Confined Space Entry Procedure: A Step-by-Step Walkthrough

This is a general sequence for a permit-required confined space entry under 29 CFR 1910.146. Your employer's written program and the specific permit control; construction work follows 1926 Subpart AA, which adds requirements such as continuous monitoring where possible.

1. Plan the job

• Identify the space and its hazards from the inventory and prior permits.
• Define the task, crew and duration.
• Assign roles: entry supervisor, attendant, authorized entrants, tester. Confirm each is trained.
• Confirm the rescue plan and that the rescue service is available.
• Coordinate with contractors or other employers working in or near the space.

2. Prepare and isolate

• Drain, depressurize, clean and flush as needed.
• Isolate lines by blanking, double block and bleed, or disconnecting.
• Lock out and tag out all energy sources and verify zero energy.
• Set barriers and signs to keep pedestrians and vehicles away.

See isolation and lockout.

3. Open safely and ventilate

• Eliminate conditions that make it unsafe to remove the cover (pressure, heat).
• Guard the opening once it's open.
• Set up forced-air ventilation from a clean source, with the duct reaching the work area, and purge. See ventilation.

4. Test the atmosphere

• Bump test and confirm calibration of the monitor.
• Test from outside, oxygen first, then flammables, then toxics, at the top, middle and bottom.
• Compare with acceptable entry conditions; record results, times and tester initials.
• Let entrants observe the testing.

5. Complete and authorize the permit

• Fill in every required element (space, purpose, duration, people, hazards, controls, conditions, tests, rescue, communications, equipment, other permits).
• The entry supervisor verifies by checking and signs the permit.
• Post the permit at the entry portal. Use our permit template.

6. Enter

• Entrants don PPE, personal monitors and harnesses connected to the retrieval system.
• The attendant logs each entrant in and stays outside.
• Confirm communication works before going deep into the space.

7. Monitor during entry

• Keep ventilation running and monitor continuously.
• The attendant watches conditions inside and outside, tracks entrants and orders evacuation for prohibited conditions, behavioral effects or outside hazards.
• The entry supervisor rechecks conditions at intervals and at any handoff.

8. Respond to emergencies

• Evacuate on any alarm, symptom or order.
• The attendant summons rescue and performs non-entry rescue with the retrieval system. Untrained people never enter to help.
• Provide SDS information to medical responders for any chemical exposure.

9. Close out

• Account for all entrants, tools and equipment.
• Close and secure the space; remove locks and blanks per the procedure, restoring the system safely.
• The entry supervisor cancels the permit, noting any problems.
• Keep the canceled permit at least 1 year for the annual program review.

Last reviewed: October 25, 2026 · Free general education based on OSHA 29 CFR 1910.146 and 29 CFR 1926 Subpart AA. It does not replace the site-specific training, written program and hands-on evaluation your employer must provide, and it does not issue a certificate. Nothing you enter on this page is saved or sent.