Stoneworkers - Frequently asked questions
How can I reduce vibration on a stone hammer?
Vibration is worst on the traditional in-line stone hammers without anti-vibration features - typically around 20m/s2 on the tool body and may be even worse on the chisel. It is usually lower on D-type handles and lowest on pistol grip hammers. This level of vibration exposes stonemasons to high risks of hand-arm vibration syndrome (HAVS) after a very short period of use.
Air pressure supplied to stone hammers has an effect on the vibration generated. Lower air pressure generally results in lower vibration on the tool body, but the tools may also be lower powered. Always refer to manufacturers' instructions for the correct operating pressure. Make sure that you do not use the tool at a higher operating pressure than is necessary for the job.
Not all the stone hammers generate the same risks from vibration as the traditional ones. Vibration reduced stone hammers are available and may be suitable. The vibration from these tools are generally lower than the traditional in-line stone hammers. Consider replacing the high vibration traditional hammer with the vibration reduced ones. However, additional training maybe required on techniques of using these tools due to different designs.
Vibration reduced chisel sleeves are also available. Vibration generated on these types of chisel depends very much on the hammer the sleeve is used with. Used with smaller and lower powered hammers like the pistol grip ones can result in not only the lower levels on chisel sleeves, but also on the tool body itself.
Do Limestone and Marble contain Silica?
Yes, both Limestone and Marble contain silica. The level of crystalline silica in limestone is usually, but not always, below 2%, whilst that in marble is typically below 5% although it can be as high as 30%. When any stone containing crystalline silica is cut, polished or worked in any way the dust produced contains respirable crystalline silica (RCS). As RCS is hazardous when breathed in, you need to control exposure to the dust generated by working limestone or marble.
Does artificial/engineered marble pose a risk to health?
Yes, when cut or worked in any way that creates dust. Engineered marble, also known as artificial marble, is a popular alternative to natural marble, especially for worktops. The composition of artificial marble will vary compared to natural marble, with artificial marble usually containing crushed marble bound in a resin. The RCS content of artificial marble may be as high as 30%.
How can I protect my health when cutting stone?
Worker exposure to RCS must be controlled by the use of good control practices, as given in Schedule 2A of COSHH (need link to website). Control measures should reduce exposure to airborne RCS to below the workplace exposure limit (WEL) of 0.1mg/m3 and be proportionate to the health risk. In most cases simply achieving the WEL would not be deemed 'adequate' control. You will find information on how to control exposure to stone dust at the following links:
Is there any risk from using compressed air to remove stone dust?
The use of compressed air to remove dust presents a number of risks to both the health and safety of those involved.
There is a risk of compressed air entering the operator's bloodstream, which can result in death.
Eye injury including blindness can occur if dust particles bounce back at the operator.
The use of compressed air may also increase dust levels in the area.
Noise levels are normally high and there is a significant risk of permanent hearing damage from prolonged exposure. Hearing loss can never be restored.
Can I sign a disclaimer not to wear PPE?
No. Employers must provide personal protective equipment (PPE) when health and safety risks cannot be adequately controlled in other ways. Since PPE is a 'last resort', it is important that you wear it all the time you are exposed to the risk. No exemptions should be allowed for those jobs which take 'just a few minutes'. The PPE needs to be:
- maintained and stored properly;
- provided with instructions on how to use it safely; and
- used correctly by employees.
Employees should receive information, instruction and training on why PPE is needed, when to use it, how to use it, as well as instructions for repair/ replacement and the limitations of it. Employers need to make sure employees are using it properly.
I have an overhead crane in the workshop. What is meant by the term 'lift plan' and do I have to do one before I carry out every lift?
A 'lift plan' allows you to identify the ways in which you can eliminate or control the risks involved in a lifting operation. The degree of planning for a lifting operation should be proportional to the risk and will vary considerably depending upon the complexity of the lifting operation. The complexity will depend on the load to be lifted, the equipment to be used and the environment in which the operation is to be undertaken.
Proper planning of lifting operations is a combination of two parts:
- initial planning to ensure that lifting equipment is provided which is suitable for the range of tasks that it will have to carry out; and
- planning of individual lifting operations so that they can be carried out safely with the lifting equipment provided.
The balance between the two parts of the planning process will also vary depending upon the lifting equipment and the particular lifting operation.
For routine (basic) lifting operations an initial plan may only be required once but you may need to review it occasionally to make sure that nothing has changed and the 'plan' remains valid.
For complex lifting operations you may need to plan the task each time it is carried out.Find out more - HSE webpages on planning and organising lifting operations