This document provides advice and guidance for safe gas cylinder storage. It gives guidance on the construction and management of gas cylinder stores and provides information on the hazards likely to be encountered.
It shall be used when sitting and constructing storage facilities or when reviewing the safety and suitability of existing storage facilities. It does not preclude the use of alternative designs, materials, and methods when they provide equivalent standards of safety.
The content of this publication is in line with advice from the Health and Safety Executive (HSE).
If you need any help on a project that involves gas cylinder storage then you need to check out our Gasvault range here.
This document defines the principles of safe practice for the storage of gas cylinders and gas cylinder bundles and outlines the relevant legal requirements.
Cylinders are never fully empty unless a cylinder is new, de-valved, or following inspection and test where it has not yet been filled with a gas. Therefore, cylinders, containing a gas but regardless of the quantity of gas, shall all be treated in-line with this Code of Practice.
A gas cylinder(s) is deemed to be in storage when:
Storage of full and empty LPG cylinders and cartridges. Where a mixture of LPG (>400 kg) and other gas cylinders are stored then the applicable sections of UKLPG CP 7 (60) and this Code should be applied.
Exclusions from this Code of Practice are:
(i) Cylinders in use i.e. connected to the user equipment, or permanently connected for use; for example, fire protection systems and specifically sited emergency response equipment, such as fire extinguishers and self-contained breathing apparatus.
(ii) Cylinders being processed for filling or for periodic inspection and test.
(iii) Medical cylinders in domiciliary use.
(iv) Gas cylinders during carriage by road, rail, air, and sea.
(v) Cylinders permanently manifolded together to form part of a bulk gaseous hydrogen installation.
(vi) Transportable vacuum insulated containers.
(vii) Containers (vessels) for cryogenic liquids.
(viii) Cylinders stored off-shore.
The cylinder label shall always be used as the primary means of identifying the contents of gas cylinders. The label will identify the product name and the class of hazard (Diamond Hazard Label(s)). Some gas cylinders may have this information stenciled on the body of the cylinder.
Colour coding is a secondary method of identifying certain gases or the properties of others, however, colour coding is not mandatory for most gases but its use is supported by the majority of gas suppliers. Colour coding is typically applied to the shoulder, or curved part, at the top of the cylinder.
Gas cylinders present a number of different hazards:
Gas cylinders are generally heavy and are relatively unstable due to the base diameter to height ratio. Large cylinders can weigh over 100 kg when full they are easily toppled over. Gas cylinders are awkward objects to move safely.
Cylinders contain gases stored under pressure and will have significant stored energy.
Any pressure above atmospheric released from a cylinder has the potential to cause injury to personnel or damage to plant or property.
Pressure can be released by:
All gas cylinders contain gases under pressure and may present a risk of explosion if not safely handled and stored. Legislation requires that a site-specific risk assessment is required for each gas cylinder store, refer to The Management of Health and Safety at Work Regulations (6) and The Dangerous Substances and Explosive Atmospheres Regulations (DSEAR). Every storage situation must be considered on its merits and special circumstances may necessitate variations on the recommended requirements.
Consent from the local authority may need to be obtained to store quantities of dangerous substances over certain thresholds. The regulations contain thresholds for both named substances, such as oxygen and hydrogen, and for generic categories of substances (flammable, toxic). For example, the threshold for oxygen storage is 200 tonnes, for flammables 50 tonnes, but for hydrogen only 2 tonnes. In some cases, the percentage / partial faction of thresholds (for example, flammables and oxidants) are additive when determining if consent is required.
The majority of gas cylinders are designed so that they can be stored in the open air and, as such, they will not be adversely affected by inclement weather.
Storage areas should be located in an external area where there is good natural ventilation. Adjacent buildings, structures, and geographical features may adversely affect natural ventilation and their effect should be taken into account during the risk assessment. The store should not be located in low lying areas; where gases may accumulate.
Storage within a building is not recommended. Where storage indoors cannot be avoided please see below. Internal storage locations should be at ground level and in the following order of preference:
(i) A bespoke stand-alone dedicated, adequately naturally ventilated building.
(ii) A dedicated room sealed from the rest of the building, adequately naturally ventilated to the outside, only accessible from an external door(s).
(iii) A dedicated room, adjacent to an outside wall, inside a building, adequately naturally ventilated to the outside, sealed from other areas of normal occupancy.
(iv) A dedicated room, inside a building, with forced air ventilation, sealed from other areas of normal occupancy.
(v) In a building, as far as is practicable away from normal work locations.
The location of the store shall take account of the minimum recommended separation distances, refer to Section 5.4.1. Cylinder stores are to be located away from the site designated emergency exits and escape routes.
Gas cylinder storage areas should be segregated from other stores. The risk assessment shall take due regard of the potential hazards of the gases being stored and the risk from other hazardous processes or storage sites that may impact on a cylinder store. It shall also consider the potential for impact due to vehicle movements.
Storage locations should be sited at ground level. Where cylinders are stored at any other level this shall be specifically covered in the risk assessment. If the store is located at another level then consideration needs to be given to providing an area to allow vehicles to collect and deliver cylinders, cylinder movements between levels and the impact in the event of an incident, for example, gas leakage, fire, access for emergency services, proximity to people, etc.
The risk assessment shall take account of both underground and overground services. The location shall be chosen so that it is not directly beneath overhead power or other cables and where it will allow access for vehicles and other plant machinery without the risk of them coming into contact with power or other cables.
Each storage area and its boundaries shall be well defined. The footprint of the store shall allow space for the expected quantity of gas cylinders being stored as well as for the safe movement and handling of the gas cylinders, including access for mechanical handling equipment.
Appropriate access to the site will be required. This will include access for delivery vehicles and the emergency services.
The location of the storage area should consider the security of cylinders to avoid theft and to prevent tampering with the cylinders.
The physical dimensions of the storage area shall take into account the storage requirements, for example, grouping by hazard classification, full/empty or unserviceable cylinders and providing adequate space for access and egress, for safe manual handling operations and the use of mechanical handling equipment.
Means shall be provided to secure cylinders to prevent them from falling over, for example, pallets, chains, lashing, etc.
Appendix 2 shows the minimum recommended separation distances between cylinders, the store(s) and other features.
Where there are space restraints a permanent physical partition may be used to help achieve the required minimum recommended separation distances. The height of the partition should be relevant to the hazard, however, it should be not less than 2 meters high, unless for non-fire hazards a lower partition can be justified through risk assessment. The required minimum recommended separation distance can include the length of the sides of the partition, as shown in Figure 1. Such partitions should be imperforate and constructed of suitable materials, for example, solid masonry or concrete. Where protecting against fire hazards, they should be constructed to achieve at least 30 minutes’ fire-resistance for best practices in gas cylinder storage.
Where the wall separates vulnerable populations from the cylinders (not including inert gases), the fire resistance provided should be a minimum of 60 minutes.
Figure 1: Use of a partition to achieve the minimum recommended separation distances
Within Figure 1 the minimum recommended separation distances may include the distance measured around the sides of the partition by determining the sum of A + B + C.
If flammable gas cylinders are stored against a building wall the area up to 2 m either side of the storage area and up to 9 m above ground should be imperforate and of a minimum of 30 minutes fire resisting construction.
When planning the gas cylinder storage facility, adequate handling space shall be allowed. The total amount of floor space required will depend on the quantity and the size of the cylinders, and the handling equipment to be used during their movement. Refer to Section 6 and Section 8.
The floor should be level and constructed from non-combustible, non-porous material. All floor surfaces shall be constructed so that they can be maintained in a clean manner.
Obstacles such as expansion joints, steps, and drainage systems, shall not impede cylinder handling operations.
The floor shall be of sufficient strength to support the weight of the gas cylinders/gas cylinder pallets, plus any mechanical handling aids employed on gas cylinder handling.
The floor should be laid to prevent the accumulation of water so that stored cylinders do not rest in standing water and risk being subjected to corrosion.
Cylinders are designed for outdoor storage, however, some applications require protected storage conditions for quality, hygiene and security reasons, for example, analytical and medical gases. Cylinders may also need additional protection from local environmental conditions.
Where required, the roofing shall be designed to prevent gas pockets from accumulating, for example, gaps between the wall and sloping roof, natural ventilation in the roof apex etc.
All stores containing gas cylinders shall be secure and access shall be restricted to authorized personnel. This may be achieved by securing the site with a boundary fence with lockable gates or by securing individual stores. Dependant on the site security requirements both conditions may be required.
Suitable security arrangements shall take into account the classification of the gases and the quantities being stored. The security arrangements shall include appropriate physical and management security controls to prevent unauthorized access, theft, tampering, arson, vandalism and to effectively monitor the usage of gases, as well as any specific local considerations. Keys for each store shall be kept in a secure location and only issued to authorized persons; a log should be kept.
Where electronic security systems, for example, alarms, are installed comply with the electrical requirements on site.
The security perimeter shall meet the ventilation requirements and be not less than 1.8 meters high.
Where the gas cylinder store is enclosed, a suitable emergency exit(s) may be required dependant on the size and/or layout of the store.
All persons handling gas cylinders shall have appropriate training, as required.
Where high consequence dangerous goods, such as toxic gases, are stored on site a security plan shall be drawn up and implemented in compliance with the Health & Safety department.
Ventilation is required to ensure that any small leakage of gas is adequately dispersed and will prevent a hazardous atmosphere being created. An outdoor store with open or ventilated sides and is considered to provide adequate ventilation and is the preferred option.
Where a store may have restricted ventilation, due to, for example, adjacent buildings or a wall acting as a store boundary, it is necessary to ensure that there is through and thorough ventilation in all areas inside the store.
A semi-enclosed store may be considered ‘outdoors’ if it consists of up to three adjacent solid sides, with a roof, provided at least 25 % of the perimeter is constructed to ensure that ventilation is not impaired, for example, meshed cladding.
Where the configuration of the store restricts air flow, the installation of high and low-level vents should be considered to ensure a regular change of air. The design of a roof shall meet the ventilation requirements. Minimum recommended separation distances should be considered when locating vents.
A store with less than 25 % of the perimeter open is to be considered an indoor store.
Examples of store design are displayed below.
If a store is located against a building wall, then the risk assessment shall take account of the likelihood of escaped gas entering the building, and the method of entry, for example, an overhanging roof, cellars, windows, air intakes, etc.
The storage area should be located so that it is readily accessible for cylinder movements with manual handling distances kept to a minimum and clear access maintained at all times for deliveries and the emergency services.
Access to the delivery and storage area(s) is to be kept clear, with no parking allowed, except for the loading and unloading of cylinders. No vehicles are to be allowed within the minimum recommended separation distance.
Aisles should be provided to allow safe access to cylinders, to facilitate good housekeeping, stock control and for the ease of handling. They should be a minimum of 1 metre wide.
The layout of the storage area should allow for the safe movement of gas cylinder handling trolleys, forklift trucks, and any other powered vehicles. The layout shall take account of the separation of personnel and vehicles with appropriate traffic routes defined.
Where the gas cylinder store is enclosed suitable access and egress shall be provided. The risk assessment (refer to Section 5.1) shall determine the maximum travel distance to enable escape and therefore identify the number of exits required.
Where installed, all designated emergency exits shall open in the direction of escape and shall be fitted with panic furniture of a type not requiring a key, card, or code to open. They are to provide an unobstructed means of escape and in operation shall not obstruct any other escape route. These exits shall be properly identified by signage and maintained in a serviceable condition at all times. Ensure that emergency exits are secure and cannot be opened from the external side of the store (whilst still allowing emergency escape from the inside of the store).
The area should have adequate lighting to assist in providing a safe work environment, to allow the identification of the cylinder contents, signage and where necessary to assist with security. Where artificial lighting is used it shall give suitable colour rendering to enable colour labelling to be easily recognised by persons with normal colour vision.
Where required, emergency lighting shall be to the requirements of BS 5266 (28).
Only electrical equipment that is necessary for the safe and practical operation of the gas cylinder store shall be installed. As a minimum, all electrical installations shall conform to BS 7671 (31), Requirements for electrical installations. IET wiring regulations. Where flammable or oxidising gases are stored the risk assessment (refer to Section 5.1) is to determine whether protected electrical equipment is required, if so refer to BS EN 60079, Part 14 (33), Explosive atmospheres. Electrical installations, design, selection, and erection.
A responsible person shall carry out a Fire Safety Risk Assessment on all gas cylinder storage areas to determine the hazard and the risk associated with a fire originating from a gas cylinder and/or a fire impacting on a gas cylinder(s). The findings from which are to be incorporated into the Site Fire Safety Management Plan that is to be implemented and maintained. As necessary, advice should be sought from the Fire and Rescue Service. The risk control measures identified shall be incorporated into the construction of the gas cylinder store(s).
The location of each gas cylinder store shall be recorded within the site’s hazardous locations record. This record should include information on the products stored, their maximum quantities and their hazardous classification. This should be updated on a regular basis. This is to be made available to the emergency services in the event of an incident.
All personnel who are required to handle and store gas cylinders shall receive suitable information and instruction regarding the hazards associated with gas cylinders and the gases being stored, and provided with the necessary skills and knowledge to carry out their job safely.
It is the duty of the employer to ensure their persons are adequately trained and to establish competency. It is recommended that a training programme is carried out under a formalised system where an acceptable level of competency has to be achieved. Records shall be kept of the training provided and the competence level achieved. The training programme shall make provision for periodic re-training.
Training should be reviewed and/or updated following:
All persons engaged in the storage of gas cylinders shall have training commensurate with their responsibilities and should include, but not confined to the below subjects.
Specific training and certification requirements are required for persons handling fluorinated gases.
If you require further help from the team at Chemstore then get in touch with one of our sales engineers today!
The Grit Guard Bucket Dolly features 5 heavy-duty urethane casters that last longer and roll smoothly over cracks.
Two of the casters lock, holding your bucket in place even on steep inclines.
Rugged Bucket Dolly supports up to 250 pounds and is securely held in place with three thumb screws.
Dolly will fit most 3.5 gallon, 4 gallon, 5 gallon and 6 gallon bucket.
Grit Guard Bucket Dolly allows for smooth bucket maneuvering.
Flammable materials are substances that can ignite easily and burn rapidly. They can be common materials that are at most work sites in gas, liquid and solid forms. Proper flammable material storage needs to be followed to avoid an accident in the workplace. Some flammable materials which pose a risk include:
Gases — Natural gas, propane, butane, methane, acetylene, carbon monoxide, hydrogen sulphide. Flammable gases usually have with a lower explosive limit of less than 13% in the air or have a flammable range in air of at least 12%. For example, butane is a flammable gas because its lower explosive limit in the air is 20%. Carbon monoxide has a lower explosive limit of 13% and an upper explosive limit of 74% in air, it is flammable over a range of 61%.
Liquids — Many solvents such as acetone, alcohols and toluene, paints and paint thinners, adhesives, degreasers, cleaners, waxes and polishes. Flammable liquids have a flashpoint below 37.8⁰C (100⁰ F).
Solids — Some types of coal, pyrophoric metals (metals that burn in contact with air or water, such as sodium and potassium) solid wastes that are soaked with flammable liquids (rags, paper, spill clean-up products) and matches.
To read more about our best-in-class flammable materials storage, read up on our Fireavault range here.
For a fire to occur, three elements must come together at the same time and in the right proportions, fuel, heat (ignition source) and oxygen. Remove any of the elements and the fire will go out.
The “fire triangle” is commonly used as a model to understand how a fire starts and how it can be prevented.
Fuel — Fuels are flammable or combustible materials and can be gases, liquids or solids.
Heat — These are ignition sources and include an open flame, lit cigarette and sparks (such as from electrical current and static electricity shorts). A chemical reaction that creates heat can also ignite a fuel and oxygen mixture.
Oxygen — The most common source of oxygen is air, but oxygen can also come from chemicals called oxidizers. Examples of common oxidizers are some types of acids and chemicals such as chlorine, chlorine dioxide, potassium permanganate and potassium chlorate.
The spread of fire is also dependant on a fourth factor, the chemical chain reactions that occur after the fire is started. Fire prevention consists of making sure that the three legs of the fire triangle never meet. It is important to note that a fire will not always start even when the legs of the triangle meet unless all three elements are present in the right amounts. For example, vapours from a flammable liquid must be mixed with a certain amount of air and exposed to the right amount of heat to ignite and burn. Once vapours from a flammable liquid have ignited, the flames may “flash-back”. This means the flames travel back, through the vapour air mixture, to the container or source of the flammable liquid. This can create an explosion. Most flammable liquids produce vapours that are heavier than air. Some flammable gases are also heavier than air. These gases and vapours can spread a considerable distance along the ground or floor and be ignited by a distant spark or flame or source of heat. Certain chemicals such as organic peroxides (e.g. benzoyl peroxide) contain both fuel and oxygen.
The employer must develop work procedures for the use and storage of flammable materials and ensure workers are trained on these procedures. Because of the potential fire hazard, the employer will also need to have additional procedures in place to deal with fires and spills.
Work procedures should address:
In general, flammable materials must not be stored near exits, electrical equipment or heating equipment. They should always be stored in a separate, well-ventilated storage area, away from potential sources of ignition. If the material is removed from its original container, it must be placed into a container that is appropriate for flammable materials.
When flammable liquids are transferred from their original container (one they were purchased in), or from bulk storage such as a drum or tank, the proper type of portable container must be used. Containers that are approved for the use and storage of “portable quantities” are usually made of metal or plastic, are vapour-proof and have:
Portable containers must be properly labelled. The labelling should include the following information:
When individual containers of flammable liquids are not in use and are stored inside a building, they should be stored in a storage cabinet. The European Standard EN 14470-1 was implemented in April 2004 and has since been published as a national standard in many European countries as the Netherlands, France, Ireland, Spain, UK, Italy etc.
Since the 1st of January 2005, the former German Standard DIN 12925-1 can no longer be taken into consideration for testing Safety Storage Cabinets.
Test and construction requirements, compared to the DIN 12925-1, have become stricter and in some details stated more precisely. The following points describe the basics and main safety, test and construction requirements.
The range of applications
– The standard specifies the performance required of the design and fire resistance of safety storage cabinets used for storing flammable liquids in working areas.
The principal safety requirements
– Minimisation of the fire risk associated with the storage of flammable materials.
– Protection of the contents of the cabinet in the event of a fire for a known (and tested) period of time.
– Minimisation of the fumes released to the working environment.
– Retention of any possible leakage within the cabinet.
– Provision of enough time, in the event of a fire, for personnel to leave the room,
and sufficient time for fire service personnel to enter the building before the
stored materials turn a small fire into an uncontrollable blaze.
– In the event of a fire the cabinet must ensure that, over a period of time defined by the manufacturer (but in any event at least 15 minutes), its contents do not present an additional risk that the fire will spread.
– The cabinet doors must close entirely, starting from any position (closing time max. 20 seconds).
– Immobilising equipment fitted must release the locked doors at a temperature of 50 (-10) °C.
– Avoiding the risk of injury: the closing force of the doors must not exceed 100 N.
– One-handed operation must be possible, and the doors must close entirely even if open and locked.
Side and rear walls
– The side and rear walls of the cabinet must have the same thickness and comparable structures.
Air inlet and outlet openings
– The cabinets must have openings for air inlet and outlet (for connection of the cabinet to an exhaust system).
– The ventilation openings must close automatically at a temperature of 70 °C.
Storage locations (shelves or drawers)
– Storage surfaces must be able to support the loading specified by the manufacturer throughout the test in the furnace. Design evidence of the load-carrying capacity of shelves and drawers in the event of fire based on EN 1365 (fire resistance tests for self-supporting components).
Spill containment sump
– The spill containment sump must retain its ability to function after the fire resistance test. This is to be checked visually by filling the spill containment sump with water
– Must be investigated by tests on a design sample.
– The fire-resistant cabinet is exposed to flames in a suitable furnace.
– The doors, walls and ceiling of the cabinet being tested must be exposed to the same heating conditions.
– Cabinets must be tested as free-standing single cabinets. The example being tested must be positioned with its rear wall at least 100 mm from the furnace wall.
– The flame exposure is carried out under the standard temperature curve of BS EN 1363-1.
– The temperature rise is measured inside the cabinet.
– The cabinet must then be classed as type 15, 30, 60 or 90, according to the time that has elapsed before the temperature rose by 180K.
At some work sites, there are many different types of flammable materials or large volumes of particular materials used. At these sites, flammable materials may be stored in large containers (drums or tanks) or there may be a specific flammable material storage room. The specific requirements for above ground storage tanks and storage rooms is HSg51.
|Quantity Stored (L)||Distance (M)|
|Up to 1,000||2|
|1,000 to 100,000||4|
To prevent fires, flammable materials must be properly managed in the workplace. There are three main ways to prevent fires:
Limit the amounts of flammable and combustible materials
Provide proper ventilation to ensure flammable vapours do not accumulate
Control ignition sources
Static electricity is an electric charge that cannot move. It is created when two objects or materials that are in contact with each other are separated. While the objects are in contact, the surface electricity charges try to balance each other. When the objects are separated, they are left with either an excess or shortage of electrons, causing them both to become electrically charged. If these charges do not have a path to the ground, they are unable to move and becomes “static”. If static electricity is not quickly removed, the charge will build up. Eventually, it will develop enough energy to jump as a spark to some nearby less highly charged object. In an explosive or flammable atmosphere, the spark can set off an explosion or fire. The danger is greatest when flammable liquids are being poured or transferred.
Static electricity can be produced by:
Static electricity can be controlled by:
Bonding and grounding are techniques that are used to prevent sparks (a source of ignition) from being created when liquids are transferred between containers. Bonding is when there is an electrical connection between two or more conductive containers. Bonding ensures that the containers have the same electrical charge. Without a difference in charge, a spark cannot be created that jumps from one container to another. Bonding does not eliminate the static charge which is why it is used in combination with grounding. A container is grounded when there is an electrical connection between the container and the earth. Grounding quickly drains the static charge away.
If you have any questions about our Firevault range or flameproof cabinets, get in touch today by calling, emailing or using the Live Chat feature on the bottom left corner of your screen.