1. Water Tank Capacity

Fire Flow Requirements

Determine the minimum fire flow required for the facility based on local building codes and fire department requirements. This is typically expressed in gallons per minute (GPM) or liters per second (L/s) and is influenced by the type of occupancy and potential fire hazards.

Duration of Water Supply

Assess the required duration for which the fire protection system must supply water. This often ranges from 30 minutes to 2 hours, depending on the occupancy type and associated fire risk.

Type of Occupancy

Consider the type of occupancy (e.g., industrial, commercial, residential) and the associated fire risks. Different occupancies have varying fire protection needs, influencing water tank capacity.

Sprinkler System Demand

For buildings equipped with sprinkler systems, calculate the water demand for both the sprinkler system and any additional standpipe requirements.

Fire Department Connection

Ensure that the water tank capacity can support the fire department’s connection requirements, allowing for quick and efficient water supply during emergencies.

Retrofitting and Expansion

Consider future expansion or modifications to the facility that may increase water supply demands. Designing for potential growth can save costs in the long run.

System Redundancy

Evaluate the need for redundancy in the water supply system, especially for critical facilities. This may include additional tanks or backup water sources.

2. Fire Pump Selection

Pump Type

Choose the appropriate type of fire pump based on the system’s requirements:

• Electric Fire Pumps: Commonly used for permanent installations.
• Diesel Fire Pumps: Preferred for areas with unreliable power supply or for large-capacity systems.

Flow Rate and Pressure Requirements

Calculate the required flow rate (in GPM or L/s) and pressure (in psi or bar) needed to meet fire suppression needs. This involves assessing system demands, including hose lines, sprinklers, and standpipes.

Pump Sizing

Properly size the pump to meet the calculated flow and pressure requirements while allowing for a margin to accommodate pressure losses in piping and fittings.

System Configuration

Consider the layout of the fire protection system, including the distance from the water source to the highest outlet point. Ensure the pump can provide adequate pressure at all points.

NPSH (Net Positive Suction Head)

Evaluate the NPSH required for the fire pump to operate efficiently. Ensure that the water supply system can provide adequate NPSH to avoid cavitation, which can damage the pump.

Compliance with Standards

Ensure that the selected fire pump meets relevant standards and codes, such as those from the National Fire Protection Association (NFPA) and local regulations, which dictate performance and testing criteria.

Maintenance and Accessibility

Consider ease of maintenance and accessibility for service personnel. Fire pumps should be easily accessible for routine inspections, maintenance, and repairs.

Monitoring and Control Systems

Implement monitoring and control systems to track pump performance, alarms, and status indicators. This can enhance system reliability and ensure prompt response to potential issues.