Flammable solvents are common chemicals that are widely found in industries such as pharmaceutical, chemical, gas, oil and manufacturing. However, as flammable solvents are recognised as Class 3 Liquids, they must be handled and stored in a way that reduces risk. If flammable solvents are stored in certain conditions, they can be capable of emitting enough flammable vapours to ignite in the presence of an ignition source. The incorrect storage of solvents can also result in harm to workers, such as hazardous vapours causing asphyxiation or spilt chemicals burning the skin or permanently damaging eyesight. In this blog, we’ll be detailing the requirements for flammable solvent storage — and explaining how you can safely store these chemicals in your own organisation.
Examples Of Flammable Solvents
Solvents are potent chemicals which are used to dissolve a solute, which results in a solution. There are many different types of flammable solvents that are commonly used in the workplace.
Some examples of flammable solvents include:
- Paint thinners
- Methyl acetate
- Ethyl acetate
What Are The Risks Associated With Flammable Solvents?
As solvents are extremely flammable, they must be stored in a safe and compliant manner to reduce the risk of workplace injuries and property damage.
If flammable solvents aren’t stored correctly, it could result in an:
- Uncontrolled chemical spill
- Fire and/or explosion
- Chemical burns
- Acute health issues
- Destruction of property and vehicles
- Toxic fumes in the event of a fire
- Soil and water contamination
- Harm to wildlife and/or farm animals
Flammable solvents are highly volatile chemicals which can emit large quantities of flammable vapours. While some Class 3 DG only ignite at certain temperatures, flammable solvents can cause a fire or explosion if the ambient temperature is below 60 °C – which is considered a low ignition temperature. Keep in mind that many workplaces will have chemical storage and handling areas that are within the temperature range conducive to flammable vapour ignition.
Due to the high risk of ignition, care must be taken to ensure that flammable solvents are handled and stored in such a way as to reduce the concentration of flammable vapours and the likelihood and impact of a chemical spill. They must also be segregated from ignition sources and other incompatible substances and materials. Consideration must also be given to ensure that flammable substance stores are located away from protected places and public places, so risk to the local community is minimised.
Flammable Solvent Storage Requirements
To reduce risk, flammable solvents must be stored and handled in full conformance to AS 1940:2017 – The storage and handling of flammable and combustible liquids.
AS 1940 is the Australian Standard that outlines the requirements for Class 3 Flammable Liquids, such as flammable solvents. This Standard offers precise details of the storage requirements that relate to the indoor and outdoor storage of Class 3 flammable substances.
We’ll go into further detail about these requirements in the below section of the blog.
To determine your flammable solvent storage requirements, refer to the Australian Standard AS 1940:2017.
Indoor Storage Of Solvents
If your organisation uses smaller quantities of flammable solvents, you may choose to store them safely indoors. When considering indoor storage for your solvents, a flammable storage cabinet is a compliant option.
However, there are restrictions as to what quantities of Class 3 liquids are stored in flammable cabinets. There are also requirements that affect the location of the cabinet itself.
The maximum quantity of flammable solvents that can be stored in an indoor flammable cabinet is 850 L. In addition to this, no more than 850 L of flammable storage cabinets can be installed per 250 m2 of workshop floor space.
Any flammable cabinet must be installed in a position that does not impede emergency evacuations.
Larger Capacity Cabinets
Larger capacity cabinets, that are greater than 250 L, must only be installed on floors with direct street or ground floor access. They should also not be placed closer than 3 metres to common walls —unless the wall has been constructed of concrete or masonry (to ceiling height or 3 m above the top of the cabinet, whichever is less, and 3 m to either side of the cabinet).
Flammable Cabinet Construction Requirements
The design and construction requirements for flammable liquids storage cabinets are very strict and include specifications such as:
- 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 signage:
- No Smoking No Ignition Sources Within 3 metres
- Class 3 Flammable Liquids Diamond
Your flammable liquids storage cabinet should be manufactured in full conformance to AS 1940 to meet these stringent safety requirements.
Features of a compliant cabinet include signage, non-combustible construction materials, liquid-tight spill containment sump and perforated shelving.
Outdoor Storage Of Solvents
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 chemical spill or workplace fire.
The requirements for outdoor storage of Class 3 Flammable Liquids differ from the requirements for indoor storage of flammable liquids.
When storing flammable solvents in the outdoor environment, you must ensure that you meet the requirements of AS 1940.
Some of the differences include:
- Larger spill containment capacity
- Natural ventilation provisions
- Heavy duty construction requirements
- Provision of emergency decontamination equipment
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: