What should empty gas cylinders be marked with?

Empty gas cylinders should be marked with "MT" or "Empty" to clearly indicate that they no longer contain gas. This marking is essential for safety and proper handling in various environments, particularly in industrial and welding settings. By labeling empty cylinders appropriately, workers and safety personnel can prevent accidents associated with mistakenly using or mishandling cylinders that might still be hazardous, even if they are empty. This practice is part of ensuring a safe working environment, as it guides users in identifying cylinders that are safe to handle and those that are not.

Marking empty cylinders helps maintain an efficient inventory system and aids in regulatory compliance, as proper labeling is often required by safety regulations governing the storage and transport of gas cylinders.