The "Clean Your Boots" sign is a health and safety sign that reminds the individual to clean off boots to avoid possible risks associated with bringing certain chemicals, debris or substances either in, or out, of certain spaces and workplaces. The sing pictures a pair of industrial boots being hosed down, suggesting the appropriate workplace etiquette.  

The sign is best displayed at entrance and exit points of certain spaces, reminding the individual to not bring debris in or out of the designated area to avoid the associated safety risks.