Green man is a legendary pagan deity who roams the woodlands of the British Isles and Europe. He usually is depicted as a horned man peering out of a mask of foliage, usually the sacred oak.
The "green man" in pyrotechnics is coined for a 1600s pyrotechnician who would wear green leaves and mud to both protect himself from sparks and hide himself from the crowd while igniting fireworks. The green man is the symbol of the Pyrotechnics Guild International.