Solvents are substances that are used to dissolve a solute, resulting in a solution. A flammable solvent is a solvent that is volatile and is capable of giving off enough flammable vapours to ignite in the presence of an ignition source at temperatures below 60 °C. Flammable solvents are extremely useful and they are used in a range of industries including: chemical, pharmaceutical, gas and oil industries.
Some examples of flammable solvents include:
- Paint thinners
- Methyl acetate
- Ethyl acetate
Flammable solvent storage requirements
As flammable solvents such as paint thinners, acetone and toluene are extremely flammable, they must be stored and handled in a safe and compliant manner to reduce the risk of workplace injuries. Flammable solvents are extremely volatile and they give off a lot of flammable vapours. If the flammable vapours from a flammable solvent came into contact with an ignition source, it would cause a severe fire that would harm people, property and the environment. To reduce the risk of workplace fires all flammable solvents must be stored and handled in full conformance to AS1940. AS1940 is the Australian Standard that outlines the storage and handling requirements for Class 3 - Flammable Liquids. This standard outlines different storage requirements for indoor storage and outdoor storage of flammable solvents.
If your organisation uses smaller quantities of flammable solvents, they can be safely stored indoors. AS1940 outlines that small quantities of flammable solvents can be safely stored indoors using a flammable storage cabinet. The maximum quantity of flammable solvents that can be stored in an indoor flammable liquids storage cabinet is 850L. AS1940 also states that no more than 850L of flammable storage cabinets can be located in each 250 m2 of workshop floor space.
The design and construction requirements for flammable liquids storage cabinets are very strict. The design requirements include:
- Double walled sheet steel construction for the roof, floor, doors and wall of the cabinet. This double walled sheet steel construction must have at least a 40mm air gap between the walls.
- Self-closing, close-fitting doors that automatically hold shut with catches at two or more points.
- The base of the cabinet must form a liquid tight sump that is at least 150 mm deep. This sump must be designed in a way that prevents packages from being stored within.
- All shelves within the cabinet must be perforated to allow for free air-movement.
- All gaps around the doors of the cabinets must be sealed to prevent the spread of flames and heat radiation.
- The materials of any components on the cabinet that are critical to its structural integrity must not melt at temperatures below 850 °C.
- Each flammable storage cabinet must be marked with a sign:
- No Smoking No Ignition Sources Within 3m
- Class 3 Flammable Liquids Diamond
An example of a flammable liquids storage cabinet that is manufactured in full conformance to AS1940 is shown below:
If your organisation needs to store more than 850L of flammable solvents per 250 m2 of floor space, you will have to store these larger quantities of flammable liquids solvents outdoors. Storing larger quantities of flammable liquids outdoors reduces the risk of harm to people and property in the event of a workplace fire. The requirements for outdoor storage of Class 3 - Flammable Liquids differ from the requirements for indoor storage of flammable liquids. Some of the differences include; larger spill containment capacity, natural ventilation provisions, heavy duty construction requirements and the provision of safety showers and eyewash stations. The design and construction requirements for outdoor flammable liquids storage containers are outlined below.
Spill containment requirements
The spill containment capacities required for outdoor flammable liquid storage containers differ depending on the quantities of flammable liquids stored inside the container. These differing capacities are outlined below:
Facilities storing less than 10,000L
Spill containment capacity = 100% of the largest package within the store + 25% of the aggregate capacity of the store.
Facilities storing between 10,000L - 100,000L
Spill containment capacity = 100% of the largest package within the store + 25% of the aggregate capacity of the store + 10% of storage capacity between 10,000L and 100,000L.
Facilities storing more than 100,000L
Spill containment capacity = 100% or the largest package within the store + 25% of the aggregate capacity of the store + 10% of storage capacity between 10,000L and 100,000L + 5% of the storage capacity exceeding 100,000L
To avoid the risks of workplace fires, all outdoor flammable liquids storage containers must be ventilated to keep the concentration of the flammable vapours below the workplace exposure standards. An efficient and effective way to ventilate flammable liquids storage containers is to have a natural ventilation system. AS1940 states that a natural ventilation system on a flammable liquids store can be achieved by having two walls of fixed louvers open to the air.
Provision of safety showers and eyewash stations
As well as being extremely flammable, flammable solvents are also very toxic. If flammable solvents are ingested, it can result in severe intoxication which can lead to severe injury. Because flammable solvents are very toxic, they will cause a lot of irritation if they come into contact with your eyes or skin. If your eyes are exposed to large quantities of solvent, your eyesight could be permanently damaged. To avoid the risk of eye damage, all outdoor flammable liquids storage containers must be located next to emergency decontamination facilities. AS1940 states that all flammable liquids storage facilities must have a eye wash station within 10 metres but no nearer than 2 metres. When the outdoor flammable liquids storage container is storing more than 2000L of flammable solvents, a safety shower must also be located within 10 metres but not nearer than 2 metres.
As flammable solvents pose many risks upon the people, property and the environment of your organisation, it is very important that you store and manage your flammable solvents in a safe and compliant manner. Flammable solvents can be safely stored by following the requirements outlined in AS1940. If you would like more information on how to reduce the risk associated with flammable liquids and other flammable solvents, download our FREE eBook by clicking on the image below.