Gas or liquid receptacles made of a single piece of capacity between 5 and 150 liters are commonly referred to as cylinders. Pursuant to art. 241 Presidential Decree 547/55:

“systems, plant parts, appliances, receptacles and piping subject to pressure of liquids, gases or vapors, which are in any case excluded or exempted from the application of the safety standards required by the laws and special regulations concerning pressure plants and containers, must possess the necessary requirements of resistance and suitability for their intended use”.

In particular, the cylinders must be tested and periodically reviewed. Testing and revision are the responsibility of the owner (Ditta Fornitrice). This means that the empty cylinders must be returned to the supplier company, also the supplier company must be contacted if the validity of the test has expired, the expiry date is reported by punching on the tank body. Failure to return the vacuums or the use of expired cylinders, makes the purchaser responsible for the consequences that may derive from the use of the same. Everyone must therefore take care of the recipients purchased until their return.


A gas container must be put into use only if its contents are clearly identifiable. The content must be identified in the following ways.
a) coloring of the ogive, according to the color codified by the law ( Color codes of the ogives of the gas containers) ;
b) trade name of the gas, indelible inscriptions, self-adhesive labels, decals placed on the container body, or identification tags attached to the valve or to the protection cap (labeling);
c) valve outlet fitting, according to the law,
d) types and characteristics of the containers.
It is therefore important that the user does not cancel or make illegible writings, do not remove labels, decals, tags applied on the containers from the supplier for the identification of the contained gas. Containers containing gas must be stored in suitable places: they must not be exposed to direct sunlight, nor kept close to sources of heat or in environments where the temperature can reach or exceed 50 ° C. they must not be exposed to excessive humidity or corrosive chemicals.

It is forbidden to store containers containing gas with their gases in the same place. It is also necessary to avoid storing the containers in places where combustible materials or flammable substances are found. In the storage areas, full containers must be kept separate from empty ones, using suitable wall signs to distinguish the respective deposits of belonging. During use or in places of storage, the containers must be kept in a vertical position and secured to the walls or to any solid support with chains or other suitable means, to avoid overturning, except that the shape of the container ensures its stability. prohibited to use horizontal or upside-down cylinders.

Once the container is secured, the valve protection cap can be removed. The valves of the containers must always be kept closed, except when the container is in use. The opening of the container valve must take place gradually and slowly. Never use keys or other tools to open or close valves with a handwheel. For hard valves to open or seized due to corrosion, or if the valve or fitting appears damaged, contact the supplier for instructions and avoid using the gas. Before returning an empty container, make sure that the valve is tightly closed, screw the blind cap onto the valve spout and replace the protective cap. Always leave a slight positive pressure inside the container.

The user must not change, tamper with, plug the safety devices that may be present, or in case of gas leaks, repair the full containers and the valves. Valve lubrication is not necessary. It is absolutely forbidden to use oil, grease or other combustible lubricants on the valves of the containers containing oxygen and other oxidizing gases. Before returning an empty container, the user must make sure that the valve is tightly closed, then screw the blind cap on the valve spout and then replace the protective cap. It is advisable to always leave a slight positive pressure inside the container.

The containers must be handled with care, avoiding violent shocks between them or against other surfaces, falls or other mechanical stresses that could compromise their integrity and resistance. The containers must not be lifted by the cap, dragged or rolled or slipped on the floor. Their movement, even for short distances, must take place by hand trolley or other appropriate means of transport. Magnetic elevators or slings with ropes or chains must not be used to lift the containers. Any lifting by crane, hoists or lift trucks must be carried out using only the appropriate cages, or metal baskets, or special pallets.

Vessels should never be placed where they could become part of an electrical circuit. When a container is used in connection with an electric welding machine, it must not be grounded. This precaution prevents the vessel from being ignited by the electric arc.