13.5.22 Helideck floodlights should be located
so as to avoid glare to pilots, and provision should be made for periodically
checking their alignment. The arrangements and aiming of floodlights
should be such that helideck markings are illuminated and that shadows
are kept to a minimum. Floodlights should conform to the same height
limitations specified in paragraph 13.5.20 for perimeter lights.