Class D fires involve combustible metals, such as magnesium, titanium, potassium and sodium as well as pyrophoric organometallic reagents such as alkyllithiums, Grignards and diethylzinc. These materials burn at high temperatures and will react violently with water, air, carbon dioxide and/or other chemicals.
Class D extinguishers typically require a large amount of agent (several inches) to complete encapsulate and smother the fire. These extinguishers are designed to deliver the agent so it can form the necessary layer and the agents are chosen to be inert to most reactive metals.
If you have more typical fire threats, go back to the By Class page to view your other class options.
Among our customers who are preparing for potential lithium ion (LiON) battery fires, the most popular extinguishing agent is Lith-X which is a free-flowing graphite material. Graphite has exceedingly high thermal conductivity and helps pull heat away from the fire and it has excellent resistance to heat.