Light-emitting systems for headgear

A light emitting unit removably attachable to a hardhat by pressing the light emitting unit onto the hardhat, the light emitting unit comprising:

• a rigid annular housing sized and shaped to circumferentially surround the hardhat;
• at least one lens coupled with the rigid annular housing to collectively define an interior housing cavity;
• a plurality of lighting elements supported within the interior housing cavity and arranged to generate light that projects radially outwardly away from the light emitting unit when energized;
• an electrical power source electrically coupled to the plurality of lighting elements to provide energy to selectively illuminate the plurality of lighting elements;
• and
• an attachment mechanism projecting inwardly from the rigid annular housing and being configured to engage an exterior surface of the hardhat and to hold the rigid annular housing offset from the exterior surface of the hardhat.