Traditional extinguishers are not only ineffective but dangerous to use against metal fires. For metal fires, the class D fire extinguisher is used instead. Effective against lithium, sodium, magnesium, calcium, zinc and aluminium fires when in the form of powder or swarf.
To prevent splashing of the molten metal, these extinguishers are equipped with a low velocity applicator cup 1.5m in length. This provides a degree of safety to the person operating the extinguishers.
The unique lance applicator is designed to allow the powder to fall gently over the fire to prevent burning material from spreading.
Class D Fires
The Singapore Standards 578 defines class D fires as
Class D fires are fires involving combustible metals e.g. potassium, magnesium, titanium, sodium, lithium and zirconium.
Very importantly, all Class D metal fires are considered as special hazard. The operator attempting to put out class D fires must be specifically trained to do so. These fires are incredibly challenging even for professional fire fighters. To add on to the complexity, a Class D fire extinguisher may only be able to put out specific metal fires but not others. Usually, the fire fighting agents for Class D fires will starve the fires of their oxygen by a sealing or burying action. The ABS 12KG Class D fire extinguisher , with its applicator, allows the operator to safely put out Class D fires.
How to use a fire extinguisher?
Before you use a fire extinguisher, always ensure you have an escape route. If you have to use a fire extinguisher, do so at a safe distance. When in doubt, always choose to run. Even professional fire fighters in full fire resistant suits have been trained to never put their own lives at risk.
Always remember PASS. You can also read the instruction label on the fire extinguisher.
1. Pull the safety pin
2. Aim at the base of the fire
3. Squeeze the lever and allow powder to gently fall onto the metal fire. *
*This version of PASS is slightly different from usual. The operator must gently drop the class D powder onto the metal fire. Any attempt to violently move the burning metal will cause the fire to become larger.