Guard Services USA personnel constantly scan the entire area with their eyes. By covering their eyes, sunglasses prevent attackers from spotting the guard's eyes and determining how to attack. It improves the security officers' ability to detect sudden movement.
What tools do security guards have on them?
Armed security guards can carry batons, pepper spray, tear gas, and even firearms, depending on the job they are hired to do and the industry they work in. Two-way radios for communication, handcuffs for confinement, flashlights, and a smartphone are additional tools that an armed guard might carry.