Confined Spaces – The Nuts and Bolts

• September 17, 2021
• magda

By Daniel Green

It’s 4.15pm on a Friday arvo. You’re wheeling your toolbox back through the maze of passageways on this site so you can chuck it in the ute and bugger off. Knock off beers started 15 minutes ago and you’ve gotten a string of picture messages of icy cold ones from your mates. It’s 300m to the ute if you follow the umpteen twists and turns in this tired old place. You’re pretty beat. Thirsty. Over it. And then you notice the short 30m tunnel nearby that leads to the site car park. It’s dark inside but you can see the light at the other end. You can even see your ute. It’s so close! Except a sign hangs across the opening: CONFINED SPACE – ENTRY BY PERMIT ONLY. You can almost taste the first sip of beer as you walk towards the tunnel. She’ll be right, right?

Or here’s one. You’re out on a job site – a petroleum refinery undergoing some remedial works. You’re walking along, minding your own business. As you pass a massive, brand new diesel tank you hear the faint sound of someone crying out. You look around but there’s only one place it could be coming from. You climb to the top of the tank and lift the hatch to find one of your mates. He’s fallen to the floor, his femur is sticking out of his thigh and he’s bleeding pretty hard. You look down at your phone but there’s no phone service. You tell him everything will be okay and start to climb down to him..

Confined Defined Space

If you ask Wikipedia [the source of all things good and true], a confined space is a space with limited entry and egress and is not suitable for human inhabitants. dictionary.com is pretty much the same. The leading cause of confined space deaths over the last fifteen years is a lack of training. Probably makes sense that our governing bodies have made it worthy of a ticket.

What the Actual Is Even One?

So what makes a confined space? SafeWork NSW is the authority on safety in construction & other national industries. They reckon the following definitely are:

• Vats and tanks
• Pits and pipes
• Ducts, flues and chimneys
• Silos and shafts
• Pressure vessels
• Underground sewers
• Wells [wet or dry]
• Shipboard spaces
• Void spaces
• Other similarly enclosed/partially enclosed structures

They reckon the following definitely aren’t:

• Mine shafts or the workings of a mine
• Places intended for human occupancy
• Some enclosed or partially enclosed spaces that have harmful contaminants but have been designed for a person to occupy, for example abrasive blasting or spray-painting booths
• Enclosed or partially enclosed spaces that are designed to be occasionally occupied by a person, for example a fumigated shipping container or a coolroom/chiller/freezer

Dukes of Hazzard

There’s obvious dangers associated with working in and around confined spaces. There’s also less obvious ones we may never have considered:

• Toxic Atmosphere
  • This may cause various acute effects, including impairment of judgement, unconsciousness and death. A toxic atmosphere may occur due to the presence or ingress of hazardous substances. These substances may be present in the confined space for various reasons such as:
    • remaining materials from previous processing or storage
    • substances arising from the disturbance of sludge and other deposits
    • the presence of a fire or flames within the space
    • seepage from improperly isolated adjoining plant
    • substances formation during the work processes carried out in the space
    • substances being released from under building materials as a result of the work process
      
      
• Oxygen Deficiency
  • Oxygen can be lacking a confined space for the following reasons:
    • displacement of air by another gas
    • various biological processes or chemical reactions (such as rotting of organic matter, rusting of metals, burning, etc)
    • absorption of air onto steel surfaces, especially where these are damp
      
      
• Oxygen Enrichment
  • An excess of oxygen, in the presence of combustible materials, results in an increased risk of fire and explosion. Some materials, which do not burn in air, may burn vigorously or even spontaneously in an enriched oxygen atmosphere.
    
    
• Flammable or Explosive Atmospheres
  • A flammable atmosphere presents a risk of fire or explosion. Such an atmosphere can arise from the presence in the confined space of flammable liquids or gases or of a suspension of combustible dust in air. If a flammable atmosphere inside a confined space ignites, an explosion may occur, resulting in the expulsion of hot gases and the disintegration of the structure.
    
    
• Flowing Liquid or Free Flowing Solids
  • Liquids or solids can flow into the confined space causing drowning, suffocation, burns and other injuries. Solids in powder form may also be disturbed in a confined space resulting in an asphyxiating atmosphere.
    
    
• Excessive Heat
  • The enclosed nature of a confined space can increase the risk of heat stroke or collapse from heat stress, if conditions are excessively hot. The risk may be exacerbated by the wearing of personal protective equipment or by lack of ventilation

Tickets on Yourself

When it comes to courses – confined space training ain’t just confined space training. There’s three tiers, each with a different use.

Confined Space Training – Basic

This is the most entry level qualification you can obtain. As the title suggests it gives you the skills and knowledge to enter a confined space, do your work [dependent on what it is] and of course leave the space in the same condition you entered it in. With units around hazard analysis, planning and preparation, the confined space work itself, exiting and clean up – this is an ideal qualification for someone looking for an inexpensive course that will furnish them with a good knowledge base for working in and around confined spaces. It is a one day training package.

Units:

MSMWHS201      Conduct hazard analysis
RIIWHS202E       Enter and work in confined spaces
MSMPER205       Enter confined space
MSMPER200      Work in accordance with an issued permit

Confined Space Training – Intermediate

If you’ve held had your basic training for a while now, or you just want to get more into the bones of Confined Space training then you might enjoy a more detailed course in Gas Testing and Issuing Permits. The primary difference is that in basic training you are subject to the terms of work, whereas at the intermediate level you’re creating them. So instead of working under a permit issued by someone – you’re issuing the permit. In addition to the four units you get during basic, you get another three – one of which is CPR. As you climb the Confined Space training ladder you might notice you’re given more power, more responsibility and more decision making ability. This training takes two days.

MSMWHS217       Gas test atmospheres
MSMPER300       Issue work permit
HLTAID009          Provide Cardiopulmonary Resuscitation

Confined Space Training – Advanced

This is the most badass of all the training and that’s Confined Space Rescue. As you’ve probably guessed, this course allows you to rescue workers trapped in confined space situations. It is the most extensive training and gives you the most seniority in a confined space situation. It is a full three day course that gives an additional three units on top of the seven you already have. This is a three day course by itself, meaning you’ve now completed six full days of training just in the realm of confined spaces.

MSMWHS216      Operate breathing apparatus
PUASAR025        Undertake confined space rescue
MSMPER202       Observe permit work

Refined Space Knowledge

So there you have it. Hopefully now you have a better understanding of what makes a confined space, what the hazards are and how to get trained so you definitely make it to those knock off beers!