Clean Agent Fire Suppression Systems
Corpus sync: neutrality remakes, note hygiene, datasheet relocation, transformer-split cross-refs
Showing changes from Rev 6
to Rev 7
in Clean Agent Fire Suppression Systems.
---
title: Clean Agent Fire Suppression Systems
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### The listed clean-agent system is an engineered assembly whose flow calculations, container fill ranges, pipe-length and fitting limits, and nozzle coverage are valid only when the system is designed using the manufacturer's listed design software and installed within the limits of the manufacturer's design and installation manual. {note}
+### The clean-agent system shall be designed, installed, and commissioned by personnel trained and certified by the manufacturer of the listed system being installed, in accordance with NFPA 2001.
+
```datasheet
label: Designer / Installer Qualification Basis
…7 unchanged lines
```
−### The clean-agent system shall be designed, installed, and commissioned by personnel trained and certified by the manufacturer of the listed system being installed, in accordance with NFPA 2001.
−
### The Contractor shall hold the licensing required by the state and local jurisdiction for fire suppression system work.
…42 unchanged lines
### Inert-gas agents are stored as a high-pressure gas and are likewise temperature sensitive. {note}
+### The agent storage containers and the protected enclosure shall be within the temperature range for which the listed system is rated.
+
```datasheet
label: Agent Storage Temperature Range
…18 unchanged lines
```
−### The agent storage containers and the protected enclosure shall be within the temperature range for which the listed system is rated.
−
### The minimum design temperature of the enclosure governs the agent quantity, because a colder, denser atmosphere requires more agent to reach the design concentration. {note}
…14 unchanged lines
### The two agent families differ fundamentally in how they extinguish fire, in how much agent is required, in their occupant-safety behavior, and in their discharge and venting requirements, and the choice drives the rest of the design. {note}
+### Halocarbon agents (for example HFC-227ea and the fluoroketone FK-5-1-12) extinguish primarily by absorbing heat from the flame; they are stored as a liquid, require a relatively small storage footprint, flood the space quickly, and are subject to a maximum 10-second discharge time. {note}
+
+### Inert-gas agents (for example IG-541, a blend of nitrogen, argon, and carbon dioxide; IG-55, a nitrogen-argon blend; and IG-100, nitrogen) extinguish by displacing oxygen and reducing it below the level that supports combustion; they are stored as a high-pressure gas, require a substantially larger bank of cylinders, discharge over a longer 60-second period, and demand careful pressure-relief venting because they add a large gas volume to the enclosure. {note}
+
+### The agent shall be selected for the hazard, the occupancy condition, the available storage space, the enclosure's ability to tolerate the over- and under-pressure of discharge, and the Owner's environmental objectives.
+
```datasheet
label: Agent Family
…18 unchanged lines
```
−### Halocarbon agents (for example HFC-227ea and the fluoroketone FK-5-1-12) extinguish primarily by absorbing heat from the flame; they are stored as a liquid, require a relatively small storage footprint, flood the space quickly, and are subject to a maximum 10-second discharge time. {note}
−
−### Inert-gas agents (for example IG-541, a blend of nitrogen, argon, and carbon dioxide; IG-55, a nitrogen-argon blend; and IG-100, nitrogen) extinguish by displacing oxygen and reducing it below the level that supports combustion; they are stored as a high-pressure gas, require a substantially larger bank of cylinders, discharge over a longer 60-second period, and demand careful pressure-relief venting because they add a large gas volume to the enclosure. {note}
−
−### The agent shall be selected for the hazard, the occupancy condition, the available storage space, the enclosure's ability to tolerate the over- and under-pressure of discharge, and the Owner's environmental objectives.
−
### The Contractor shall not substitute a different agent or agent family after design approval without re-running the design concentration, occupant-safety, flow, and enclosure-integrity analyses and resubmitting them, because the agents are not interchangeable.
…5 unchanged lines
### Where the protected hazard is energized electronic or electrical equipment, an additional design factor is applied per NFPA 2001 to account for the deeper-seated nature of such fires. {note}
−```datasheet
−label: Design Basis (fire type)
−type: radio
−options:
− - "Class A surface fire (electronic / records / general contents)"
− - "Class A energized-equipment hazard (added NFPA 2001 design factor)"
− - "Class B fuel (cup-burner concentration × 1.3)"
−default: "Class A energized-equipment hazard (added NFPA 2001 design factor)"
−```
+### The agent quantity shall be calculated to establish at least the minimum design concentration throughout the protected volume at the minimum enclosure design temperature, in accordance with NFPA 2001.
```datasheet
…21 unchanged lines
```
−### The agent quantity shall be calculated to establish at least the minimum design concentration throughout the protected volume at the minimum enclosure design temperature, in accordance with NFPA 2001.
−
### The design concentration and its basis shall be stated on the calculations and shall be the more demanding where multiple fire types are present.
+```datasheet
+label: Design Basis (fire type)
+type: radio
+options:
+ - "Class A surface fire (electronic / records / general contents)"
+ - "Class A energized-equipment hazard (added NFPA 2001 design factor)"
+ - "Class B fuel (cup-burner concentration × 1.3)"
+default: "Class A energized-equipment hazard (added NFPA 2001 design factor)"
+```
+
## Occupancy and the NOAEL / LOAEL Safety Margin {toc}
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### The releasing unit continuously supervises the detection, the actuation circuits, the manual release and abort stations, and the agent-container and pressure-supervisory devices; processes the detection logic; provides the pre-discharge delay and abort; and energizes the actuator that releases the agent. {note}
+### The system shall be actuated by a dedicated releasing control unit listed to UL 864 for releasing service, in accordance with NFPA 72 and NFPA 2001.
+
```datasheet
label: Releasing Control Unit Listing
…4 unchanged lines
```
−### The system shall be actuated by a dedicated releasing control unit listed to UL 864 for releasing service, in accordance with NFPA 72 and NFPA 2001.
−
### The releasing function is distinct from the building fire alarm system: the releasing unit transmits alarm, supervisory, and trouble signals to the building fire alarm system and the supervising station for occupant notification and off-premises reporting (see [[sync/fire-alarm-systems]]), but the agent release decision is made by the dedicated releasing unit. {note}
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### Cross-zoning prevents an extremely costly and disruptive accidental discharge from one faulty or transiently triggered detector while still providing fast response when a real fire is confirmed by detectors on two separate zones. {note}
+### Automatic actuation shall require two independent detection inputs in alarm before the discharge sequence begins — a cross-zoned (or counting-zone) detection arrangement — so that a single detector in alarm cannot by itself release the agent.
+
```datasheet
label: Automatic Actuation Logic
…5 unchanged lines
```
+### Detectors shall be spot-type smoke detectors listed to UL 268, or aspirating (air-sampling) detection where early-warning sensitivity is required, located and spaced per NFPA 72 with the spacing reduced as required for the air movement in the protected space.
+
```datasheet
label: Detection Type
…7 unchanged lines
```
−### Automatic actuation shall require two independent detection inputs in alarm before the discharge sequence begins — a cross-zoned (or counting-zone) detection arrangement — so that a single detector in alarm cannot by itself release the agent.
−
−### Detectors shall be spot-type smoke detectors listed to UL 268, or aspirating (air-sampling) detection where early-warning sensitivity is required, located and spaced per NFPA 72 with the spacing reduced as required for the air movement in the protected space.
−
### Where the enclosure has a raised-floor void or a ceiling plenum that is part of the protected volume, detection shall be provided in those concealed spaces as well as at the ceiling.
…2 unchanged lines
### The time delay allows occupants to evacuate and allows an abort if the alarm is investigated and found not to warrant discharge. {note}
+### On confirmation of the cross-zoned alarm, the system shall sound a distinct pre-discharge alarm, activate warning signs and strobes at the entrances to and inside the protected space, initiate the ancillary shutdowns (HVAC and fan shutdown, damper and door closure), and begin a time delay before discharge.
+
+### The time delay shall be long enough for occupant egress yet short enough that fire growth does not exceed what the design concentration can extinguish, and shall not exceed the limit established by NFPA 2001 for the occupancy.
+
```datasheet
label: Pre-Discharge Time Delay
…7 unchanged lines
```
+### A manual abort station, where provided, shall require constant manual pressure to hold the discharge in abort and shall not defeat the manual release.
+
+### Releasing the abort or operating the manual release shall allow or cause discharge.
+
+### The abort shall not silence the pre-discharge alarm and shall be of the "dead-man" type so that the system cannot be left indefinitely disabled by a jammed or taped abort.
+
+### A manual release station shall be provided at the means of egress from the protected space to allow a person to discharge the system immediately, overriding the time delay.
+
```datasheet
label: Manual Stations Provided
…6 unchanged lines
```
−### On confirmation of the cross-zoned alarm, the system shall sound a distinct pre-discharge alarm, activate warning signs and strobes at the entrances to and inside the protected space, initiate the ancillary shutdowns (HVAC and fan shutdown, damper and door closure), and begin a time delay before discharge.
−
−### The time delay shall be long enough for occupant egress yet short enough that fire growth does not exceed what the design concentration can extinguish, and shall not exceed the limit established by NFPA 2001 for the occupancy.
−
−### A manual abort station, where provided, shall require constant manual pressure to hold the discharge in abort and shall not defeat the manual release.
−
−### Releasing the abort or operating the manual release shall allow or cause discharge.
−
−### The abort shall not silence the pre-discharge alarm and shall be of the "dead-man" type so that the system cannot be left indefinitely disabled by a jammed or taped abort.
−
−### A manual release station shall be provided at the means of egress from the protected space to allow a person to discharge the system immediately, overriding the time delay.
−
## Ancillary Functions and Interlocks {toc}
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### Halocarbon containers store the agent as a superpressurized liquid; inert-gas containers store the agent as a high-pressure gas, typically in a multi-cylinder bank with a manifold. {note}
+### The container arrangement for the clean agent system shall be specified, consistent with whether the agent is a halocarbon liquid or an inert gas high-pressure bank.
+
```datasheet
label: Container Arrangement
…32 unchanged lines
### The pipe network is part of the listed system and the flow calculation governs whether each nozzle delivers its share of agent within the discharge time. {note}
+### Discharge piping shall be the type and schedule required by the listed system and by NFPA 2001, sized and arranged exactly as the manufacturer's flow calculation requires.
+
```datasheet
label: Discharge Piping
…7 unchanged lines
```
+### The pipe network shall not deviate from the calculated layout in length, size, fitting count, or tee orientation.
+
```datasheet
label: Piping Layout
…5 unchanged lines
```
−### Discharge piping shall be the type and schedule required by the listed system and by NFPA 2001, sized and arranged exactly as the manufacturer's flow calculation requires.
−
−### The pipe network shall not deviate from the calculated layout in length, size, fitting count, or tee orientation.
−
### Piping shall be reamed and blown clear of cuttings and debris before assembly.
…34 unchanged lines
### The discharge time is fixed by the agent family and is a pass/fail requirement of NFPA 2001. {note}
+### For halocarbon agents the system shall deliver at least 95 percent of the minimum design concentration within 10 seconds, because a halocarbon agent must reach concentration quickly to absorb heat before the fire grows and before agent decomposition products (such as hydrogen fluoride) accumulate.
+
```datasheet
label: Maximum Discharge Time — Halocarbon
…7 unchanged lines
```
+### For inert-gas agents the discharge time is longer — typically not more than 60 seconds to reach the design concentration — because the agent extinguishes by oxygen displacement and a slower fill limits the over-pressure imposed on the enclosure as a large volume of gas is added.
+
```datasheet
label: Maximum Discharge Time — Inert Gas
…7 unchanged lines
```
−### For halocarbon agents the system shall deliver at least 95 percent of the minimum design concentration within 10 seconds, because a halocarbon agent must reach concentration quickly to absorb heat before the fire grows and before agent decomposition products (such as hydrogen fluoride) accumulate.
−
−### For inert-gas agents the discharge time is longer — typically not more than 60 seconds to reach the design concentration — because the agent extinguishes by oxygen displacement and a slower fill limits the over-pressure imposed on the enclosure as a large volume of gas is added.
−
### The flow calculation shall demonstrate compliance with the discharge time for the agent family.
…4 unchanged lines
### Establishing the concentration is not enough; the fire is extinguished and hot surfaces cool over the hold period, and if the agent leaks away too quickly through unsealed penetrations, door undercuts, dampers that did not close, or a porous boundary, the fire can re-ignite. {note}
+### The enclosure shall retain the agent at or above the concentration needed to prevent re-ignition for a minimum hold (soak) time after discharge, in accordance with NFPA 2001.
+
```datasheet
label: Minimum Agent Hold (Soak) Time
…8 unchanged lines
```
−### The enclosure shall retain the agent at or above the concentration needed to prevent re-ignition for a minimum hold (soak) time after discharge, in accordance with NFPA 2001.
−
### The required hold time is commonly 10 minutes unless a different value is justified by the time the hazard will go unattended after discharge.
…5 unchanged lines
### This test substitutes for an actual agent discharge — it is impractical and wasteful to verify hold time by discharging agent — and it locates leakage paths so they can be sealed. {note}
+### The enclosure integrity shall be verified by a door-fan (enclosure-integrity) test performed in accordance with the procedure in NFPA 2001, both as a design tool and at acceptance.
+
```datasheet
label: Enclosure-Integrity Verification
…4 unchanged lines
```
−### The enclosure integrity shall be verified by a door-fan (enclosure-integrity) test performed in accordance with the procedure in NFPA 2001, both as a design tool and at acceptance.
−
### The system shall not be accepted until the door-fan test demonstrates that the enclosure will hold the agent for at least the required hold time.
…5 unchanged lines
## A modern, tightly sealed enclosure — exactly the kind that holds the agent well — cannot relieve this pressure through incidental leakage and can have its walls, ceiling, or floor structurally over-stressed unless a pressure-relief vent is provided. {note}
+## The protected enclosure shall be provided with pressure relief sized for the agent and the discharge so that the enclosure structure is not damaged by the pressure transient of discharge, in accordance with NFPA 2001.
+
```datasheet
label: Pressure Relief Provided
…5 unchanged lines
```
−```datasheet
−label: Pressure Relief Vent Type
−type: select
−drawing_ref: true
−options:
− - "Barometric (self-closing) relief damper"
− - "Motorized relief damper interlocked to discharge"
−default: "Barometric (self-closing) relief damper"
−```
+## The relief vent shall be sized from the agent quantity and discharge rate and the enclosure's allowable pressure.
```datasheet
…9 unchanged lines
```
−## The protected enclosure shall be provided with pressure relief sized for the agent and the discharge so that the enclosure structure is not damaged by the pressure transient of discharge, in accordance with NFPA 2001.
−
−## The relief vent shall be sized from the agent quantity and discharge rate and the enclosure's allowable pressure.
−
## The relief vent shall be a listed barometric or motorized damper-type relief that opens during discharge and otherwise stays closed so it does not itself become a leakage path that shortens the hold time.
+```datasheet
+label: Pressure Relief Vent Type
+type: select
+drawing_ref: true
+options:
+ - "Barometric (self-closing) relief damper"
+ - "Motorized relief damper interlocked to discharge"
+default: "Barometric (self-closing) relief damper"
+```
+
# Testing and Commissioning {toc}
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# Installation {toc}
−## General {toc}
+## The Contractor shall install the system in accordance with this standard, the approved working drawings, NFPA 2001, NFPA 72, NFPA 70, and the listed-system manufacturer's design and installation manual.
−### The Contractor shall install the system in accordance with this standard, the approved working drawings, NFPA 2001, NFPA 72, NFPA 70, and the listed-system manufacturer's design and installation manual.
+## Where these conflict, the more stringent governs, and no installation shall deviate from the conditions of the listing.
−### Where these conflict, the more stringent governs, and no installation shall deviate from the conditions of the listing.
+## Piping shall be installed to the calculated layout, reamed and cleaned, pressure-tight, and supported to resist discharge reaction forces.
−### Piping shall be installed to the calculated layout, reamed and cleaned, pressure-tight, and supported to resist discharge reaction forces.
+## Nozzles shall be installed at the locations and orientations shown.
−### Nozzles shall be installed at the locations and orientations shown.
+## Detection, manual stations, alarms, and signs shall be installed at the heights and locations required for visibility and reach.
−### Detection, manual stations, alarms, and signs shall be installed at the heights and locations required for visibility and reach.
−
## Signage {toc}
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## The Owner shall be advised of the agent recharge source and the container hydrostatic-retest schedule so the system is maintained ready throughout its life.