The Ministry of Road Transport & Highways (MoRTH) has issued a Draft Notification on 21st September 2021 for introducing the Fire Alarm System and Fire Protection System in the Passenger (or Occupant) Compartment in buses, through an amendment in AIS (Automotive Industry Standard)-135.
The draft notification is intended for fire detection and protection in the passenger compartment for Type III buses and School Buses. Type III buses are those designed and constructed for long distance seated passenger transport. Studies on fire incidents indicate that injuries to passengers are mainly due to heat and smoke in the passenger compartment. These injuries can be prevented if the heat and smoke in the passenger compartment is controlled by providing an additional evacuation time (of at least 3 minutes) to the occupants by thermal management during fire incidents.
A technical solution to this problem has been developed by the Ministry in consultation with various stakeholders, including DRDO (Defence Research Development Organisation). A water mist-based active fire protection system has been designed and developed along with a fire alarm system. Simulation studies have demonstrated that the designed system is able to manage the temperature in the passenger compartment within 50 degree C centigrade in less than 30 seconds of mist operation.
Presently fire detection, alarm and suppression systems are notified for fires originating from the engine compartment. Provisions regarding protection of occupants involve providing additional evacuation time to the occupants. Quantity of water in the bus ranges from 55 litres to 210 litres depending on seating capacity (20 to 80 people). Number of sprinkler nozzles vary from 9 to 35 depending on the size of the bus. The Ministry of Road Transport & Highways has sought comments from stakeholders on this notification.