Confined Space Ventilation Check Checklist [FREE PDF]

Adequate ventilation is one of the most critical controls for permit-required confined spaces, as required by OSHA 29 CFR 1910.146 and reinforced by NFPA 350 and ANSI Z117.1. Improper or insufficient ventilation contributes to a majority of confined space fatalities due to oxygen deficiency, flammable atmospheres, or toxic gas buildup. This checklist ensures that mechanical ventilation is correctly sized, positioned, and verified through calibrated atmospheric monitoring before and during confin

Industry: General Industry
Frequency: Per Event
Estimated Time: 20-35 minutes
Role: Confined Space Entry Supervisor
Total Items: 37
Compliance: OSHA 29 CFR 1910.146(c)(5) - Permit-Required Confined Spaces, OSHA 29 CFR 1910.146(d)(5) - Atmospheric Testing Requirements, NFPA 350 (2021) Chapter 8 - Ventilation, ANSI Z117.1-2017 Section 7 - Atmospheric Testing and Ventilation, CSA Z1006-16 Section 8 - Atmospheric Hazards and Ventilation

Ventilation Equipment Pre-Check

Inspect all ventilation equipment before deployment to ensure it is serviceable, appropriately rated, and safe for the space hazards present.

Has the type of ventilation (forced air supply, exhaust, or combination) been selected based on the space's hazard profile?
Is the blower or fan unit rated for the atmospheric conditions present (spark-proof if flammable atmosphere is possible)?
Has the blower capacity (CFM) been verified as adequate for the volume of the confined space?
Is the blower unit free of visible damage, frayed cords, and mechanical defects?
Are ventilation ducting and hoses intact, properly sized, and free of kinks or obstructions?

Atmospheric Monitoring Equipment

Verify that all atmospheric monitors are calibrated, bump-tested, and appropriate for the hazards present in the space.

Has a calibrated, multi-gas monitor been selected that tests for oxygen, flammable gases (LEL), and relevant toxic gases (CO, H2S)?
Has the gas monitor been bump-tested or calibrated today prior to use?
Is the calibration date recorded and within the manufacturer's specified calibration interval?
Is a continuous gas monitoring device available to be worn by or positioned near the entrant during the entire operation?
Are alarm thresholds on the gas monitor set to OSHA-required action levels (O2: <19.5% or >23.5%, LEL: >10%, CO: >35 ppm, H2S: >10 ppm)?

Pre-Entry Atmospheric Testing

Record baseline atmospheric readings taken before ventilation and after ventilation to confirm the space is safe for entry.

Was initial atmospheric testing performed from outside the space before ventilation began?
Oxygen level reading AFTER ventilation (%O2):
Flammable gas / LEL reading AFTER ventilation (% LEL):
Carbon monoxide (CO) reading AFTER ventilation (ppm):
Hydrogen sulfide (H2S) reading AFTER ventilation (ppm):
Do all atmospheric readings meet acceptable entry criteria as recorded on the entry permit?

Ventilation Setup & Positioning

Verify that ventilation equipment is correctly positioned to ensure effective air exchange throughout the entire confined space.

Is the fresh air intake for the blower positioned upwind and away from potential contamination sources (vehicles, exhausts, chemical storage)?
Is the discharge duct directed to the lowest point of the space to displace heavier-than-air contaminants?
Is the exhaust opening positioned at the far end from the supply to maximize air circulation through the entire space?
Has the minimum purge time (to achieve 20 air changes) been calculated and observed before entry?
Is the ventilation equipment running continuously and will it remain running for the entire duration of the entry?

Continuous Monitoring During Entry

Establish procedures and verify equipment for continuous atmospheric monitoring while entrants are inside the space.

Is a continuous monitoring device deployed inside the space or worn by the entrant throughout the operation?
Has an alarm response procedure been established if the monitor detects out-of-range readings?
Is the attendant actively observing monitor readings and maintaining communication with the entrant?
Are atmospheric readings being recorded at defined intervals on the entry permit or monitoring log?
If the entrant moves to a new area within the space, is the monitor repositioned or checked in that area before work proceeds?

Ventilation Failure & Emergency Response Procedures

Confirm that procedures are in place to respond immediately if ventilation fails or atmospheric conditions deteriorate during entry.

Do all entrants know they must immediately exit the space if ventilation fails or an alarm activates?
Is a backup ventilation unit or additional blower available on-site in case of primary unit failure?
Has the attendant been instructed to order immediate evacuation if ventilation stops or monitor alarms sound?
Is emergency respiratory protection (SCBA or escape respirators) staged at the entry point for emergency use?
Are re-entry conditions clearly defined (what atmospheric levels must be confirmed before entrants return after ventilation failure)?

Post-Entry Ventilation Closeout

Document ventilation shutdown procedures and confirm the space is properly secured after entry operations are complete.

Have all entrants exited the space and been accounted for before ventilation equipment is shut down?
Has the entry permit been cancelled, signed, and retained per the 1-year record retention requirement?
Has the confined space been re-sealed, barricaded, or otherwise secured to prevent unauthorized entry?
Has all ventilation and monitoring equipment been cleaned, inspected for damage, and stored properly?
Have any deficiencies, near-misses, or lessons learned from this entry been documented for program review?
Provide any additional notes on ventilation performance, atmospheric readings, or deviations observed during this entry:

Related Confined Space Safety Checklists

Related Atmospheric Monitoring Checklists

Why Use This Confined Space Ventilation Check Checklist [FREE PDF]?

This confined space ventilation check checklist [free pdf] helps general industry teams maintain compliance and operational excellence. Designed for confined space entry supervisor professionals, this checklist covers 37 critical inspection points across 7 sections. Recommended frequency: per event.

Ensures compliance with OSHA 29 CFR 1910.146(c)(5) - Permit-Required Confined Spaces, OSHA 29 CFR 1910.146(d)(5) - Atmospheric Testing Requirements, NFPA 350 (2021) Chapter 8 - Ventilation, ANSI Z117.1-2017 Section 7 - Atmospheric Testing and Ventilation, CSA Z1006-16 Section 8 - Atmospheric Hazards and Ventilation. Regulatory-aligned for audit readiness and inspection documentation.

Frequently Asked Questions

What does the Confined Space Ventilation Check Checklist [FREE PDF] cover?

This checklist covers 37 inspection items across 7 sections: Ventilation Equipment Pre-Check, Atmospheric Monitoring Equipment, Pre-Entry Atmospheric Testing, Ventilation Setup & Positioning, Continuous Monitoring During Entry, Ventilation Failure & Emergency Response Procedures, Post-Entry Ventilation Closeout. It is designed for general industry operations and compliance.

How often should this checklist be completed?

This checklist should be completed per event. Each completion takes approximately 20-35 minutes.

Who should use this Confined Space Ventilation Check Checklist [FREE PDF]?

This checklist is designed for Confined Space Entry Supervisor professionals in the general industry industry. It can be used for self-assessments, team audits, and regulatory compliance documentation.

Can I download this checklist as a PDF?

Yes, this checklist is available as a free PDF download. You can also use it digitally in the POPProbe mobile app for real-time data capture, photo documentation, and automatic reporting.