Startup Delay for F300 Jet Fans

According to BS 7346‑7 standards and the Iranian Fire Department regulations, upon transition from normal to fire mode, the following sequential activation must occur after a suitable time delay:

• Main exhaust fans (F300 parking exhaust fans) shall be started first,
• Followed by the main supply (make‑up air) fans,
• Finally, the required number of ceiling‑mounted jet fans shall be activated to effectively direct smoke toward the exhaust points.

The duration of this delay must be calculated based on the design of occupant escape routes.

The delay time for F300 jet fan startup depends on the following factors and must be approved by the relevant legal authority:

• Dimensions and geometry of the parking facility
• Number and location of exhaust fans and jet fans
• Number and type of occupants present in the facility
• Number and location of suitable exits

When positioning the main exhaust points, careful attention must be given to the location of exits and escape routes. The layout must be designed to ensure that exits and evacuation paths are not compromised or put at risk.