An inventory of combustible materials and potential ignition sources during the construction phase and for the completed end station has been made. The fire protection system is designed to mitigate the fire hazards associated with the identified materials and equipment. Emphasis is to reduce the combustible material inventory, provide early detection and to suppress a fire with state of the art fire systems.
In the shield houses, clean agent suppression system (figure 2.1.4.4) has been installed to obviate collateral damage to the detectors and associated electrical and electronic equipment.
Hall A has installed standard ionization detector in the ceiling of the detector huts and ionization smoke detectors in each equipment rack in the shield house; such detectors cause a shunt trip to turn off power to a given rack when smoke is detected in that rack.
Explosive gas sensors are installed on the HRS detectors to monitor the integrity of the drift chambers in each shield house. Eventually, the target assembly will include a liquid hydrogen target; explosive gas sensors will be installed on and/or around the target.
The main VESDA panel can be found in the room behind the door at the bottom of the truck ramp on the right hand side as you walk out of Hall A. This panel will indicate where in the Hall the VESDA detected a problem. A VESDA alarm indicates the possibility of a fire and hence EXTREME caution should be employed in such an event. It is worth noting that all the permanent Hall A staff members have received TJNAF's fire safety training.
All the detectors in the HRS huts are powered by clean power. The hut clean power is interlocked to the VESDA system. If the VESDA system senses smoke, it trips all the clean power in the hut. The sensitivity of the VESDA head is 0.003% to 0.3%.
There is a map indicating the evacuation routes of the end station complex posted outside the Hall A counting house.
All experimental personnel are appropriately trained to respond to a fire situation.
The gas shed, located outside the Hall A truck access is a building 24 10 10 feet. It is divided into three areas. Electronics 8 10, warm storage 8 10, and outside storage 8 10. In the event that a fire or smoke is detected in this building the gas system is shut down. The building complies with the TJNAF flammable gas code. The building has been fitted with sprinklers, although current regulations do not permit this system to be activated.