Confined Space Toolbox Talk

The talk, read this out

Nobody goes into anything today that you have to climb into and cannot walk straight out of, until we have had this conversation. That includes the vault, the manhole and the crawlspace.

A confined space is three things at once: big enough to get into and work, not designed for people to stay in, and with a way in or out that is restricted. A trench with a ramp is not one. A vault with a ladder is.

It becomes a permit space when it also has one of four problems: a hazardous atmosphere, material that could swallow you, walls or a floor that slope to a smaller cross section, or any other serious hazard inside.

Hazardous atmosphere has numbers and you should know them. Oxygen below 19.5 percent or above 23.5 percent. Flammable gas or vapor above 10 percent of its lower flammable limit. Combustible dust thick enough that you cannot see five feet.

You cannot detect any of that. Oxygen displacement gives no warning at all, and the first symptom of the atmosphere that kills you is that you stop being able to decide to leave.

So the space gets tested before entry and monitored while people are in it, it gets ventilated, and somebody stays outside the whole time doing nothing else. That attendant is not helping and not fetching. His job is to stay at the hole and count the people in it.

The part everybody has to hear is the rescue part. If a man goes down inside, you do not go in. Rescue from a permit space is done by people with air on their backs and a retrieval line, and the reason that rule exists is a list of second bodies.

Point at these before anybody starts

A talk delivered in a trailer is a meeting. Stand where the work is and put a hand on each of these.

• Every space on this site you would have to climb into. Name them out loud.
• The entry point, and how a person on a stretcher would come back out of it.
• The gas monitor, and when it was last bump tested.
• The blower and the ducting, and where its intake is drawing air from.
• Where the attendant stands, and what he is holding.
• The permit sign, and whether anything on this site is posted.

The rules that apply

• Before work starts, a competent person identifies every confined space on the site and decides which of them are permit spaces.
• Permit spaces are posted with danger signs, and the controlling contractor and the other employers on site are told where they are.
• Anyone who is not authorized to enter a permit space must be effectively prevented from entering it.
• If employees are going in, there is a written permit space program on the site, available for inspection before and during entry.
• The atmosphere is tested and monitored: oxygen between 19.5 and 23.5 percent, flammable gas or vapor below 10 percent of its lower flammable limit, and no contaminant above its exposure limit.
• Nobody enters to rescue. Rescue is done by the trained, equipped rescuers named in the permit, and entrants are on a retrieval system where one can be used.

Ask the crew

Three questions, answered out loud by name. This is the part that tells you whether anybody was listening.

• Which spaces on this job are confined spaces, and which of those need a permit?
• What does the attendant do if you stop answering him?
• What happens if you see somebody collapse inside?

Close with this

The space that killed the first man is still exactly as dangerous when the second one climbs in.

Questions people ask

Is a trench a confined space?

Usually not, and it has its own standard in subpart P. A trench becomes a confined space problem when the entry and exit is restricted or when an atmosphere collects in it, which happens in deep trenches and where exhaust, sewer gas or heavier than air vapors can settle.

Can we skip the permit if we ventilate?

There is a narrow alternate procedure for that, and its conditions are strict: every physical hazard eliminated or isolated, continuous forced air ventilation proved sufficient on its own, entrants able to get out safely if it stops, and the supporting data documented. It is not a shortcut, it is a different set of paperwork.

Who can be the attendant?

Someone trained for that role who stays outside and does nothing else for the whole entry. The moment the attendant walks off to get a tool, the entry has stopped complying and the person inside has nobody.

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