Applying metallic coatings

This guidance is relevant if your business uses thermal spraying processes for metallic coatings. Thermal spraying uses gases or compressed air to propel heated metal powder towards the component to be coated.

After you have applied the metal powder, you can seal the surface of your component with another coating. Your second coating is usually solvent based.

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 controlling your noise, odour or air emissions. You can be fined or even sent to prison if you do not comply with conditions.

You must also comply with controls on solvent emissions. For further information, see our guidance on solvent emissions.

Prevent nuisance

Your metallic coating activities could cause significant levels of noise from thermal spraying and odour from using solvents. You may have to control noise and odour from your premises.

If your process creates levels of noise, dust, grit, fumes or smoke 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.

You may need to deal with some of your waste as hazardous/special waste, including:

• organic solvent paint, containers and thinners
• some metal powders, eg aluminium
• 'wet-back' extraction booth water
• air extraction unit filters
• scrubber blow down liquids.

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 emissions

• Store your powders, especially aluminium powder, in a dry storage area to prevent powders emitting toxic arsine gas if they become damp.
• Control your dust emissions by ensuring that your equipment amperage and gas supply are set up to achieve efficient deposition.
• Use extraction ducts to prevent dust from accumulating in your pipes.
• Store extracted dust in covered containers.
• Maintain your abatement equipment regularly to make sure it works efficiently.

Control hazards at your site

• Vacuum clean your spraying booths regularly, using a spark-free system to reduce the risk of explosions.
• Read the information on the safety data sheets of all metal powders before you apply them because many powders are flammable.
• Take care when you spray aluminium because some forms are explosive and flammable.
• Ensure you have good airflow through your production and working environment. Monitor this regularly using airflow measurement equipment.

Use your resources efficiently

• If you have large amounts of metal overspray you may be able to recycle it.
• Inspect your items before you coat them to avoid wasting coating material on obvious rejects.
• Reduce your solvent consumption by wiping excess coating material from your spray guns before you clean them.
• Mop up rather than washing down your spills. This will reduce your water use and the risk of water pollution.
• Ensure that you fully drain paint cans before you send them for recovery or disposal.
• Mask off empty positions on your jigs to reduce the amount of cleaning required.

Be a good neighbour

• Speak to your neighbours regularly about any issues with noise, odour or other nuisances at your site.
• If you receive any complaints about noise, odour or other nuisances deal with them quickly.
• Record the results of investigations into complaints and anything you do to correct the problem.