 1915.15(c) and (e).
• Documentation best practices are consistent with the responsibilities of a competent person described in OSHA's Competent person requirements in shipyards interpretation.

Under 1915.15, any finding by a competent person that atmospheric conditions fail to meet the applicable requirements requires stopping work; if the space was Marine Chemist- or Coast Guard-certified, you must stop work and obtain retesting and a new certificate from a Marine Chemist or Coast Guard authorized person per 1915.15(d).

• See 1915.15(d) and 1915.15(f).
• If the space was declared safe by a competent person (not Marine Chemist-certified), correct the condition and re-test per 1915.15(f).

Under 1915.15, a Marine Chemist or Coast Guard authorized person issues a certificate declaring a space "Safe for Workers" or "Safe for Hot Work," but a competent person must continue visual inspections and testing to ensure conditions remain within the certificate's requirements; if a competent person detects a failure, work must stop and the Marine Chemist must retest and reissue the certificate per 1915.15(c) and (d).

• See 1915.15(c) and 1915.15(d).
• Retesting and certification procedures are in 1915.14(a).

No. Even when a Marine Chemist has issued a certificate, 1915.15(c) requires a competent person to visually inspect and test the space as often as necessary to ensure the certificate conditions are maintained; reliance on a certificate alone without ongoing checks is not sufficient.

• See 1915.15(c).
• Any change detected that affects conditions must be handled per 1915.15(b)–(d).

Under 1915.15, if a competent person finds atmospheric conditions that do not clearly meet the applicable requirements, they must stop work if the conditions fail to meet the standards; because 1915.15(c),(e),(f) require testing "as often as necessary," conservative action (stop, correct, and retest) is appropriate when readings are questionable.

• See 1915.15(e) and 1915.15(f).
• The competent person must ensure the space meets the criteria in 1915.12–1915.14 before resuming work.

Under 1915.15, the competent person is responsible for inspecting and testing the space and must stop work if they find a leak or unsafe atmosphere; if the space had been Marine Chemist-certified and the certificate is affected, a Marine Chemist or Coast Guard authorized person must retest and issue a new certificate before work resumes per 1915.15(d). For other competent-person-controlled spaces, work can only resume after correction and retesting show compliance with [1915.12–1915.14], per 1915.15(f).

• See 1915.15(c)–(f).
• OSHA's Competent person requirements in shipyards interpretation explains the competent person's role in specifying necessary protections.

Under 1915.15(b), opening or adjusting closures or valves that could alter the atmosphere requires stopping work and retesting; if the space was originally certified by a Marine Chemist or Coast Guard authorized person, a retest by that authorized person and a new certificate under 1915.14(a) will be required before resuming work per 1915.15(d).

• See the example and requirement in 1915.15(b) and the retest/certificate rule at 1915.15(d).