Confined Space Entry

A worker climbs into a tank to do a quick patch and drops without a sound. His buddy sees him down and goes in after him — and drops too. That second death is the one that keeps happening, because the air that killed the first worker is still there and it looks and smells exactly like clean air. This is the talk we have before anyone opens a hatch.

The hazard

A confined space has a specific meaning: fully or partly enclosed, not built for someone to work in continuously, and capable of holding an atmospheric hazard — tanks, vaults, manholes, pits, sewers, wet wells, large pipes. The danger is the air. It can be short of oxygen, full of toxic gas like hydrogen sulphide or carbon monoxide, or holding enough flammable vapour to explode, and you can't see, smell, or feel any of that before it puts you down. On top of the air, loose material can shift and bury you, or water can flood the space fast.

In Ontario this work is governed by O. Reg. 632/05: the employer must have a written program, assess the hazards, build a plan for each space, train the workers, run an entry-permit system, and have rescue procedures in place. Every line on that permit is a step that keeps the person inside alive, and it only works if the crew runs it the same way every single time.

What to do

• No permit, no entry — no exceptions. Nobody goes in without a completed permit and a plan for that specific space. The "it'll only take a second" entry is the one nobody tested.
• Isolate and lock out everything that feeds in. Any line, machine, auger, valve, or flow that could deliver product, energy, or water while someone's inside.
• Ventilate before and during. Move fresh air through before entry and keep it moving while the work goes on.
• Test before entry, and keep testing as the plan requires. Check oxygen, toxic gas, and flammable gas before anyone enters. How often you re-test, and whether monitoring runs continuously, comes from the plan for that space — a job that stirs up sludge or burns oxygen needs continuous monitoring; the plan is what decides. Oxygen has to sit between 19.5% and 23% by volume: too little and you go down, too much and things ignite easily and burn violently, clothing included.
• Rescue is arranged before entry, not improvised after. Adequate written rescue procedures, trained rescue personnel and their equipment immediately available, and everyone briefed on their part. Where the assessment makes it workable, set up for non-entry retrieval — a harness and retrieval line so someone can be pulled out from outside. Where retrieval isn't suitable — an obstructed space, entanglement risk — the plan has to say what happens instead, and that has to be real before the hatch opens.
• Station a trained attendant who never enters. Someone stays outside the whole time, in constant contact with the worker inside, watching for trouble. If it goes wrong, the attendant raises the alarm and starts the rescue plan. The attendant does not go in.

Watch out for

• The instinct to go in after a downed worker. That instinct is what kills the second and third person. Call for help, hit the rescue plan, pull from outside.
• Air that "seems fine." Toxic and oxygen-poor air give no warning at all. The monitor knows; your senses don't.
• A space that was safe yesterday. Familiar doesn't mean safe — test it fresh every entry.
• A permit filled in from memory at the tailgate rather than from the space in front of you.

Talk it over

• Which spaces on this site count as confined, and who is actually trained and authorized to enter them?
• If someone went down inside right now: who's calling, who's on the retrieval line, and who is definitely not going in?
• For today's space — what does the plan say about how often we re-test?