Blast cleaning using shot and grit

You may use shot and grit in your mechanical cleaning processes.

Shot or grit blasting removes contaminants, such as rust, paint, scale, swarf, oil and grease, before processing or coating your metal product. You may also use it to increase the surface area of your metals.

Your systems may have a closed circuit for the abrasive material used in blasting. This reuses the shot or grit and reduces the amount of abrasive material you use. You can wet-propel, in a water suspension, or dry-propel the abrasive material.

What you must do

Comply with your permit

If you have a permit, licence or registered exemption you must comply with its conditions. Your permit may contain conditions relating to your levels of noise or air emissions. You can be fined or even sent to prison if you do not comply with conditions.

Prevent nuisance

Mechanical cleaning can have significant impacts on your local air quality and can cause noise pollution. You may have to take steps to control air quality and prevent noise pollution from your site.

If your process creates levels of noise or odour that could cause a nuisance or harm the health of the surrounding community, your local council can issue an abatement notice that:

• requires you to reduce the nuisance
• bans or restricts the nuisance
• requires you to carry out work or take other steps to reduce or stop the nuisance.

Anyone who is affected by the nuisance, such as your neighbours, can apply to the court in Northern Ireland or sheriff in Scotland to issue you with an abatement notice.

You can be fined if you do not comply with an abatement notice, and the local council can take steps to stop the nuisance itself and charge you for its costs.

Noise, odour and other nuisances

Comply with your waste responsibilities

You must comply with your duty of care responsibilities when you manage your waste.

If your spent shot or grit is contaminated, you may need to deal with spent shot and grit as hazardous/special waste. For more information, see our guidance on hazardous/special waste.

Check if you need any discharge consents

Do not discharge to public sewers, surface waters or ground waters without consulting your regulator. You may need a discharge consent or other authorisation. For further information, see our guidance on discharges to water and sewer.

Good practice

Reduce your air emissions

• Cover your spent grit or shot while you are arranging its disposal. This will reduce your dust emissions.
• Check the condition of seals and pipework on your grit blasting equipment regularly. Replace any damaged pipework to reduce your dust emissions.
• Add a small amount of water to your spent grit-blasting materials to form a solid mass. This will reduce the likelihood of you causing a dust nuisance.
• Install an air extraction system in your grit blasting areas. Use a cyclone extraction system that allows your material to be sorted by size. This will also enable you to reuse correctly sized grit in your system.

Prevent noise nuisance

• Keep all doors to your grit blasting areas closed to contain noise within your building.
• Use sound reduction measures, such as insulated screens, to reduce your noise levels.

Be an efficient operator

• Wipe your material surfaces with rags prior to grit blasting to minimise contamination of your metals. Ensure that the rags you use are recovered or disposed of at an appropriately authorised site.
• Regularly check the condition of your grit-blasting material to avoid disposing of it unnecessarily.

Control hazards at your site

• Vacuum up, rather than sweep up, any materials you spill to avoid combustion of the metal dusts.
• Ensure you have good airflow through your production and working environment. Monitor this regularly using airflow measurement equipment.