‘It’s easy to be wise after the event’ says Sherlock Holmes, but when workplace safety is involved it’s essential to analyse dangerous incidents and workplace accidents — using the information to improve the safety of the work environment. In this blog we’ll be unpacking some of the requirements of AS4332-2004 - The storage and handling of gases in cylinders by discussing three workplace accidents that could have been avoided if the guidelines in the Standard had been implemented.
PLEASE NOTE: The accidents identified in this blog occurred in the USA, so this blog is not about establishing blame or pointing the finger. It’s about demonstrating that introducing the measures set out in the Standard can help you avoid dangerous incidents involving compressed gases in cylinders, and create a safer workplace or job site.
1. Using gas cylinders at height
Two workers needed to use compressed nitrogen gas to leak-test some HVAC units installed in the roof of a warehouse. To reach the HVAC units, the workers used a rolling staircase with a landing platform then continued up a fixed ladder. One worker tried to climb the fixed ladder while holding a 15.8kg nitrogen cylinder in one hand. He lost his balance and fell, hitting first the landing area then continued falling more than 5 metres to the concrete floor below. He broke his back.
Even though this accident caused a lifelong injury to one of the workers, the incident could have been a whole lot worse. The cylinder could have struck another worker, or the impact from the fall could have ruptured the cylinder turning it into a torpedo like projectile.
Section 5 of AS4332-2004 (which deals with operational and personnel safety) requires that a suitable trolley or lifting device must be used when moving cylinders about the workplace. Additionally cylinders must be kept securely restrained while being moved so their valves and any fitted regulators cannot be damaged.
In this instance a safe work area could have been created by transporting the heavy nitrogen cylinder in a gas cylinder cage or lifting cradle. The gas cylinder cage could then be kept in place for the duration of the scheduled maintenance on the HVAC units. Compliant gas bottle cages have inbuilt dividing bars and cylinder restraints to prevent the cylinders moving while being lifted and transported.
2. Transferring cylinders onsite
A worker was moving an empty nitrogen cylinder down a passageway. He was actually pushing the cylinder along the ground while pulling an empty cylinder trolley along behind him. Somehow the wheels of the gas cylinder trolley became jammed in a crack on the floor and the whole trolley tipped over. Somehow the worker’s index finger became trapped between the cylinder and the gas bottle trolley. His finger was amputated.
As we outlined in item 1 (using gas cylinders at height), the Standard requires that gas bottles must be secured during transfer or movement about the worksite. Mechanical lifting devices and trolleys must be used at all times. Had the worker used the cylinder trolley properly, he would very likely still have all 5 of his fingers.
Of course we have no way of knowing why this worker (who had the correct safety equipment in his possession) chose not to use it. It could be an indication that:
- The worker didn’t understand the full extent of the dangers and hazards when transporting the cylinders
- The worker didn’t know that empty cylinders must be handled and stored in exactly the same way as full cylinders
- The worker had not received suitable task-specific training and didn’t know how to use the cylinder trolley properly
- There was inadequate supervision at the worksite
- Risk assessments conducted on the manual handling tasks at the worksite were inadequate and had led to the purchase of handling equipment not suited to the gas cylinders actually being used
The Standard requires that staff and contractors are given thorough training so they understand the full risks to their safety when handling the cylinders; know their responsibilities under the law; and know how to use safety equipment and PPE. At the same time observation on the job and regular follow up training is required.
3. Correctly identifying gas cylinders
A worker at a metal recycling plant was using a large backhoe to shear and crush metal. In the pile of rubble he came across a gas cylinder and (only looking at the colour of the cylinder) wrongly assumed it was an oxygen cylinder. The empty cylinder still contained acetylene and when the shearing jaws of the backhoe crushed the cylinder it exploded, creating a large fireball. The worker suffered severe burns and was hospitalised.
The Standard clearly states that the colour of a cylinder should never be used as the sole means of identifying the contents. Additionally the original owner of the acetylene cylinder had a duty of care to safely dispose of old and damaged cylinders safely and correctly. Even ‘empty’ cylinders still contain residue of the gases previously stored, and must be treated with the same care and responsibility as full cylinders.
Of course an acetylene cylinder should never have been sent to a scrap metal facility in the first place, but sorters and backhoe operators at these workplaces require adequate training about how to proceed if encountering gas cylinders.
For more information about how to safely handle and store gas cylinders at your workplace (and meet the requirements of AS4332-2004 - The storage and handling of gases in cylinders) download our free eBook Gas Cylinder Storage: Compliance and safety requirements. We use genuine workplace examples and case studies to demonstrate how the Standard works in the real world. Download it today by clicking on the image below: