In order for a cylinder to be filled with air it must have a valid test stamp or sticker.  If this is not present, or it is out of date, then the cylinder will not be filled and must undergo testing. Cylinder.

Test Process - Visual: 

• The cylinder will be inspected externally - the boot will be removed along with any stickers or labels so that any rusting or damage can be inspected. If there is significant surface corrosion, then the cylinder will need to be cleaned, zinc plated and repainted. 
• The valve will then be removed, cleaned and serviced.  Any worn parts will be replaced. If the valve is obsolete (no service kits available) or damaged it will not be reinstalled and you will have the option to replace the valve. 
• The cylinder neck thread will be checked with a measuring gauge to ensure it is undamaged and tight. If the cylinder neck thread test fails, then the cylinder will not be returned and will be scrapped due to the risk of catastrophic failure. 
• The cylinder will be inspected internally for defects, rust spots etc. If there is slight corrosion, then the internal surface may be cleaned by shot blasting. Major internal corrosion will result in the cylinder being scrapped due to the risk of catastrophic failure. 
• Reassembly and filling. 

NOTE: Please be aware that cylinders with severe internal corrosion that cannot be removed by shot blasting will not be returned and will be destroyed - this is an HSE requirement because they are no longer safe to be filled due to the risk of catastrophic failure.