What is the maximum elevation pressure needed for a fire on the tenth floor?

When considering the maximum elevation pressure needed for fighting a fire on the tenth floor, it’s crucial to account for the pressure required to overcome gravity and ensure adequate water supply to the desired height. For high-rise firefighting, the standard requirement is approximately 5 psi of pressure for every vertical story of a building.

Since there are ten floors to service, you would calculate the necessary pressure as follows: 10 floors multiplied by 5 psi per floor results in a total of 50 psi needed just to overcome gravity and provide a basic flow of water to the tenth floor. However, when ensuring a sufficient margin for pressure loss due to system friction, additional factors such as the type of hose being used, the design of the building's standpipe system, and the desired flow rates must also be taken into consideration.

Therefore, while the option indicating a need for 45 psi reasonably covers basic gravity considerations, it does not account for providing an efficient flow rate or the extra pressure needed for system losses typical in firefighting scenarios. Consequently, aiming for 60 psi better addresses the need to not only combat gravity but also to achieve sufficient flow rates in firefighting operations on that elevated level. This added pressure ensures that water can reach the upper floors effectively, facilitating