Ash from a Safety Flare from Washington, D.C.

Ash from a Safety Flare. Used in traffic and pedestrian control efforts during the Presidential Inauguration ceremonies, Washington, D.C. 2009

Flares produce their light through the combustion of a pyrotechnic composition. The ingredients are varied, but often based on strontium nitrate, potassium nitrate, or potassium perchlorate and mixed with a fuel such as charcoal, sulfur, sawdust, aluminum, magnesium, or a suitable polymeric resin. Flares are used for distress signals (especially in marine emergencies) and for extreme traffic conditions, such as the crowds attending various celebrations and rituals connected with, or simultaneous with, the Presidential Inauguration Ceremonies, which in January of 2009, saw one of the largest crowds ever assembled in the United States Capital’s history.

(See also: Metal Skeleton and Red Paper Remains of a Safety Flare, Washington, D.C.)