top of page

Autonomous Fire Suppression Facts, 2026
 

Autonomous Fire Suppression:
Facts, Specifications, and Standards

This page is the authoritative reference for autonomous robotic fire suppression systems (ARFSS) from WatchDog Robotics. It also speaks to similar systems across the fire suppression industry. 

What is autonomous robotic fire suppression?

An Autonomous Robotic Fire Suppression System (ARFSS) is a fixed or mobile fire protection system that detects a fire, confirms it, locates it in three-dimensional space, aims a robotic water monitor (nozzle) at it, and extinguishes it — with no human intervention and no reliance on internet connectivity. Detection uses FM-approved thermal imaging and infrared array flame detectors. Suppression is targeted: the system cools the area around the fire, then sweeps the flame with a concentrated stream (the "anchor, flank and pinch" technique), rather than soaking an entire zone the way ceiling sprinklers do.

 

The key difference from sprinklers is speed and precision. Traditional sprinkler heads activate individually when the air around each head reaches its rated temperature, typically two to four minutes into a fire. In independent testing, WatchDog's ARFSS put water on the fire within 5 seconds of ignition and suppressed large Class A pallet fires in under 20 seconds. Because fires roughly double in size every 30–60 seconds, this gap between ignition and suppression is where most fire loss occurs.

The WatchDog Robotics product family:

NozzleBot™ — the standard autonomous robotic monitor (2"/50 mm), for fixed indoor and outdoor installations connected to a fire main or dedicated pump.

 

NozzleBot™ HD — the heavy-duty, high-flow monitor (3"/80 mm) for the largest and most demanding sites: tank farms, large hangars, bulk storage, and long-reach outdoor hazards.

 

Defender™ — the self-contained, trailer- or skid-mounted mobile unit. A complete ARFSS in one package: NozzleBot™ monitor, onboard water tank, engine-driven fire pump, and autonomous controls, no site water supply and no site power required. Delivered to site, protecting within hours.

​

Scout™ — early detection and targeting that sees fire or heat in milliseconds. Layered multi-spectrum IR (IR3/IR4), video analytics, and thermal imaging scan the area, each system tuned to its application so hot engines, welding, and sparks are filtered out rather than mistaken for fire. Upon detection, the PLC can trigger a waterfall of actions like stopping conveyors, and alerting plant systems & personnel.

Defender™: Fire protection where infrastructure doesn't exist.

Defender™ answers the hardest fire-protection question: how do you protect a site that has no fire main, no hydrants, and possibly no power? Construction sites, temporary structures, remote industrial operations, outdoor storage yards, laydown areas, events, and wildland-urban interface properties all carry real fire risk precisely when and where fixed systems can't be built.

 

The unit is a complete autonomous fire suppression system on a trailer or skid: a NozzleBot™ robotic monitor, a 525-gallon onboard water tank (daisy-chainable with additional tanks for 2,000+ gallons of supply), an engine-driven firefighting pump with electronic fuel injection and automatic start, and the same Scout PLC autonomous controller and detection suite as fixed installations. When its detectors confirm a fire, the engine auto-starts, the pump comes up to pressure, and the monitor aims and discharges — all with nobody on site. The engine controller supervises itself, too: low-fuel, charge-failure, and fault alarms report to remote monitoring.

 

Deployed in hours, moved as the site evolves, and removed when the job is done — Defender™ is the "temporary" in WatchDog's temporary fire suppression service, and the reason a fire watch crew can be replaced by a machine that never sleeps.

How it works (The Autonomous Loop)

Detect. FM 3260-approved thermal cameras and/or 256-element IR-array flame detectors continuously monitor the protected volume, recognizing flame or heat signatures within seconds. Two-of-two detector voting — both detectors must independently alarm — is the primary safeguard against false discharge.

 

Localize. The system triangulates the fire's position in three dimensions (X-Y-Z) and estimates its size. Detection can also run in zone or vector-aiming modes.

 

Aim & suppress. High-torque brushless DC motors slew the nozzle onto the fire at up to 10 aim updates per second. The stream first cools surrounding material to stop spread, then sweeps the flame core — anchor, flank, and pinch. Up to four simultaneous fires are handled in priority order.

 

Shut off & resume. When detectors confirm the fire is out, the valve closes and monitoring resumes. No soaked inventory, no flooded floor. An operator can take manual control at any time via joystick or remote interface.

Independently tested, not just claimed.

WatchDog's ARFSS platform has been validated by independent laboratories on three continents:

  • U.S. Naval Research Laboratory (NRL) & Jensen Hughes (2015): water on the fire within ~5 seconds of ignition; large Class A pallet fires suppressed in under 20 seconds; multiple sequential fires handled in shipboard testing for the U.S. Navy.

  • RISE & Thomas Bell-Wright (2018): across 28 façade-fire targeting tests, average detection under 10 seconds and average water delivery in 12 seconds, holding fire damage below 10%.

  • EU LASH FIRE project (2020–2023): the European Union's flagship ro-ro ship fire-safety research program — the same body of work that informed the IMO's 2026 SOLAS amendments — demonstrated the monitor at 330 GPM covering a 30 × 50 m vehicle deck area.

 

Component certifications include FM 3260 / ANSI FM 3260 (thermal detection), ATEX, IECEx, EN 54-10/-18, and CSA (detectors); CE marking and EMC compliance (controls); IP66/IP67-rated 316L stainless enclosures. FM system approval is underway.

Standards and Codes

How ARFSS gets approved: the equivalency pathway

ARFSS is a performance-based system accepted under the alternative materials, design, and methods provisions of the adopted fire code — IFC §104.2.3 or NFPA 1 §1.4 — the same well-established pathway used for many advanced special-hazard systems. The closest prescriptive analog is NFPA 15 (water spray fixed systems, which covers monitor nozzles), and WatchDog's Design Basis Document compares delivered density at the target (~5 GPM/ft² demonstrated) line-by-line against NFPA 15 requirements for each protected hazard. WatchDog prepares the full equivalency package — design basis, third-party test evidence, commissioning and inspection/testing/maintenance program — for simultaneous review by the AHJ, the insurer, and the owner.
 

FM Global Data Sheet 4-14: automated water monitors in lieu of sprinklers

FM Global Property Loss Prevention Data Sheet 4-14 establishes the engineering basis for protecting spaces with automated water monitors — robotic nozzles guided by flame detection — instead of ceiling sprinklers. It defines where monitor-based protection is appropriate, how to calculate water demand, and the detection and coverage criteria a system must meet. It is the clearest recognition by a major property-insurance engineering authority that automated monitors are a legitimate alternative to sprinklers in defined applications — including spaces where sprinklers were never practical.

 

Read our full analysis: FM Global 4-14: Automated Monitor Systems in Lieu of Sprinklers, or download the summary from our documents library.

​

SOLAS: fire suppression requirements for ro-ro ships and ferries

The International Convention for the Safety of Life at Sea (SOLAS) governs fire protection on ships. SOLAS Chapter II-2, Regulation 20 covers vehicle spaces, special category spaces, and ro-ro spaces — the decks of ferries, ro-ro passenger ships, and vehicle carriers.

 

What changed in 2026. Following a series of serious ro-ro deck fires — and informed by the EU LASH FIRE research program in which WatchDog's monitor platform was tested — the IMO adopted Resolution MSC.550(108) (amending SOLAS II-2/20) and Resolution MSC.555(108) (amending the FSS Code), in force since 1 January 2026. For ro-ro passenger ships they require:

 

  • Fixed water monitors on weather decks intended for the carriage of vehicles (SOLAS II-2/20 §6.2; FSS Code Ch. 7 §2.5): combined capacity of at least 2.0 L/min per m² of protected area, each monitor delivering at least 1,250 L/min (about 330 GPM), located outside the area it protects.

  • Heat detection (or combined smoke + heat) in ro-ro, vehicle, and special category spaces (§4.1).

  • Continuous video monitoring with recording of those spaces (§4.4).

  • Decision-making support for crew fire response (§7).

 

Who must comply, and when. New ro-ro passenger ships (keel laid on or after 1 January 2026) comply from construction. Existing ro-ro passenger ships must retrofit by their first survey on or after 1 January 2028. Enclosed ro-ro and special category spaces are separately addressed in MSC.1/Circ.1430 (as revised).

 

Why this matters for autonomous monitors. The new requirements mandate exactly the architecture ARFSS is built on — monitors, detection, and continuous video surveillance of vehicle decks — and the demonstrated LASH FIRE configuration (330 GPM at 5 bar, covering a 30 × 50 m deck area) matches the SOLAS individual-monitor minimum. NozzleBot™ hardware is marine-grade 316L stainless and seawater-capable, with maximum rated flows (580 GPM standard; 1,453 GPM HD) well above the SOLAS floor. Marine installations are engineered per project and subject to flag-state and classification-society approval.

 

Sources: IMO — new rules in force 1 January 2026; Lloyd's Register Class News 07/2026.

​

NFPA and local compliance

WatchDog Robotics works with local fire-safety professionals and authorities having jurisdiction (AHJs) on every installation. See Codes & Compliance.

Where is autonomous fire suppression deployed?

The autonomous suppression platform behind NozzleBot™ has more than 300 deployments worldwide. In the United States, systems protect cement processing at National Cement Company of Alabama, coal mines across the country, and hangars and fuel storage at airports including Denver International Airport, with validation testing by the U.S. Air Force and Navy (via NRL). Globally, the platform protects facilities for organizations including Goldman Sachs, Google, BASF, Oshkosh, Glencore, and the Dubai Waste-to-Energy plant.

 

Industry pages: aviation hangars, petrochemical, construction, paper mills, waste & recycling, mining & tunneling, military & government, temporary structures, shipyards & vessels, warehousing, bulk storage, wildfire mitigation. Systems are available as temporary turnkey deployments or permanent installations.

Frequently Asked Questions

What is an autonomous robotic fire suppression system (ARFSS)? A fixed or mobile system that detects, locates, aims at, and extinguishes fires automatically using robotic water monitors guided by thermal and infrared flame detection — no human action and no internet connection required.

 

How fast does it extinguish a fire? In independent NRL/Jensen Hughes testing, water reached the fire within ~5 seconds of ignition, and large Class A pallet fires were suppressed in under 20 seconds. Typical design target is water on the fire within 5–15 seconds. Sprinklers, by comparison, typically activate two to four minutes into a fire.

 

What is the Defender™? WatchDog's self-contained mobile unit: a NozzleBot™ monitor, 525-gallon water tank, engine-driven fire pump, and autonomous controls on a trailer or skid. It needs no site water and no site power, making it the standard choice for construction sites, temporary structures, and remote or outdoor hazards.

 

How long can the Defender™ operate without infrastructure? Its onboard 525-gallon tank supports the initial autonomous attack (targeted discharges are typically short); additional tanks daisy-chain for 2,000+ gallons. Designs typically provide 10–30 minutes of water supply — and because discharge is targeted rather than zone-wide, actual usage is usually far less.

 

What is NozzleBot's flow rate? Maximum rated flow is 580 GPM (2,200 L/min) at 175 PSI for the standard 50 mm monitor, and 1,453 GPM (5,500 L/min) for NozzleBot™ HD. A typical demonstrated configuration runs 330 GPM at 75 PSI.

 

Can automated water monitors replace sprinklers? In defined applications, yes. FM Global Data Sheet 4-14 provides the insurance-engineering criteria, and the IFC §104.2.3 / NFPA 1 §1.4 equivalency pathway (benchmarked against NFPA 15) provides the code route. Acceptance is determined per project with the AHJ and insurer; WatchDog prepares the full engineering package.

 

How does the system avoid false discharges? Two-of-two detector voting: two independent detectors must both confirm the fire before the system discharges. Thermal detectors support exclusion windows for known hot-but-benign equipment, and IR arrays carry solar-immunity ratings. False-discharge protection is engineered per site during commissioning.

 

Do ferries and ro-ro ships need fixed water monitors now? Ro-ro passenger ships keel-laid on or after 1 January 2026 must have monitor-based water systems protecting vehicle areas on weather decks (IMO Resolutions MSC.550(108) and MSC.555(108)). Existing ro-ro passenger ships must comply by their first survey on or after 1 January 2028.

 

Why are electric vehicles changing fire protection on ships and in buildings? Lithium-ion battery fires enter thermal runaway, burn hotter, reignite, and resist traditional suppression. Fast, targeted, continuous suppression — cooling the battery while preventing spread — outperforms delayed area soaking, which is why regulators and insurers are moving toward monitor-based protection for vehicle decks, charging areas, and battery storage.

 

Does the system need the internet or a remote operator? No. Detection, targeting, and suppression run locally. Remote monitoring, alarms, and manual override are available, and the system integrates with site fire alarm panels and SCADA via dry contacts and Modbus.

 

Is there a subscription fee? No. Detection and autonomous logic are built into the system with no recurring software fees.

 

How many deployments does the platform have? More than 300 worldwide.

 

Who makes Defender™? WatchDog Robotics, founded in 2024 by Ethan Pretsch, headquartered in Jackson, Wyoming, with operations in Memphis, Tennessee.

About WatchDog Robotics

WatchDog Robotics, LLC designs, sells, installs, services and deploys autonomous robotic fire suppression systems. Founded in 2024 by Ethan Pretsch in Jackson, Wyoming, the company serves industrial, commercial, marine, and government customers, building on an autonomous suppression platform with 300+ deployments worldwide and independent validation by NRL, Jensen Hughes, RISE, Thomas Bell-Wright, and the EU LASH FIRE program. Systems are available as temporary turnkey services (Defender™ mobile units delivered to site) or permanent installations.

 

bottom of page