The Management of Health and Safety at Work Regulations place a legal requirement to undertake a risk assessment prior to undertaking a work activity.
Risk management is a step-by-step process for controlling health and safety risks caused by hazards in the workplace. The key steps in the risk assessment process are:
- Identify hazards
- Assess the risks
- Control the risks
- Record your findings
- Review the controls
This all seems fairly straightforward, especially the first step, identifying hazards. However, there is a glaring issue.
If you were asked to identify electrical hazards within a facility and you weren’t a trained and qualified electrician, would you be able to correctly identify all the electrical hazards?
Remember, if you can’t identify the hazards then you can’t assess the risks.
This is especially true with respect to compressed gases. We are frequently asked to review organisations’ gas-specific risk assessments and method statements and tend to find rather glaring errors, as the person who has undertaken the risk assessment has received little or no training in the identification of gas hazards.
Use a Team to Undertake Your Risk Assessment
We always encourage organisations to use a team of people to undertake the risk assessment for one very good reason, if an operator or manager is asked to undertake a risk assessment in their particular work area, they’ll always see what they’ve always seen.
One or two new sets of eyes from different departments will always provide fresh impetus into the risk assessment process.
The Main Hazards Associated with Compressed Gases
So, what are the main hazards to take into account with respect to compressed gases? They can basically be put into five categories:
- The gas cylinders themselves
- The gases compressed inside the cylinders
- The release of gases at very high pressures
- External influences
- Other related considerations
Gas Cylinders
Gas cylinders are five feet tall, they weigh nearly 90 kg and they stand on a ten-inch diameter base. They are basically a very big, heavy pencil stood on its end. They are inherently unstable.
The key points to consider with gas cylinders are upright, secure or under direct control.
Gas Properties
Depending on the properties of the gases, a release may create a hazardous atmosphere, for example an asphyxiant, flammable, oxidant, toxic or corrosive atmosphere.
Pressure Release
Gas cylinders contain gases stored under pressure and may have significant stored energy. Any pressure above atmospheric pressure that is released from a cylinder has the potential to cause injury to personnel, or damage to plant or property. The higher the pressure, the greater the hazard.
A release of pressure can occur from a variety of activities such as incorrect set-up of equipment, the use of old or poorly maintained equipment, or the venting of pressure relief devices.
External Influences
The major external influence which will affect a gas cylinder is the air temperature that the cylinder is exposed to.
If gas cylinders containing gas molecules are subjected to high temperatures the internal gas pressure will increase, increasing the risk of gas leakage. For cylinders containing liquefied gases, such as carbon dioxide or propane, high external temperatures may activate pressure safety devices, resulting in a release of gas into the working environment. Such high temperatures may result from a fire, extreme weather conditions, local sources of heat, direct flame impingement or steam.
Low temperatures may cause embrittlement of the gas cylinder itself, which may increase the likelihood of a rupture. Cold temperatures may also create handling difficulties — it is certainly hazardous to move a large gas cylinder over ice — and may cause the separation of some gas mixtures.
Other Related Considerations
These could include such things as operator working practices, the use of incorrect flow rates or excessively high working pressures, the production of excessive welding fume within the workplace, or having too many gas cylinders on site causing manual handling difficulties in storage areas.
Control Measures for Compressed Gas Hazards
Having considered the hazards that may be present, appropriate controls need to be implemented to reduce any risk to an acceptable level.
If your staff require training in how to identify compressed gas hazards and implement effective control measures in order to work safely, please contact us on 01270 758890 or at admin@gassafeconsultants.co.uk.
