The four specifications that decide whether the show passes review

Why fire and water are not one system

A water fountain and a flame effect are governed by different engineering rules, different failure modes, and in most jurisdictions different authorities.

The two systems must be electrically and physically separable. That means independent emergency stops, independent gas detection, and — critically — a documented shutdown sequence in which the flame circuit closes first and the water circuit continues to run, so residual heat is dissipated and the burners are cooled by the jets rather than left dry.

The design rule we apply on every project: water is the safety system for the fire, not the other way round. If the water pump stops, the flames must stop within one second, automatically, without an operator decision.

The four specifications that decide whether the show passes review

1. Separation distance, measured from the flame, not the nozzle

Approving authorities care about the thermal envelope, not the fixture. Specify the maximum flame height under worst-case wind (typically 0.5 m/s crosswind for outdoor sites), then add the radiant heat distance required by the local fire code. On most projects this puts the nearest combustible material — including tree canopies, tensile fabric, signage and the audience barrier — 8 to 15 metres from the burner axis.

Audience barriers deserve the careful reading. A barrier placed at the edge of the splash zone is not necessarily outside the radiant heat zone. Both envelopes need to be drawn on the same plan.

2. Gas supply sized for peak simultaneous ignition

A common specification error: the gas line is sized for the average flame, not the peak. When 24 burners ignite together at the climax of a show, line pressure drops, some burners light late, and the effect looks ragged. Size the manifold for 100% simultaneous ignition with a 20% margin, and specify a buffer volume or a pressure-boosting stage if the site's supply is marginal.

3. Flame detection with a hard interlock

Every burner group needs flame supervision — ionisation or UV detection — wired to a hard interlock, not a software flag. If the detector loses the flame, the gas valve for that group must close mechanically. Software can log the event; software should not be the only thing standing between a flame-out and an unburned gas release.

4. Wind monitoring tied to show presets

Above a defined wind speed, flame height must be reduced or the effect disabled. This is not a manual judgement call made by a venue operator at 19:55. Specify an anemometer feeding the show controller so the system automatically switches to a reduced-flame preset, and log every switch for the fire authority's review.

Interaction between flame and water: three details that get missed

Atomised water near burners. Cooling mist is great for the audience and terrible for ignition. If mist nozzles are placed within the burner plenum's air intake zone, the igniter will struggle and flame supervision may trip. Keep mist 3 metres clear of any burner intake.

Laminar jets crossing the flame zone. Jumping laminar arcs that pass in front of a burner create a refractive shimmer that reads beautifully on camera — and also splash onto hot components. Specify a stainless deflector or accept a reduced flame height wherever the two effects overlap.

Water-borne debris. Outdoor basins collect leaves. A blocked burner cooling line becomes a hot spot. Include strainers on every burner cooling circuit and put their cleaning interval in the maintenance manual, not in a footnote.

Control architecture: one clock, two subsystems

The show controller should treat the flame system as a slave device with a limited command set: ignite group, set flame height, extinguish group. It should never be able to command a gas valve directly. The recommended layering:

1. Show controller — timecode, music, water and light cues, flame height requests.

1. Flame management unit — validates each request against wind speed, water flow confirmation, and interlock status; issues or refuses ignition.

1. Burner control module — pilot, main valve, flame supervision, per group.

1. Hard safety chain — E-stop, gas detection, water-flow switch, fire alarm interface, all wired to close the main gas solenoid regardless of controller state.

Water flow confirmation belongs at layer four, not in software. The most reliable arrangement ties a flow switch or pressure switch on the fire-effect cooling circuit directly into the gas solenoid circuit, so a pump trip closes the gas valve before any processor is aware of the problem.

When fire is the wrong answer

Not every site should have flames. Exclude or defer the fire effect when:

• The venue is indoors with limited air change and no mechanical extract sized for combustion products.

• The nearest neighbours are within the radiant heat envelope and cannot be screened.

• The site has no qualified gas maintenance contractor within a reasonable response radius. An effect nobody can service safely is a liability, not an attraction.

• The show will run unattended. Flame effects want a trained operator or a supervised automatic sequence with remote monitoring.

In these cases, cold mist plus high-power laser, or a well-programmed water-and-light climax, delivers most of the emotional impact with none of the regulatory load. We routinely propose exactly this substitution — and clients rarely feel they lost anything on opening night.

What to put in the tender document

If you are writing the specification rather than the design, include these five lines and the bids you receive will be far easier to compare:

• Maximum flame height, with the wind speed at which it applies.

• Required separation distances, with the drawing that proves them.

• Gas type, supply pressure, and peak simultaneous ignition demand.

• The shutdown sequence, written as a numbered list with timings.

• The name and registration of the gas safety inspector who will sign off.

Building it with WJ Fountain

WJ Fountain manufactures fire and water performance fountains — including outdoor fountains with fire, water dancing fountain shows with fire and customised fire fountains — as a combined system with a single control architecture and a documented safety chain. Our engineering team has delivered water-and-fire shows across four continents, and we will tell you at concept stage if your site should not have flames.

Most projects move from signed drawing to installed show within 60 working days. Send us your site plan and the effect you have in mind, and we will return a specification you can take to your fire authority.

About WJ Fountain Wuxi Wenjin Fountain Engineering Co., Ltd (WJ Fountain) is a China-based music fountain manufacturer and water-feature engineering company founded in 1999. With a 50,000 m² plant, 500+ staff and 30+ years of core expertise, WJ Fountain designs, builds and installs music fountains, fire and water shows, water screen shows, dry floor fountains and digital water curtains worldwide, typically within 60 working days, shipping FOB via the Port of Shanghai.

Media Contact WJ Fountain (Wuxi Wenjin Fountain Engineering Co., Ltd) Address: No. 3, Nanxin East Road, Heqiao Town, Wuxi, Jiangsu, China Tel / WhatsApp: +86 13812078746 | Email: shen_zhw@163.com Website: www.wjfountain.com