Designing out risk and hazards when using Class 3 Flammable Liquids 

Oct 2, 2019 Posted by Walter Ingles

This blog is part of an informative series on the 10 Principles of Good Work Design — as they relate to Class 3 Flammable Liquids. Today we’ll be explaining how to break down a job task to design out risks and hazards. Any job task involving flammable liquids needs careful evaluation because misunderstandings or errors by workers can easily result in a fire, explosion, or serious chemical burn. 

“Principle 4 — Good work design addresses physical, biomechanical, cognitive and psychosocial characteristics of work, together with the needs and capabilities of the people involved.” Safe Work Australia.  

Breaking down a job task 

Good Work Design Principle # 4 focuses on breaking down a job task to identify (and hopefully) design out the risk and hazards. There are four work characteristics to consider when work is designed, redesigned or a risk assessment is conducted. We outline each below and use the following workplace example to demonstrate what we mean. 

WORKPLACE EXAMPLE: a petrol-powered compressor is refilled once a day with a jerry can and attached plastic funnel. The funnel doesn’t create a complete seal around the nozzle, and sometimes petrol spills down the side of the container. The compressor is located on a mezzanine floor and workers have to climb a grilled stairwell to access the machine.  

1. Physical characteristics

When working with flammable liquids, your people can easily be exposed to multiple hazards just by carrying out a single task. You’ll need to identify all the physical and chemical hazards associated with the task. Based on our example you might identify:

  • Physical hazards - the worker needs to carry the jerry can up a flight of stairs (working at height), then reach up to the compressor to pour the petrol. The compressor is often hot from running. It is very noisy and hearing protection is required. There is a pedestrian walkway below the mezzanine floor.  
  • Chemical hazards - if spilled, petrol is a skin and eye irritant. Petrol that is ingested or swallowed is toxic, corrosive and carcinogenic. Inhaling petrol fumes can cause immediate drowsiness and impairment, larger doses can be fatal. 
  • Physiochemical hazards - the petrol is highly flammable and can explode at certain temperatures.  

 2. Biomechanical characteristics

Next, consider the biomechanical characteristics of the work task — ie, how the human body responds to forces and other external stimuli. From our earlier example you might determine: 

  • Force - workers need to take care not to over-pour. 
  • Movement - climbing stairs carrying jerry can, holding the loose funnel in place to stop spillage. 
  • Posture - the compressor is raised so workers stretch up to pour the fuel. Their body is not stable or grounded on two feet. 
  • Vibration - the mezzanine floor vibrates when the compressor is running, sometimes workers leave it running so workflow is not interrupted. 
  • Repetition - the worker refills the compressor once a day, imagine if they needed to refill the compressor every hour. 

3. Cognitive characteristics

Cognitive characteristics refer to the thought power and concentration required to carry out the task. It is important to note, this characteristic is about the complexity of the task, rather than the cognitive ability of the worker. 

  • Information processing load - the filling of the compressor with petrol may seem a simple task to cognitively process, but what if the worker is asked to perform another 3 tasks in rapid sequence? 
  • Duration - this task is simple, and the worker should only require focused concentration for a few minutes.  
  • Complexity - it’s a relatively simple task, but could become more complex when the funnel is leaking or the compressor is hot. 

4. Psychosocial characteristics

Finally look at the psychosocial characteristics at play in the workplace — peers, culture, supervision, job control. 

  • Work demands - is there a heavy production schedule? Is the worker in a rush to get the compressor filled before shift change? 
  • Peer support - does the task require a buddy system? And if this was in place, would co-workers support the worker filling the compressor? Are there any cultural disputes or workforce divisions? 
  • Supervision - do supervisors carry out periodic checks to ensure the compressor is being filled correctly, and workers are wearing PPE? 
  • Job Rotation - is the task always performed by one worker, or assigned arbitrarily? Are new or untrained workers ever permitted to fill the compressor? 
  • Timing - is the task carried out just before shift change or in the middle of production? 


Considering Individual workers 

Once you have broken down the job task and evaluated each of the characteristics, you must also consider the actual people who carry out the task. Good work design streamlines job tasks to accommodate the abilities and limitations of your workers (where practicable).  

  • Training - what inductions and on-the-job training has the worker received? Do they fully understand the chemical hazards in play? 
  • Experience - how many times has the worker carried out the task previously? Are they a new worker? 
  • Physical health - is the worker overweight? A smoker? Have allergies? Had long-term exposure to hazardous chemicals? Have an injury or disability?  
  • Cultural - is the worker a native English speaker?  
  • Body size - is their body large which restricts movement in small areas, or are they tiny and at higher risk of injury when lifting? Does their PPE fit them correctly? 
  • Attitude - does the worker have a history of ignoring instructions? Or wandering off? Or losing their PPE? 
  • Shifts - is the worker on a FIFO roster? Are they getting enough rest and recovery time between shifts?  

IMPORTANT: If workers are assigned arbitrarily you may also need to consider the supervisor and their methods of selection, supervision and training. 


Evaluating other work processes 

Good work design means considering each of the above factors in combination, and never basing an operational procedure on one characteristic in isolation. At the same time, you will also need to consider what other work processes are occurring at the same time (production, shift change, late at night). 


Next steps 

Using Class 3 Flammable Liquids and other Dangerous Goods at the job site brings a huge WHS responsibility for business owners and operators. For more information about meeting your flammable liquids compliance obligations, please download our free eBook Essential Considerations When Storing Flammable Liquids Indoors. Download and read it today by clicking on the image below:  

Essential Considerations when Storing Flammable Liquids Indoors download Free eBook

Walter Ingles

Walter Ingles Compliance Specialist

Walter is STOREMASTA’s Dangerous Goods Storage Specialist. He helps organisations reduce risk and improve efficiencies in the storage and management of dangerous goods and hazardous chemicals.

Like what you’re reading?

Subscribe to stay up to date with the latest from STOREMASTA®

Recommended Resources

Dangerous Goods Segregation Guide

How to segregate incompatible classes of dangerous goods

Segregate the 9 different classes of dangerous goods in a way which will reduce risk to people, property, and the environment.

Learn more

Reviewing the substitution controls in your Class 3 Flammable liquids storage and handling areas 
From the blog

Reviewing the substitution controls in your Class 3 Flammable liquids storage and handling areas 

If you’ve implemented any type of substitution control in your Class 3 Flammable Liquids storage and handling areas we ...

Learn more

What Is Meant by Safety and Health in the Workplace? 
From the blog

What Is Meant by Safety and Health in the Workplace? 

This week we’ve published a Guest Post by Alert Force — The Health and Safety Training People. Alert Force is a ...

Learn more

Engineering and isolation controls to support your flammable liquids store 
From the blog

Engineering and isolation controls to support your flammable liquids store 

One of our primary aims here at STOREMASTA is helping our clients and customers better understand the chemical hazards ...

Learn more

Choosing spill bunding for your flammable and combustible liquids 
From the blog

Choosing spill bunding for your flammable and combustible liquids 

What’s the first thing that comes to your mind when you think of a chemical spill? A major oil spill affecting the ...

Learn more