This text is intended as an introduction to the subject, and should not be considered definitive or exhaustive.
What is the difference between flammability and combustibility?
The flammability of a liquid is generally assessed from its flashpoint. The flashpoint is the minimum temperature at which a saturated vapour will ignite. As ignition is usually initiated through vapour, then spreads to the liquid, this is an important metric.
As the flashpoint temperature increases, and volatility decreases, there is less chance of vapour ignition. So we turn our minds to the auto-ignition, or combustibility of the bulk liquid. This is the auto-ignition temperature.
So the two are related…flammability, vapour…and combustibility, liquid.
What are the flammability classifications?
Flammable liquids
categorised under CLP will be clearly labelled as:
Category 1: flashpoint <23 °C and initial boiling point ≤35 °C.
Category 2: flashpoint <23 °C and initial boiling point >35 °C.
Category 3: flashpoint ≥23 °C and initial boiling point ≤60 °C.
Non-flammable combustible liquids with a flashpoint above 60 °C.
What to consider when storing flammable liquids?
The overall working environment should be taken into consideration. Other pertinent factors such as sources of ignition, ventilation, viscosity, surface area, physical environment and method of application all play their part.
How do you store flammable liquids?
Flammability and combustibility are important safety considerations when storing industrial cleaning chemicals. While safe when used as directed, a risk assessment should be undertaken before introducing combustible materials to the workplace. The risk assessment will consider both the material and the working environment and inform how on how best to store flammable liquids.
The HSE recognise that flammable liquids are sometimes essential in the workplace.
The recommended maximum quantities that may be stored in cabinets and bins are:
- No more than 50 litres for highly flammable liquids, and those with a flashpoint below the maximum ambient temperature of the workroom/working area;
- No more than 250 litres for other flammable liquids with a higher flashpoint of up to 60 °C.
Non-flammable products
Did you know we also stock a range of non-flammable cleaning chemicals? Aqueous products (water based) are non-flammable and non-combustible. Browse the range here.