Facility Management (FM) is a strategic discipline that combines maintenance, engineering, energy management, financial control, safety, service quality, and customer satisfaction. For a complex facility such as a hospital, the dashboard must also measure clinical-service continuity, critical utility reliability, and patient safety. The objective is to move from simply reporting completed work orders to measuring whether the facility is safe, reliable, efficient, and delivering value. 1. What is a Facility Management Master Dashboard? A Facility Management Master Dashboard is a centralized reporting system that consolidates operational data from the Computerized Maintenance Management System (CMMS), Building Management System (BMS), energy meters, finance records, safety inspections, and customer feedback. 12 It allows senior management, facility managers, maintenance managers, and engineering teams to answer questions such as: Are critical assets available when required? Are prev...
Fire Pump Types & Starting Pressure Sequence — Practical Fire Protection Engineering Guide
Fire pumps are critical components of a building's fire protection system. They provide the required water flow and pressure to sprinkler systems, hydrants, standpipes and other approved firefighting systems when the available water supply cannot meet demand.
In hospitals, hotels, high-rise buildings and industrial facilities, correct pump selection, pressure settings, controller configuration and routine testing are essential for reliable fire protection.
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1. Main types of fire pumps
1. Electric main fire pump
The primary firefighting pump in an electrically driven arrangement. Its controller starts the pump automatically when system pressure falls to the configured start pressure.
Key points: Reliable power supply, approved controller, correct motor protection and starting arrangement, and compliance with the applicable fire-pump standard.
2. Diesel-engine-driven fire pump
Provides an alternative drive source where included in the approved design. It requires a suitable diesel engine, fuel supply, starting batteries, cooling, exhaust and ventilation.
Key point: It may be configured to start at a lower pressure than the electric pump, but the actual sequence must follow the approved design and applicable requirements.
3. Jockey pump
A small pressure-maintenance pump that compensates for minor leakage and small pressure fluctuations. It reduces unnecessary starts of the main fire pump.
Key point: It is not designed to supply the full firefighting demand and cannot replace the main fire pump.
4. Water transfer pump
Transfers water between tanks or supply arrangements where required by the system design. A transfer pump does not automatically qualify as a listed fire pump or replace the required fire-pump installation.
2. Which pump starts first when pressure drops?
A typical arrangement uses pressure-based automatic starting. The exact sequence depends on the approved design, controller configuration and applicable code.
Normal condition
System pressure is maintained within its normal operating range.
Stage 1 — Jockey pump
Starts after a small pressure drop to restore system pressure.
Stage 2 — Main electric fire pump
Starts automatically when pressure falls to its configured start set point.
Stage 3 — Diesel fire pump, if provided
Starts at its configured set point if pressure continues to fall, including when the electric pump has failed or cannot meet demand.
Important engineering clarification: The diesel pump does not necessarily wait for an electrical failure signal. In a typical pressure-start arrangement, it responds to its own configured pressure set point. Therefore, it may start while the electric pump is running if system pressure falls sufficiently.
Fire pumps are generally expected to continue operating after automatic starting until they are stopped in accordance with the approved controller arrangement and applicable requirements. Do not assume they will automatically stop when pressure recovers.
3. Understanding fire pump pressure settings
There is no single starting pressure suitable for every building. Set points must be calculated from the system's hydraulic design and pump characteristics.
The following terms are important:
Jockey pump cut-in pressure: Pressure at which the jockey pump starts.
Jockey pump cut-out pressure: Pressure at which the jockey pump stops.
Main fire pump start pressure: Pressure at which the main fire pump controller initiates automatic starting.
Standby fire pump start pressure: Pressure at which the standby pump initiates starting, if the design uses pressure-based sequencing.
Churn pressure: Pump discharge pressure at zero flow, under the specified operating conditions.
Rated pressure: Pressure rise specified at the pump's rated flow and speed.
System design pressure: Pressure the system and its components are designed to accommodate, considering static head, pump pressure and other relevant conditions.
Illustrative pressure sequence
The following values are hypothetical and are not recommended set points for an actual installation.
|
Equipment |
Example start pressure |
Example stop behavior |
|
Jockey pump |
8.0 bar |
Stops at its configured higher pressure |
|
Main electric pump |
7.0 bar |
Normally requires an authorized stop procedure |
|
Diesel standby pump |
6.0 bar |
Normally requires an authorized stop procedure |
This example demonstrates the sequence only. Actual settings must account for water-supply pressure, pump churn pressure, elevation, hydraulic demand, component pressure ratings and applicable NFPA 20 requirements.
4. How to calculate the required pressure
For an initial engineering assessment, the static pressure required to overcome elevation can be estimated using:
\[
P=\rho g h
\]
For water, a useful approximation is:
\[
\Delta P \approx 0.0981h \text{ bar}
\]
where \(h\) is elevation in metres.
For example, a vertical rise of 30 m creates approximately:
\[
\Delta P=0.0981\times30=2.94\text{ bar}
\]
This is only the static elevation component. The actual fire-pump design must also consider the required residual pressure at the hydraulically remote outlet, friction losses, fittings, backflow devices, system configuration and available water-supply pressure.
Do not size or set a fire pump using elevation alone. Hydraulic calculations and the approved pump curve are essential.
5. Main fire pump commissioning checklist
Commissioning checklist
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Testing must be performed by competent personnel using an approved procedure. Do not create a real fire-system pressure drop or start pumps without authorization, because testing can affect the building's fire protection and water supply.
6. Common operational problems
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7. Applicable standards and final recommendation
The principal reference is NFPA 20 — Standard for the Installation of Stationary Pumps for Fire Protection, using the edition adopted by the authority having jurisdiction. Related standards may include NFPA 25 for inspection, testing and maintenance of water-based fire protection systems, plus local Civil Defence and building requirements.
For facility managers and MEP engineers, remember these five points:
The jockey pump normally responds to small pressure losses first.
The main fire pump starts at its approved pressure set point.
A standby diesel pump may start at a lower set point if pressure continues to fall.
Pressure settings must be coordinated with pump curves, hydraulic calculations and equipment pressure ratings.
Verify the actual sequence during commissioning and document the results.
Never copy fire pump pressure settings from another building without checking the approved hydraulic design and controller requirements.
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