If you’re storing Class 3 Flammable Liquids in your business, one of the questions you may have to consider is, ‘How many flammable cabinets can I have in one area?’ And while there is no simple one-word answer to this query, there are some variable factors in your workplace that will determine how many cabinets you can install in a single work area. This blog brings together some key considerations that will help you understand the requirements for flammable liquids storage — and assist in your flammable cabinet installations.
Let’s get started by reviewing the cabinet location requirements of flammable liquids requirements as per the Australian Standard AS 1940:2017 – The storage and handling of flammable and combustible liquids.
Aggregate Quantities
The standard states that indoor flammable cabinets must not exceed 850 L capacity. It also lists aggregate capacity limits for flammable liquid storage.
AS 1940:2017 explains:
4.9.6 Cabinet location
(e) The aggregate capacity of cabinets shall not be greater than—
(i) 850 L per 250 m2 on a ground floor area; or
(ii) 250 L per 250 m2 on other floors.
(f) Each aggregate quantity given in Item (e) shall be separated by at least 10 m.
Therefore, the first point that you need to consider is the size of your cabinet (maximum 850 L). Once you’ve determined your cabinet size and chemical capacities, you’ll need to decide what and what floor you’re going to be installing your cabinets on.
Indoor flammable cabinets must not be larger than 850 L. There are specific requirements that limit the aggregate capacities of flammable liquids stored indoors.
You can install a larger volume of flammable liquids if you have a ground floor location. However, your business is required to keep each aggregate quantity of Class 3 Flammable Liquids separated by a distance of at least 10 metres.
Cabinets Larger Than 250 L
There are additional requirements for cabinets that hold more than 250 L of flammable liquids — and this will limit the amount of cabinets that you can install in one area.
The standard explains in Section 4.9.6:
Cabinet location
(b) Cabinets having a capacity greater than 250 L shall not be installed in residential or accommodation buildings, commercial buildings, hospitals, aged care buildings or school buildings.
(c) Cabinets having a capacity greater than 250 L shall only be installed on floors that have direct access from street or ground level.
(d) Cabinets having a capacity greater than 250 L shall not be placed nearer than 3 m to any wall that is common with another room, unless that wall is 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.
Due to the increase in risk with storing larger volumes of hazardous chemicals, cabinets that have a capacity larger than 250 L must not be installed in buildings including hospitals or schools. These cabinets must be installed on a ground floor or in an area that has direct street access. This allows a swift evacuation as well as easy movement for emergency crews in the event of a fire or explosion.
Flammable cabinets that hold more than 250 litres of chemicals are subject to the additional cabinet location requirements of AS 1940:2017.
You will also have to consider that these larger cabinets can’t be installed close to common walls, unless it’s concrete or masonry to ceiling height or 3 metres above the top of the cabinet – whatever is the smaller measurement. You’ll also need to position the cabinet with a 3 metre space on each side.
Keep in mind that there are many other factors that you’ll need to consider before you choose your exact cabinet location. We’ll discuss these in detail below.
Emergency Access
A key requirement of AS 1940:2017 is ensuring the location of the cabinet allows for escape during an emergency.
(a) Cabinets shall be located so that they do not impede escape in an emergency.
This means that you must position your flammable liquids cabinets so that they don’t inhibit the movement of personnel that is moving towards an emergency exit. This includes avoiding locations such as walkways, hallways and stairwells.
When selecting locations for multiple cabinets, make sure that you’re not impeding escape during an emergency situation such as a fire or explosion.
Workplace Exposure Standards
To maintain a healthy and safe environment for the people in your organisation, you must adhere to the workplace exposure standards that were developed by Safe Work Australia.
Class 3 Flammable Liquids (or any chemicals for that matter) emit hazardous vapours which contribute to airborne concentrations of that chemical. When the legal limit of airborne concentrations in the breathing space of workers is exceeded, it can cause human harm and increase the risk of fire or explosion.
You must ensure that the volume of flammable liquids that you store don’t emit vapours which are in excess of the workplace exposure standards.
Vapours can be emitted when flammable liquids are being used or decanted. Therefore, you must keep your stored flammable liquids in containers (with lids securely in place) to avoid vapours building up within the cabinet.
However, if the workplace exposure standards are exceeded, you must implement measures to decrease the concentration of vapours in your workplace.
This may include:
- Implementing good housekeeping practices for your flammable cabinets ie not overloading the cabinet, cleaning up spills immediately, making sure containers are tightly capped
- Installing a mechanical ventilation system for your cabinet/s to disperse hazardous vapours
- Reducing the volume of chemicals that you store in the specific workspace, so the vapour emissions from the flammable liquids are reduced
Spill Bunding
Regardless of how many cabinets you have in your workplace, or what volumes of flammable liquids that you carry, you must provide adequate spill containment for your Dangerous Goods.
While compliant cabinets are equipped with liquid-tight spill containment sumps in the lower compound, there are some incorrect practices you should avoid if you want to maintain the integrity and capacity of your bunding.
Compliant flammable liquids cabinets offer liquid-tight spill containment with a sump that must be maintained so no leaks or spills accumulate in the cabinet.
Implement these practices to keep your spill bunding compliant:
- Don’t store anything in the spill containment sump — that includes flammable liquid containers, combustible materials such as paper manuals or paintbrushes, or everyday work items such as tools.
- Make sure your cabinet is regularly inspected for any chemical leaks or spills — this will allow your staff to adhere to operating procedures
- All contents of the spill bund should be cleaned out as soon as a spill or leak occurs — this is so the capacity of the bund remains compliant.
- Remember that any cleaning items such as rags or sponges will be soaked with flammable liquids — so make sure these are handled and disposed of in a safe way.
You may also wish to implement additional bunding to protect your organisation. Options you may consider will depend on your risk assessment of your work areas. Options may include floor bunding for your workspace or drum handling and dispensing equipment to avoid chemical spills when transferring flammable liquids.
Ignition Sources
If you’re storing flammable liquids indoors, one of the most important things to remember is that your safety cabinet must never be installed close to an ignition source.
The Australian Standard AS 1940:2017 explains:
4.9.7 Exclusion of ignition sources
There shall be no ignition sources within the cabinet.
Where flammable liquids are stored, ignition sources shall be excluded from the area outside the cabinet to a distance of 3 m measured laterally, and from floor level to a height of 1 m above any opening in the cabinet, including the door, or a distance determined in accordance with AS/NZS 60079.10.1.
Ignition sources can be anything from hot work to a power point or cigarette lighter that’s been brought into the workplace.
When installing flammable cabinets, you must ensure that they are not positioned within 3 metres of an ignition source.
Sources of ignition can be thermal, electrical, mechanical or chemical, so it’s crucial your staff are trained to identify and eliminate any potential ignition sources from your work area.
Installing Multiple Flammable Cabinets
The logistics of installing multiple flammable liquids cabinets into one workspace will require careful planning. Make sure you look at the size of your workspace, the duties performed in that area and how the space is configured. Mapping out the installation of multiple cabinets before they’re delivered is a time-saving tip that will make the process a smoother one.
If you’d like to learn more about the safe storage of Class 3 Flammable Liquids, we have a helpful eBook that will guide you through the whole process. Essential Considerations When Storing Flammable Liquids Indoors will introduce you to our 4-STEP risk management methodology IDENTIFY – ASSESS – CONTROL – SUSTAIN and give you expert tips on how to select, install and maintain your flammable cabinets. Get your free copy now.
