CONFINED SPACES: MORE THAN MEETS THE EYE

Many people can encounter work in confined spaces – from servicing pumps at petrol stations to performing maintenance on grain silos. Being able to correctly identify a space as “confined” is the first and most important first step in working safely. 
 
Interestingly, confined spaces are not strictly defined by their size – in fact, not all confined spaces are small. They can also be enclosed or partially enclosed, above or below ground.
 
“What matters are the hazards that exist, and the work that people are doing,” explains Michael Forrest, Trainer and Assessor, Coates Hire Training Services. “These factors can quickly turn an innocent looking trench into a confined space with a toxic atmosphere.”
 
Spot the hazards
 
Three major hazards encountered in confined spaces include:
 
1. Engulfment
 
Because so many environments are considered confined spaces, there are also many scenarios that could lead to engulfment (in other words, being plunged into or immersed by something). Some common examples include grain or cattle feed engulfing workers inside a silo, or water flooding into a storm drain – both of which present a considerable risk to someone working in that environment.
 
2. Hazardous atmospheres
 
Poor ventilation can allow hazardous atmospheres to quickly develop, causing loss of consciousness, impairment, injury or death.
 

Atmospheric oxygen concentrations below 19.5% (oxygen deficiency), or above 23.5% (oxygen enrichment), are considered hazardous.

 

Carbon monoxide (CO) is one of the more common hazardous gases found in and around confined spaces. According to Safe Work SA, if ventilation is reduced or the rate or duration of CO production increases, normally safe environments can become extremely hazardous.

 

Many people aren’t aware of just how dangerous hydrogen sulphide (H2S) can be. This deadly gas – often produced by rotting vegetable mass – is commonly found in low-lying areas like sewers; manure pits; water, oil and gas wells and underground telephone vaults.

 
Hazardous atmospheres are not always obvious or easy to detect. Some gases don’t exist naturally, but are triggered by the use of cleaning products. Other non-hazardous gasses can be flammable when ignition sources like power tools are introduced.
 
Gas detection equipment can be used to assess hazardous atmospheres, and when known gas hazards exist, gas masks, portable ventilation units and breathable air solutions can be implemented.
 
3. Changing conditions
 
Hazards can quickly emerge when conditions change. Consider how dangerous the recent flash storms that thrashed Sydney would be if you were working in a stormwater drain at the time! New or changing working environments can also present considerable risks for people working in confined spaces.
 
Two-way radios help to maintain communication for relaying important safety information (like updates on weather and other changing conditions), and for seeking assistance when required.
 
Intrinsically safe two-way radios are safe to use in hazardous environments like confined spaces, to maintain communication and seek assistance if required.
 
Working safely
 
Risk assessments
 
Once confined spaces have been identified, risk assessments are vital to working safely in these environments. Safe Work Australia offers these pointers on assessing risk in confined spaces.
 

What are your contingencies for rescue if access and regress points become blocked?

Are all workers entering the confined space competent?

Can normal atmospheric pressure be maintained?

Are harmful or flammable airborne contaminants present?

Are oxygen levels safe?

Is there a risk of engulfment or submersion?

What PPE or safety equipment can be used to improve worker safety? (I.e. access safety equipment – like fall arrest systems for working at height – can provide safeguards for entering and exiting confined spaces, and vital support during rescue efforts too.)

 
Competency and training
 
According to Fire and Safety Australia, 92% of Western Australia’s confined space fatalities in the last 15 years were due to inadequate training, and over 90% of these fatalities cited a lack of supervisor knowledge and supervision as the secondary cause – making training a critical factor in keeping people safe.
 
To work in these environments a unit of competency for entering and working in confined spaces is required. Additional training modules are available for performing rescues and supervising work in confined spaces. Much like competency for working at height, retraining is not required by law, but it is recommended at 1-2 yearly intervals to ensure safe practices and to stay abreast of any changes in legislation.
 
“Most importantly, if you’re unsure about the nature or safety of your workspace, always stop work and seek further guidance – never proceed until you feel safe,” says Michael.
 
Is confined space safety a concern for your business? How do you overcome the challenges to keep people safe? Please share your thoughts and feedback via LinkedIn.