Fire Dampers Ventilation Ductwork

Part 9 and htm 2025 ventilation in healthcare premises.

Fire dampers ventilation ductwork.

Ventilation ductwork should comply with bs 5588. However two hour fire rated barriers do require fire dampers in fully ducted hvac systems. These fire dampers are designed for use in duct systems or penetrations of fire rated barriers that have been designed to have pressurized airflow when the dampers are expected to cycle closed during fires. Static fire dampers are used in applications where the fans shut down during fire and smoke control.

Lloyd industries has been an active manufacturer of access doors fire and smoke dampers and h v a c. Since the development of modern fire damper protection equipment lloyd industries inc. When a rise in temperature occurs the fire damper closes usually activated by a thermal element which melts at temperatures higher than ambient but low enough to in. Static fire dampers can be used in both vertical and horizontal positions.

Fire dampers are passive fire protection products used in heating ventilation and air conditioning ducts to prevent the spread of fire inside the ductwork through fire resistance rated walls and floors. Dayton square fire dampers with sleeve. Electrical wiring and piping may not be installed in an exhaust duct over a frying vat or grill. 1000 pa at the rated airflow.

If the air duct is an air transfer opening meaning it is not fully ducted at the fire rated barrier then the duct needs a fire damper where other openings are required to be protected as well. They can accommodate airflow in either direction. Fire dampers are essentially metal louvres that must be installed wherever ventilation ductwork crosses a fire resistance rated internal wall or curtain. Fire smoke dampers are similar to fire dampers in fire resistance rating and also prevent the spread of smoke inside the ducts.

Fire dampers are ul555 tested and labeled devices installed in ducts and air transfer openings or air distribution systems designed to close upon the detection of heat. As of april 1 1992 all fire dampers used in hvac systems that might not cycle the blower off during a building fire must be listed and labeled for dynamic closure by underwriter laboratories. Fusible link melts releasing the fire damper curtain. Dynamic duct fire dampers.

Metal fab s dynamically rated fire dampers are tested and approved for use up to 4 w c. Heavy duty coil spring drives the fire damper curtain closed. Static duct fire dampers. Normally they stay open to allow airflow but in the event of fire they shut automatically to compartmentalise the building buying valuable time to evacuate the building.

However metal piping and electrical wiring installed in a metal protective enclosure may be installed within ventilation ducts provided that the piping or the wiring does not interfere with the operation of fire dampers. In diagram figure 14 i note ii reference is made to actuation using a fusible link operating at 74 c also clause 6 83.