Welcome back to another case study. This month, we are looking at the damage a fan lacking proper grease containment can do to a slanted roof. In the photos below, you will see a fan that has no hinge and no grease containment receptacle, allowing the grease from the fan to run down the roof. This violates several NFPA 96 codes, as well as regulations from the EPA (not considering local municipal regulations that may also be in effect).

Roof Deterioration

To start, take a look at these two pictures:

See how much caked on grease is spilling down the fan and onto the roof? Without even getting into the NFPA 96 and EPA violations, this is a disaster for a rooftop. Grease will quickly rot and deteriorate a rooftop, which could cost thousands to repair. The cost it would take to repair a rooftop from the destruction of grease is not worth it; purchasing an appropriate grease containment system with a hinge kit costs far less and doesn’t subject you to additional fines. Our product, Grease Away, can be used to clear this rooftop of grease. It might not keep it from having to be repaired, but just sprinkle it on the grease and let the next rainfall wash it away. It’s safe for storm drains once Grease Away has broken it down.

Grease Containment

The lack of proper grease containment on this fan violates the following NFPA 96 codes:

“ Rooftop termination shall be arranged with or provided with the following:

(4) The ability to drain grease out of any traps or low points formed in the fan or duct near the termination of the system into a collection container that is noncombustible, closed, rainproof, and structurally sound for the service to which it is applied and that will not sustain combustion.”

This fan could be equipped with either our Grease Box or Grease Gutter Sidekick. The Grease Box is perfect for commercial kitchens that need a little extra support. It has three tiers of our hydrophobic filters and is in a closed receptacle, so it is also wind and weatherproof. The Grease Gutter Sidekick is the perfect solution for normal commercial kitchens with average output, again utilizing our hydrophobic filters.


Finally, this fan needs a hinge. Our patented Super Hinge is the only NFPA 96 compliant hinge on the market. We offer different sizes to provide fans of varying lengths the proper amount of coverage. As stated earlier, hinges should span across at least 60% of the fan base to be considered safe enough for service personnel to clean. This is not an NFPA 96 requirement; the 60% is what Omni Containment Systems has found to be the best and safest length. It is also one of our requirements if you purchase a hinge from us or one of our distributors; your hinge must span 60% of the fan base in order to keep the warranty on your hinge.

Having a hinge on this fan is imperative—or any fan for that matter. It helps protect service personnel who may service the fan. It would be dangerous to have a fan this size crash down onto the roof, someone’s hand, or someone’s head. It could be deadly and costly, for all involved. Protecting human lives and your rooftop with a fan and hinge is the cheapest and safest option for your business.


Having a fan without a proper grease containment system is one thing, but to have none at all? It could cost a company more money than it’s worth. Fines from the EPA, local municipalities, and the promise of having to replace the rooftop at some point far outweighs the cost of properly hinging, cleaning, and adding a grease containment system to this unit. Omni Containment Systems wants to help make your commercial cooking operation compliant and safe. Contact us to learn more about how our products can help you.