The goals for hydrogen control in nuclear power plants are to design countermeasures that allow operators to avoid deflagration-to-detonation transition (DDT) and to ensure the survivability of equipment. These goals could be achieved by using a quenching mesh. Flame arrest tests are carried out using a quenching mesh with a 0.3-mm gap distance. When the quenching mesh is installed between compartments, the quenching mesh plays a role in flame quenching below 1.8 bars of the initial pressure and less than ~1.6 m/s of the flame velocity. Therefore, if the quenching mesh is properly installed in the containment, the flame could be arrested within the mesh boundary, resulting in the prevention of DDT and the survivability of equipment. Flame-quenching criteria are suggested using the expansion ratio, the initial air pressure, and the flame velocity.