The GateKeeper's dual reciprocating gate increases safety at the edge of a mezzanine platform by keeping one gate closed at a time. The design meets applicable OSHA, ANSI, and IBC standards. The Saf-T-Latch prevents workers from raising the gate from inside the work zone and possibly falling off the mezzanine. The link-bar design ensures both gates work in unison. The unit is available in automatic and manual designs.