User Guide

Frequently Asked Questions
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Frequently Asked Questions
Following are just a few of the common terms and questions we receive regarding Grease
Management. This list is also available on our website (enduraXL.com) where you can also
submit your own questions for us to answer and if there are common questions arising we
will add those to the digital list.
How do I size a Grease Interceptor correctly?
A grease Interceptor can be sized using two primary methods
Flow Rate – When sizing by Flow Rate there are two sub sections
Fixture Capacity: Most commonly used and recommended method for Hydromechanical Grease Interceptors.
This method looks at the maximum capacity of xtures connected to the interceptor and the time taken to
discharge that volume of wastewater through the interceptor. Units are expressed in Gallons Per Minute (gpm).
Calculation takes 75% of maximum capacity of all xtures and based on a 1 or 2 minute period of time taken
to discharge, results in a gallons per minute ow rate. This number is rounded up to the next available size of
interceptor, i.e. 16.7gpm become a 20gpm Grease Interceptor.
To simplify sizing Canplas oers an online and mobile
friendly sizing calculator at www.endurainterceptor.com
Note: Capacity sizing is typically applied to gravity grease interceptors (GGI) resulting in a liquid capacity that is substantially
greater than an equivalent hydromechanical GI. An HGI due to its qualied eciency and grease capacity at breakdown
(when eciency falls below 90%) results in actual grease capacity that is operationally equivalent to a GGI that is 5-6
times that of the HGI.
Pipe Size:
Pipe
Diameter
Maximum
Flow Rate
(gpm)
Size of interceptor
1-minute drain
period (gpm)
Size of interceptor
2-minute drain period
(gpm)
2-inch 20 20 10
3-inch 60 75 35
4-inch 125 150 75
Capacity: Based on the volume of wastewater discharge (gallons) into the interceptor expressed as discharge xture units
(DFU’s). DFU’s are identied in the currently published issue of Uniform Plumbing Code Ch.7 based on occupancy or use.
Floor Drains & Floor Sinks: Take
the volume of water produced by the
number of hose bibs (ie 1.5-2.0 gpm per
3/4” faucet)
Example: Commercial sink with food
waste with 1-1/2” trap, plus mop sink and
special purpose sink 2” trap.
3+3+3=9 (DFU)
Referencing table below 9 DFU will require
750 gallon min. interceptor volume.
Drainage
Fixture
Units
Interceptor
Volume
(min.)
8 500
21 750
35 1000
90 1250
172 1500
216 2000
Fixture Fixture Units Public
Floor drain, non-emergency 2
Special purpose sink w/1-1/2” trap 3
Special purpose sink w/2” trap 4
Special purpose sink w/3” trap 6
Commercial sink w/food waste w/
1-1/2” trap
3
Bar Sink 2
Mop Sink 3
Laundry Sink 2