For the past few years now, the regulatory / pretreatment community has been much more vocal and somewhat harmonious in their cries for better information, knowledge and understanding when it comes to grease interceptors. I'm right in the middle of helping a jurisdiction update their ordinance and crafting a new fats, oils grease (FOG) discharge policy and one thing that really stands out is all of the mis-information out there from manufacturers.
For decades the industry has been saturated with what we call "traditional" HGIs; known for being made of steel and being tested to the minimum requirements of applicable standards for efficiency and grease storage capacity. They are generally too small, hold too little grease, and are not maintained often enough. These older types are guaranteed to fail due to corrosion and jurisdictions are well advised to stop approving them.
Fortunately, over time there have been new innovations and noteworthy improvements with grease interceptors. Today there are options for interceptors made from thermoplastics or fiberglass, which are inert to corrosion from decaying FOG and food debris. Many of the new HGI technologies are also more efficient and hold substantially more grease than traditional types. In some circles these devices are being called "hybrid" HGIs or "high-capacity" HGIs. Jurisdictions are well advised to seek ways of approving these devices for their own benefit but also for the benefit of their constituent restaurant owners. These devices provide a win-win in my opinion.
The problem I am seeing though, is misleading information being promulgated by some manufacturers of HGIs introduced in recent years to compete in this new category of high-capacity HGIs. Instead of leading with test reports and performance data that would prove the equivalency or superiority of their performance, these other manufacturers have opted to hide behind terms like "greasy sludge capacity" or "grease design capacity". These terms have no actual meaning and they are certainly not defined terms that are industry accepted. They amount to nothing more than a manufacturer's unsubstantiated claim about the performance of their device(s).
Exacerbating the problem is the whole testing, rating, certification and listing process. What most folks may not realize is that the role of testing and rating is different from the role of listing when it comes to approvals. For example, a manufacturer creates a product, finds an approved standard(s) to test the product to, then finds an approved testing lab that is certified to test to that standard(s). The lab may or may not have listing services and if not, the manufacturer will have to take their third party test reports to a listing agency for review, approval and listing service. Some manufacturers prefer to have their products listed by IAPMO or ICC for recognition purposes, even when certain approved testing labs also offer listing services, i.e. NSF.
The problem is that a listing agency isn't obligated to share the details of any particular listing beyond a simple acknowledgement that the product has been reviewed along with the standard that it was third party tested to and so long as an approved agency was used, the standard is accepted by the model plumbing code(s), and the product passed the requirements for certification in the standard, the listing agency need only put that in writing.
But, what if a standard has multiple options for certification? Is that even possible? Yes. Let me explain further. Currently PDI G101 allows a manufacturer to test and rate their HGI to just 13 increments and as long as the unit meets the minimum average efficiency of 90 percent and holds a minimum of 2-1/4 pounds of grease for each gallon per minute of flow rate, the HGI will be certified at a Rated Grease Capacity. But, what if the manufacturer tested another HGI to its breakdown point, while still meeting the minimum efficiency and grease storage capacity - how would anyone know the difference? That's the problem right there. The listing agency doesn't distinguish between the two different ratings when conducting their evaluation - both units pass and therefore both are listed.
It gets even more fun for jurisdictions. For example, what if under the ASME A112.14.3 standard a manufacturer wanted to test an interceptor using a vented external flow control (Type A) and another interceptor using an integral (built-in) flow control (Type C). So long as both units pass the minimum performance criteria of the standard, there is no distinction on the listing between the two types of devices.
What jurisdictions need is a kind of consumer reports analysis that can take all of this confusing certification and listing information and condense it down and make it understandable so everyone knows how an interceptor was actually tested and rated, how it performed, whether it was tested to breakdown or something short, whether it must have a vented external flow control or is approved with an integral flow control, etc, etc, etc.
I think I have a solution, so stay tuned.