FAQ: EXHAUST EXTENSIONS

Do you sell exhaust fans or smoke ejectors?

No! We only sell fans for positive pressure ventilation. Using a smoke ejector to ventilate a structure is like using a wagon to drive across the country. Please click here for why we advocate positive pressure over negative pressure ventilation.

Do you sell exhaust extensions?

No! We feel very strongly that exhaust extensions / exhaust-diversion accessories are hazardous and ineffective. They are an attempt to solve a problem that should not exist with your fan to begin with!

• If you use a gas-powered VENTRY Fan, you should not need any exhaust extensions!
• If your fan pushes enough air (thereby diluting the exhaust), it does not need an exhaust extension!
• Exhaust extensions can cause tripping and burning hazards!
• Exhaust extensions are used to FIX PROBLEMS caused by inefficient propellers and other design deficiencies. We build VENTRY Fans with Smoke-Busting Propellers that push lots of air, dilute the exhaust, and avoid the CO problem in the first place!

We have done experiments with exhaust extenders and confirmed our suspicions that they do not work reliably and are unsafe. Extensions pull the exhaust away from the fan, but our fans pull it right back in! Note, they push a lot of air and therefore PULL in a lot of air for the supply too, so nothing is gained except scene clutter and burn/trip hazards.

(A false sense of security is also dangerous; a department without a CO monitor could easily and erroneously trust that the exhaust extension is lowering CO when it really was not!)

Exhaust extensions qualify as muffler modifications, which are not approved by Honda and may void your engine warranty. Extensions can also damage engine valves and the gasket between the head and muffler. That Honda does not offer any such accessory with their engines is very telling.

On safety, we point out numerous incidents of people being burned, as exhaust extensions get very hot and can even cause fires. We were told of an exhaust extension that burned a fire hose in two, before it was charged, rending it useless while the crew was in the structure!

We emphasize that VENTRY Fans push a lot of air and produce low CO (chart), so exhaust extensions are simply not necessary. Ultimately, we are dedicated to making only the very best equipment possible and exhaust extensions greatly conflict with this goal. We encourage you to buy a fan that works so well and so efficiently that you do not need workarounds like dangerous exhaust extensions!

Note: During mop-up / overhaul, if you want to get rid of any remnant exhaust smells inside a structure, just turn the VENTRY Fan around in the doorway and use negative pressure. It will suck the air out of the structure, blow it outside, and pull 100% fresh air into the structure. You can also use Electric Fans which completely eliminate any carbon monoxide issues arising from the fan use.

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