Solid substances that produce a flammable gas when wet or react violently with water. Known examples include sodium, calcium, potassium, lithium and calcium carbide. Please note, attempting to put out a fire involving dangerous when wet materials with water will only make the situation worse. Special “Class D” fire extinguishers are required for use with dangerous when wet substance

Handling and Storage Guidelines

Similarly, to flammable, pyrophoric, and self-heating materials, the same handling guidelines applies to dangerous when wet materials. It is important to note that any paper toweling, Kim wipes, gloves, etc., that have come into contact with these materials need to be quenched with water before disposal. When working with these materials, make sure that all glassware and equipment is completely dry before use. An SOP and Risk Assessment should be prepared for each process involving pyrophoric or water-reactive materials and always perform a dry-run without any chemicals of the experiment.

For storage, always check Section 7 of the SDS for storage guidelines. Keep the container dry and store in appropriate cabinets. Never store near any water sources.