A mezzanine is, strictly speaking, an intermediate floor in a building which is partly open to the double-height ceilinged floor below, or which does not extend over the whole floorspace of the building. However, the term is often used loosely for the floor above the ground floor, especially where a very high original ground floor has been split horizontally into two floors.
Employees in material handling and manufacturing are often at risk to falls when they are on the job. Recent figures show approximately 20,000 serious injuries and nearly 100 fatalities a year in industrial facilities. Falls of people and objects from mezzanines are of particular concern.
In many industrial operations, openings are cut into the guardrail on mezzanines and elevated work platforms to allow picking of palletized material to be loaded and unloaded, often with a fork truck, to upper levels. The Occupational Safety and Health Administration (OSHA) and International Building Council (IBC) have published regulations for fall protection and The American National Standards Institute (ANSI) has published standards for securing pallet drop areas to protect workers that work on elevated platforms and are exposed to openings.
In most cases, safety gates are used to secure these openings. OSHA requires openings 48 inches or taller to be secured with a fall protection system. Removable sections of railing or gates that swing or slide open would be used to open up the area and allow the transfer of material, and then close once the material is removed. However, current ANSI standards require dual-gate safety systems for fall protection.
