mcr EXi - overpressure system for preventing smoking of evacuation routes

ITB Technical approval AT-15-9287/2014

ITB Certificate of conformity CZ-ITB-2337/W

Domestic Declaration of performance HW/03/2017


Protection from smoking of vertical evacuation routes is an important element of the entire fire safety system of the building. mcr EXi overpressure smoking prevention system installed on staircases provides added safety of building users. The system comprises suitably designed sets of devices that, by co-operating with each other, prevent smoking of protective zone by creating increased pressure.


mcr EXi system includes:

  • inflow sets: GZN top air supply unit, DZN bottom air supply unit
  • release sets: GZU top air bleed unit, DZU bottom air bleed unit
  • mcr Omega system supply and control units
  • ventilation equipment: grating, air intakes and wall ejectors, insulated air dampers

Configuration and quantity of individual system components is dependent on the requirements of fire scenario, specifics of the building, and the design of its staircase, elevator shaft, or other protected space.

  • wide adjustment range allows to adapt the system to actual conditions within the building (adjustable inflow units and bleed damper presets)
  • the system mostly operates mechanically; it is therefore resistant to failure of electronic systems
  • quicker system response to changes in fan capacities thanks to mechanical bleed dampers
  • intuitive operation - ease of designing the system and choosing devices
  • various mounting methods
  • air supply units series of types available: DZN/GZN 450, DZN/GZN 630, DZN/GZN 710, DZN/GZN 800
  • units making: rounded housing
  • units installation type: vertical or horizontal
  • units installation location: outdoor or indoor
  • units capacity up to 40 000 m3/h
  • compression up to 500 Pa
  • rotation speeds n = 750; 1000; 1500; 3000 RPM


  • release sets series of types available: GZU/D 1300x1300 and 800x800, DZU/GZU 500x500 up to 1300x1300 mm
  • sets installation type: wall-mounted, duct-mounted, roof-mounted
  • sets installation location: outdoor or indoor
  • sets air flow rates up to 27 000 m3/h
  • Public buildings
  • Commercial buildings
  • Residential buildings

Choosing mcr EXi system allows the investor to obtain significant reductions of requirements contained in the "Technical conditions for buildings and their location", including:

  • lowering of fire resistance class of building
  • enlargement of permissible fire zones
  • extension of evacuation routes