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WATER AUTHORITY OF FIJI
FABRICATION & INSTALLATION OF GREASE TRAPS AND UNDERGROUND
GREASE INTERCEPTORS
2017
Clean Water and Sanitation for a Better Life
• A larger sized grease interceptor can be used. For further specifications
• Two or more grease interceptors can be installed in series to cater for the
The first baffle shall extend from the cover above the water level and down to be
The second baffle shall extend from the inside floor of the interceptor and up to
The above mentioned specifications is for the 1000 litre underground grease interceptor. Refer to Table 3.2 for specifications for larger Grease Interceptors.
wishes to use on their property must first be approved by the WAF.
cal to the fixture(s) being served.
• Ensure that it is as close as possible to the building.
• Ensure that it can withstand the external loads being placed on it
• If it is buried and the top of the interceptor is level with the ground
• A protective wall must be erected around it at least 200mm above the
• It must be at least 200mm above the ground level to prevent water run
• Ensure that it can withstand the external loads being placed on it
• A protective wall must be erected around it at least 200mm above the
• If it is partially buried then it must be at least 200mm above the
• If it is placed in an area with limited space then ensure that it has gas
• Two vents, a minimum of 100mm in diameter, open to the atmosphere
• An induct vent, at low or high level directly off the interceptor at the
• An educt vent, at a high level also directly off the interceptor at the
• The educt Vent diverted to at least 2 meters above the highest point of
• Exterior flaps on the openings of the induct and educt vents.
• Inlet compartment• Separation compartment
• Outlet compartment.
e) Certificate of Compliance A certificate of compliance must be provided by the licensed plumbers after
• Remove lid from the top of the interceptor.• Place suction hose into the compartment.• Begin pump out.• Scrape the inside of the compartment to remove FOG that is stuck to
• Continue pump out until all FOG is removed.• DO NOT use degreasers to clean out the grease trap.• DO NOT use hot water to clean out the grease trap as this will only
make the solidified FOG soluble and harder to remove.
HANDBOOK
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors 1
ACKNOWLEDGEMENT
This handbook is an important tool for people and businesses in the plumbing industry. This serves a great need for the restaurant industry where it is manda-tory to have grease traps or grease interceptors. The success and final outcome of this handbook required guidance and assistance from many people. We acknowledge and express our sincere gratitude towards the following people who have greatly assisted in compiling this handbook.
• Fiji National University, especially Mr Luke Diloi who is also the President for Fiji Institute of Plumbing and Mr Salabogi Mavoa who is the Associate Dean for College of Engineering, Science and Technology
• Town and City Councils • GHD Capacity Building Consultancy.• Sydney Water Corporation, Australia.• Planning and Design Team of Water Authority of Fiji • All the participants who took part in the Fabrication and Installation of
grease trap consultation workshop for contributing bright ideas towards the handbook.
We would like to give our special acknowledgement to the Water Authority of Fiji’s management team for making it possible to publish this handbook.
2
TABLE OF CONTENTS
Pages Acknowledgment 1 Preface 2 1.Background 2.Objectives
3
3.Designs
4
3.3 Designs 3.3.1 Under sink grease trap design
5 - 9
3.3.2 Guidelines 3.3.2.1 Under Sink Grease Trap
10 – 13
Table -Dimensions for Underground Grease Interceptors
18 -19
4.1 FOG Management
20 -24
14 - 17
26-27
• A larger sized grease interceptor can be used. For further specifications
• Two or more grease interceptors can be installed in series to cater for the
The first baffle shall extend from the cover above the water level and down to be
The second baffle shall extend from the inside floor of the interceptor and up to
The above mentioned specifications is for the 1000 litre underground grease interceptor. Refer to Table 3.2 for specifications for larger Grease Interceptors.
wishes to use on their property must first be approved by the WAF.
cal to the fixture(s) being served.
• Ensure that it is as close as possible to the building.
• Ensure that it can withstand the external loads being placed on it
• If it is buried and the top of the interceptor is level with the ground
• A protective wall must be erected around it at least 200mm above the
• It must be at least 200mm above the ground level to prevent water run
• Ensure that it can withstand the external loads being placed on it
• A protective wall must be erected around it at least 200mm above the
• If it is partially buried then it must be at least 200mm above the
• If it is placed in an area with limited space then ensure that it has gas
• Two vents, a minimum of 100mm in diameter, open to the atmosphere
• An induct vent, at low or high level directly off the interceptor at the
• An educt vent, at a high level also directly off the interceptor at the
• The educt Vent diverted to at least 2 meters above the highest point of
• Exterior flaps on the openings of the induct and educt vents.
• Inlet compartment• Separation compartment
• Outlet compartment.
e) Certificate of Compliance A certificate of compliance must be provided by the licensed plumbers after
• Remove lid from the top of the interceptor.• Place suction hose into the compartment.• Begin pump out.• Scrape the inside of the compartment to remove FOG that is stuck to
• Continue pump out until all FOG is removed.• DO NOT use degreasers to clean out the grease trap.• DO NOT use hot water to clean out the grease trap as this will only
make the solidified FOG soluble and harder to remove.
4.2 Minimum Pretreatment Requirement for Food Proccesses
3.3.3 Underground Grease Interceptor
3.3.4 Guidelines3.3.4.1 Underground Grease Interceptor4.Appendices4.1 FOG Management 25
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors 3
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors
PREFACE
Grease traps and grease interceptors are devices designed to separate the Fats, Oil and Grease (FOG) and solids prior to discharge into a wastewater disposal system. It protects the wastewater system from blockages due to FOG and solid waste from food preparation areas. Through various inspections, workshops and presentations, it was found by WAF that there was poor or improper grease trap and grease intercep-tor designs and installations. The majority of the small restaurant owners were not aware of grease trap designs, its purpose, the size required or even the maintenance. Many restaurants had grease traps or grease interceptors but were not maintaining them, while others had undersized designs or poor pipework. This handbook details the designs of the passive grease trap and grease interceptors. It informs the user on the fabrication, materials, sizing and manufacturing. It also outlines the installation process that includes; positioning, venting and piping. This handbook also includes; the frequency of clean outs, responsibility for clean outs and disposal, clean out methods and disposal methods of FOG. These designs are a mandatory guideline for new Grease trap designs and are accept-able if it is inspected by Water Authority of Fiji technician and is found to be function-ing and maintained properly.……………………………………………………………………………………………………………………………………….........Prepared By: Assisted By: _______________ & ________________ _______________________Andrew Kirkwood Hillary Fisher Komal DeviGHD Consultant Graduate Engineer Team Leader Liquid Trade Waste Water Authority of Fiji Water Authority of Fiji
Reviewed By: Checked By:
_______________________ ________________________Rahul Sharma Danilo de AsaGraduate Engineer Senior Engineer Water Authority of Fiji Water Authority of Fiji
Recommended for Approval By Approved By
________________________ _________________________Seru Soderberg Opetaia Ravai Acting GM Planning and Design Chief Executive Officer Water Authority of Fiji Water Authority of Fiji
1. BACKGROUND
Proper management of Fats, Oils and Grease (FOG) produced by the discharge from kitchens and food preparation areas is a problem for the Food Industry and for the Water Authority of Fiji's Wastewater Operations. The solids and FOG should not be discharged in waste water or sewer lines as it causes blockages which is an issue for WAF's sewer reticulation system and the treatment plants that eventually receive the discharge.
Grease Traps and Interceptors are designed to separate the FOG and solids from the grey water in discharge from kitchens and food preparation areas. The traps use the physical principal that fats, oils and grease are lighter than water and will rise to the top of a water surface and heavy debris will fall to the bottom of the trap when the mixture is allowed to settle for a period of time in quiet conditions. The longer the wastewater stays in the trap, the better the separation.
However, as the amount of retained grease and solids increases, the working capacity of the trap decreases, retention time decreases and physical separation decreases, resulting in the pass through of solids, fats, oils and grease. To prevent this, grease traps and interceptors have to be regularly maintained by removing both the top grease layer and the settled solids at the base of the trap.
There are two ways to remove the grease layer and settled solids. Either by a. manually removing it or b. through pump outs Option (b) is the approved method especially for the larger grease traps or under-ground grease interceptors. Pump outs must be done several times over a specified period (usually daily for small grease traps and quarterly for the larger ones) depend-ing on the requirements of the Trade Waste Policy and local government regulations.
2. OBJECTIVE Upgrade the current Grease Trap design used by the Restaurant Industry in Fiji and ensure the final designs and guidelines is a standard for installing new units for businesses and residents.
2
• A larger sized grease interceptor can be used. For further specifications
• Two or more grease interceptors can be installed in series to cater for the
The first baffle shall extend from the cover above the water level and down to be
The second baffle shall extend from the inside floor of the interceptor and up to
The above mentioned specifications is for the 1000 litre underground grease interceptor. Refer to Table 3.2 for specifications for larger Grease Interceptors.
wishes to use on their property must first be approved by the WAF.
cal to the fixture(s) being served.
• Ensure that it is as close as possible to the building.
• Ensure that it can withstand the external loads being placed on it
• If it is buried and the top of the interceptor is level with the ground
• A protective wall must be erected around it at least 200mm above the
• It must be at least 200mm above the ground level to prevent water run
• Ensure that it can withstand the external loads being placed on it
• A protective wall must be erected around it at least 200mm above the
• If it is partially buried then it must be at least 200mm above the
• If it is placed in an area with limited space then ensure that it has gas
• Two vents, a minimum of 100mm in diameter, open to the atmosphere
• An induct vent, at low or high level directly off the interceptor at the
• An educt vent, at a high level also directly off the interceptor at the
• The educt Vent diverted to at least 2 meters above the highest point of
• Exterior flaps on the openings of the induct and educt vents.
• Inlet compartment• Separation compartment
• Outlet compartment.
e) Certificate of Compliance A certificate of compliance must be provided by the licensed plumbers after
• Remove lid from the top of the interceptor.• Place suction hose into the compartment.• Begin pump out.• Scrape the inside of the compartment to remove FOG that is stuck to
• Continue pump out until all FOG is removed.• DO NOT use degreasers to clean out the grease trap.• DO NOT use hot water to clean out the grease trap as this will only
make the solidified FOG soluble and harder to remove.
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors 5
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors
4
3
3. DESIGNS
3.3 DESIGNS
3.3.1 UNDER SINK GREASE TRAP DESIGN
Please refer to the Drawings on the next page
STANDARD DESIGN
WAF has developed standard designs for:1. An Under the sink Grease trap2. An Underground Grease Interceptor
Businesses with seating of between 1 - 69 seats will need to install an underground grease interceptor with a volume of 1000 liters minimum. This interceptor can be fabricated to fit above or below ground.
The under sink grease traps are ONLY for Coffee lounges and Snack Bars. It will have a total volume of 200 liters.
This document includes guidelines on the Fabrication, Installation and Maintenance for each design. It is the minimum requirements and can be used as a guideline for Manufacturers that wish to produce the traps in bulk for distribution.
• A larger sized grease interceptor can be used. For further specifications
• Two or more grease interceptors can be installed in series to cater for the
The first baffle shall extend from the cover above the water level and down to be
The second baffle shall extend from the inside floor of the interceptor and up to
The above mentioned specifications is for the 1000 litre underground grease interceptor. Refer to Table 3.2 for specifications for larger Grease Interceptors.
wishes to use on their property must first be approved by the WAF.
cal to the fixture(s) being served.
• Ensure that it is as close as possible to the building.
• Ensure that it can withstand the external loads being placed on it
• If it is buried and the top of the interceptor is level with the ground
• A protective wall must be erected around it at least 200mm above the
• It must be at least 200mm above the ground level to prevent water run
• Ensure that it can withstand the external loads being placed on it
• A protective wall must be erected around it at least 200mm above the
• If it is partially buried then it must be at least 200mm above the
• If it is placed in an area with limited space then ensure that it has gas
• Two vents, a minimum of 100mm in diameter, open to the atmosphere
• An induct vent, at low or high level directly off the interceptor at the
• An educt vent, at a high level also directly off the interceptor at the
• The educt Vent diverted to at least 2 meters above the highest point of
• Exterior flaps on the openings of the induct and educt vents.
• Inlet compartment• Separation compartment
• Outlet compartment.
e) Certificate of Compliance A certificate of compliance must be provided by the licensed plumbers after
• Remove lid from the top of the interceptor.• Place suction hose into the compartment.• Begin pump out.• Scrape the inside of the compartment to remove FOG that is stuck to
• Continue pump out until all FOG is removed.• DO NOT use degreasers to clean out the grease trap.• DO NOT use hot water to clean out the grease trap as this will only
make the solidified FOG soluble and harder to remove.
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors 7
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors
6
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• A larger sized grease interceptor can be used. For further specifications
• Two or more grease interceptors can be installed in series to cater for the
The first baffle shall extend from the cover above the water level and down to be
The second baffle shall extend from the inside floor of the interceptor and up to
The above mentioned specifications is for the 1000 litre underground grease interceptor. Refer to Table 3.2 for specifications for larger Grease Interceptors.
wishes to use on their property must first be approved by the WAF.
cal to the fixture(s) being served.
• Ensure that it is as close as possible to the building.
• Ensure that it can withstand the external loads being placed on it
• If it is buried and the top of the interceptor is level with the ground
• A protective wall must be erected around it at least 200mm above the
• It must be at least 200mm above the ground level to prevent water run
• Ensure that it can withstand the external loads being placed on it
• A protective wall must be erected around it at least 200mm above the
• If it is partially buried then it must be at least 200mm above the
• If it is placed in an area with limited space then ensure that it has gas
• Two vents, a minimum of 100mm in diameter, open to the atmosphere
• An induct vent, at low or high level directly off the interceptor at the
• An educt vent, at a high level also directly off the interceptor at the
• The educt Vent diverted to at least 2 meters above the highest point of
• Exterior flaps on the openings of the induct and educt vents.
• Inlet compartment• Separation compartment
• Outlet compartment.
e) Certificate of Compliance A certificate of compliance must be provided by the licensed plumbers after
• Remove lid from the top of the interceptor.• Place suction hose into the compartment.• Begin pump out.• Scrape the inside of the compartment to remove FOG that is stuck to
• Continue pump out until all FOG is removed.• DO NOT use degreasers to clean out the grease trap.• DO NOT use hot water to clean out the grease trap as this will only
make the solidified FOG soluble and harder to remove.
5
3
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors 9
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors
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• A larger sized grease interceptor can be used. For further specifications
• Two or more grease interceptors can be installed in series to cater for the
The first baffle shall extend from the cover above the water level and down to be
The second baffle shall extend from the inside floor of the interceptor and up to
The above mentioned specifications is for the 1000 litre underground grease interceptor. Refer to Table 3.2 for specifications for larger Grease Interceptors.
wishes to use on their property must first be approved by the WAF.
cal to the fixture(s) being served.
• Ensure that it is as close as possible to the building.
• Ensure that it can withstand the external loads being placed on it
• If it is buried and the top of the interceptor is level with the ground
• A protective wall must be erected around it at least 200mm above the
• It must be at least 200mm above the ground level to prevent water run
• Ensure that it can withstand the external loads being placed on it
• A protective wall must be erected around it at least 200mm above the
• If it is partially buried then it must be at least 200mm above the
• If it is placed in an area with limited space then ensure that it has gas
• Two vents, a minimum of 100mm in diameter, open to the atmosphere
• An induct vent, at low or high level directly off the interceptor at the
• An educt vent, at a high level also directly off the interceptor at the
• The educt Vent diverted to at least 2 meters above the highest point of
• Exterior flaps on the openings of the induct and educt vents.
• Inlet compartment• Separation compartment
• Outlet compartment.
e) Certificate of Compliance A certificate of compliance must be provided by the licensed plumbers after
• Remove lid from the top of the interceptor.• Place suction hose into the compartment.• Begin pump out.• Scrape the inside of the compartment to remove FOG that is stuck to
• Continue pump out until all FOG is removed.• DO NOT use degreasers to clean out the grease trap.• DO NOT use hot water to clean out the grease trap as this will only
make the solidified FOG soluble and harder to remove.
5
3
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors 11
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors
10
3
3.3.2 GUIDELINES
3.3.2.1 Under Sink Grease Trap
A. FABRICATION:
a) Total Volume The Under sink Grease Trap shall have a total volume of 200 Litres with
a working capacity of 150 Litres and shall ONLY be used for Snack Bars and Coffee Lounges.
b) SizingThe scaled version of the design will use a ratio of surface area to volume.
E.g. The trap is 0.9m x 0.5m x 0.5m and has a:
Surface Area = 2 x [(L x W) + (L x H) + (W x H)] = 2 x [(0.9 x 0.5) + (0.9 x 0.5) + (0.5 x 0.5)] = 2.3 m2,
Total Volume = L x W x H =0.9 x 0.5x 0.5 = 0.225 m3,
And therefore a surface area to volume ratio of
SA: V = 2.3m2:0.225m3 = 2.3:0.225 = 10.22:1 = 10.22/1 = 10.22 ≈ 10
The ratio must be reduced until the volume (V) is 1.
For situations where the FOG to separated exceeds the working capacity of 150 Litres and is less than 700 Litres, the design for the 1000 litre underground grease interceptor MUST be used.
c) Materials The grease trap must be made from a material that does not corrode and
is suitable for in kitchen use. (i.e. Materials specified for food equipment such as food grade Stainless
Steel Type 316 or HDPE).
If alternative materials wish to be used to fabricate the traps then approval must first be obtained from WAF.
d) Manufacturing• The First baffle shall extend from at least 50mm above the water level to
within 50mm of the inside floor of the trap. • The Second baffle shall extend from the inside floor of the trap to within
100mm of the top of the trap. • The Inlet shall be at least 50mm from the top on the inside of the trap
and the outlet pipe at least 150mm from the inside base of the trap.
e) Alternative Designs Any alternative designs for a under the sink grease trap that a business
may wish to use for their food preparation areas must first be approved by the WAF.
B. INSTALLATION:
a) Positioning the Grease Trap• Grease traps shall be placed as close as practical to the fixture(s) being
served. • It shall be located where it is easily accessible at all times for inspection,
cleaning, and removal of accumulated grease. • It can be placed outdoors if there is a limited amount of space inside the
food preparation area.
b) Piping• All Pipe works must be completed by a licensed plumber.• There shall be no piping inside the Grease trap. • Inlet and outlet piping must be as per the regulations set out by the Fiji National Building Codes and the WAF Grease Trap Design Standards and Guidelines.
c) Venting• No Venting required
d) Access to the Trap• Access to the grease trap shall be through the lid.• Lids can be either left as it is on the trap or clamped down. • For areas in which the trap may be encountered by the public, the trap
lid must be securely fastened to prevent tampering.
e) Certificate of Compliance • A certificate of compliance must be provided by the licensed plumber-
safter the installation of the trap.
• These 200 litre grease traps should be cleaned out on a daily basis. • Traps with a Volume greater than 200 litres and less than 500 litres must
• Businesses must keep a record of the clean outs done. If pump outs are
• First scrape the top layer of FOG off the surface on the inside of the trap
• Using the handles of the perforated tray, gently lift the tray up and hold to allow for the effluent water to drain through it.
• Once drained remove the tray and place contents into a sealed plastic
• Scrape the inside of the trap to remove FOG that is stuck to its inside
• DO NOT use degreasers to clean out the grease trap.• DO NOT use hot water to clean out the grease trap as this will only make
the solidified FOG soluble and harder to remove.
• Remove lid from the top of the trap.• Place suction hose into the trap.• Begin pump out of the trap.
• Scrape the inside of the trap to remove FOG that is stuck to its inside
• Continue pump out until all FOG is removed• DO NOT use degreasers to clean out the grease trap.• DO NOT use hot water to clean out the grease trap as this will only make
the solidified FOG soluble and harder to remove.
• A larger sized grease interceptor can be used. For further specifications
• Two or more grease interceptors can be installed in series to cater for the
The first baffle shall extend from the cover above the water level and down to be
The second baffle shall extend from the inside floor of the interceptor and up to
The above mentioned specifications is for the 1000 litre underground grease interceptor. Refer to Table 3.2 for specifications for larger Grease Interceptors.
wishes to use on their property must first be approved by the WAF.
cal to the fixture(s) being served.
• Ensure that it is as close as possible to the building.
• Ensure that it can withstand the external loads being placed on it
• If it is buried and the top of the interceptor is level with the ground
• A protective wall must be erected around it at least 200mm above the
• It must be at least 200mm above the ground level to prevent water run
• Ensure that it can withstand the external loads being placed on it
• A protective wall must be erected around it at least 200mm above the
• If it is partially buried then it must be at least 200mm above the
• If it is placed in an area with limited space then ensure that it has gas
• Two vents, a minimum of 100mm in diameter, open to the atmosphere
• An induct vent, at low or high level directly off the interceptor at the
• An educt vent, at a high level also directly off the interceptor at the
• The educt Vent diverted to at least 2 meters above the highest point of
• Exterior flaps on the openings of the induct and educt vents.
• Inlet compartment• Separation compartment
• Outlet compartment.
e) Certificate of Compliance A certificate of compliance must be provided by the licensed plumbers after
• Remove lid from the top of the interceptor.• Place suction hose into the compartment.• Begin pump out.• Scrape the inside of the compartment to remove FOG that is stuck to
• Continue pump out until all FOG is removed.• DO NOT use degreasers to clean out the grease trap.• DO NOT use hot water to clean out the grease trap as this will only
make the solidified FOG soluble and harder to remove.
(i.e. Materials specified for food equipment such as food grade Stainless
first be obtained from WAF.
• The First baffle shall extend from at least 50mm above the water level to
• The Second baffle shall extend from the inside floor of the trap to within
• The Inlet shall be at least 50mm from the top on the inside of the trap
may wish to use for their food preparation areas must first be approved
• Grease traps shall be placed as close as practical to the fixture(s) being
• It shall be located where it is easily accessible at all times for inspection,
• It can be placed outdoors if there is a limited amount of space inside the
• All Pipe works must be completed by a licensed plumber.• There shall be no piping inside the Grease trap. • Inlet and outlet piping must be as per the regulations set out by the Fiji
• No Venting required
• Access to the grease trap shall be through the lid.• Lids can be either left as it is on the trap or clamped down. • For areas in which the trap may be encountered by the public, the trap
e) Certificate of Compliance • A certificate of compliance must be provided by the licensed plumber
5
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Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors 13
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors
12
3
C. MAINTENANCE:
a) Frequency of Clean Outs• These 200 litre grease traps should be cleaned out on a daily basis. • Traps with a Volume greater than 200 litres and less than 500 litres must
be cleaned every second or third day.• Businesses must keep a record of the clean outs done. If pump outs are
done, then the receipts for the pump out chargers must be kept as this is proof of frequent cleaning.
b) Responsibility for Clean Outs and DisposalIt is the responsibility of the Liquid Trade Waste Permit Holders to ensure that the clean out of the Grease traps are done on a regular basis and disposed of prop-erly.
It is NOT the responsibility of WAF or the relevant authorities to do this. However, it is WAFs and other authorities’ responsibility to monitor the businesses and residents to ensure that this is done regularly and properly.
c) Clean Out Methods
Clean out of the grease traps can be done manually or through pump outs.
For manual removal:• First scrape the top layer of FOG off the surface on the inside of the trap
and place in a sealed plastic bag. Continue this until all the FOG on the surface is removed.
• Using the handles of the perforated tray, gently lift the tray up and hold to allow for the effluent water to drain through it.
• Once drained remove the tray and place contents into a sealed plastic bag.
• Scrape the inside of the trap to remove FOG that is stuck to its inside surface and place into the sealed plastic bag.
• DO NOT use degreasers to clean out the grease trap.• DO NOT use hot water to clean out the grease trap as this will only make
the solidified FOG soluble and harder to remove.
For Pump outs:• Remove lid from the top of the trap.• Place suction hose into the trap.• Begin pump out of the trap.
• Scrape the inside of the trap to remove FOG that is stuck to its inside surface.
• Continue pump out until all FOG is removed• DO NOT use degreasers to clean out the grease trap.• DO NOT use hot water to clean out the grease trap as this will only make
the solidified FOG soluble and harder to remove.
d) Disposal of FOGIf businesses incorporate the under the sink grease trap with an underground grease interceptor, then the removed FOG from the smaller units can be put into the underground interceptor and pumped out when the underground interceptor needs to be cleaned. The removed FOG can then be taken to the Sewerage Treat-ment Plant for disposal.
• A larger sized grease interceptor can be used. For further specifications
• Two or more grease interceptors can be installed in series to cater for the
The first baffle shall extend from the cover above the water level and down to be
The second baffle shall extend from the inside floor of the interceptor and up to
The above mentioned specifications is for the 1000 litre underground grease interceptor. Refer to Table 3.2 for specifications for larger Grease Interceptors.
wishes to use on their property must first be approved by the WAF.
cal to the fixture(s) being served.
• Ensure that it is as close as possible to the building.
• Ensure that it can withstand the external loads being placed on it
• If it is buried and the top of the interceptor is level with the ground
• A protective wall must be erected around it at least 200mm above the
• It must be at least 200mm above the ground level to prevent water run
• Ensure that it can withstand the external loads being placed on it
• A protective wall must be erected around it at least 200mm above the
• If it is partially buried then it must be at least 200mm above the
• If it is placed in an area with limited space then ensure that it has gas
• Two vents, a minimum of 100mm in diameter, open to the atmosphere
• An induct vent, at low or high level directly off the interceptor at the
• An educt vent, at a high level also directly off the interceptor at the
• The educt Vent diverted to at least 2 meters above the highest point of
• Exterior flaps on the openings of the induct and educt vents.
• Inlet compartment• Separation compartment
• Outlet compartment.
e) Certificate of Compliance A certificate of compliance must be provided by the licensed plumbers after
• Remove lid from the top of the interceptor.• Place suction hose into the compartment.• Begin pump out.• Scrape the inside of the compartment to remove FOG that is stuck to
• Continue pump out until all FOG is removed.• DO NOT use degreasers to clean out the grease trap.• DO NOT use hot water to clean out the grease trap as this will only
make the solidified FOG soluble and harder to remove.
3.3.3 UNDERGROUND GREASE INTERCEPTOR
Please refer to the Drawings on the next page
5
3
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors 15
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors
14
3
• A larger sized grease interceptor can be used. For further specifications
• Two or more grease interceptors can be installed in series to cater for the
The first baffle shall extend from the cover above the water level and down to be
The second baffle shall extend from the inside floor of the interceptor and up to
Plan
Sca
le:
1:1
0
D D
B
A
DL
LD
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to
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ictu
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NOTE
S:So
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abili
zatio
n:
Soil
aro
und tra
p to b
e c
om
pact
ed to
95%
inte
nsi
ty.
C
oncr
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blin
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eneath
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ase
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D
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reve
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ate
r se
epage.
Vent
(Ø=100mm)
Insp
ect
ion
Poi
nt(Ø=100mm)
Insp
ect
ion
Poin
t(Ø=100mm)
Vent
(Ø=100mm)
The above mentioned specifications is for the 1000 litre underground grease interceptor. Refer to Table 3.2 for specifications for larger Grease Interceptors.
wishes to use on their property must first be approved by the WAF.
cal to the fixture(s) being served.
• Ensure that it is as close as possible to the building.
• Ensure that it can withstand the external loads being placed on it
• If it is buried and the top of the interceptor is level with the ground
• A protective wall must be erected around it at least 200mm above the
• It must be at least 200mm above the ground level to prevent water run
• Ensure that it can withstand the external loads being placed on it
• A protective wall must be erected around it at least 200mm above the
• If it is partially buried then it must be at least 200mm above the
• If it is placed in an area with limited space then ensure that it has gas
• Two vents, a minimum of 100mm in diameter, open to the atmosphere
• An induct vent, at low or high level directly off the interceptor at the
• An educt vent, at a high level also directly off the interceptor at the
• The educt Vent diverted to at least 2 meters above the highest point of
• Exterior flaps on the openings of the induct and educt vents.
• Inlet compartment• Separation compartment
• Outlet compartment.
e) Certificate of Compliance A certificate of compliance must be provided by the licensed plumbers after
• Remove lid from the top of the interceptor.• Place suction hose into the compartment.• Begin pump out.• Scrape the inside of the compartment to remove FOG that is stuck to
• Continue pump out until all FOG is removed.• DO NOT use degreasers to clean out the grease trap.• DO NOT use hot water to clean out the grease trap as this will only
make the solidified FOG soluble and harder to remove.
5
3
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors 17
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors
16
3
• A larger sized grease interceptor can be used. For further specifications
• Two or more grease interceptors can be installed in series to cater for the
The first baffle shall extend from the cover above the water level and down to be
The second baffle shall extend from the inside floor of the interceptor and up to
E2 E1
DD
DL
DL
C
A
GE2
ElevationS
cale
: 1:1
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ire
Refe
r to T
ab 3
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P
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End ElevationS
cale
: 1:1
5
(Ø=100mm)
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ox 1
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C:\U
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Pic
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NO
TES:Soil Stabilization:
So
il aro
un
d tra
p to
be
co
mp
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95
% in
ten
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.
C
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D.D
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R.S
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RM
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ISH
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Vent (H
) (Ø=100mm)
Inspectio
n P
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Vent (H
) (Ø=100mm)
Inspectio
n P
oint(Ø=100mm)
Vent
(Ø=100mm)
Vent
(Ø=100mm)
Inspectio
n P
oint
Plan
Sca
le:
1:1
0
B
A
D
F
inle
toutlet
LID
CO
VE
RLID
CO
VE
R
LID
CO
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pu
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of
Th
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sla
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33
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4W
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rity
off
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PR
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CT
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S.S
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EN
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PLA
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& D
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IGN
C:\
Use
rs\P
ub
lic\P
ictu
res\S
am
ple
Pic
ture
s\L
OG
O.p
ng
W0
0/0
0/0
0
NO
TES:
Soil
Stab
iliza
tion:
S
oil
aro
un
d t
rap
to
be
co
mp
acte
d t
o
95
% in
ten
sity.
C
on
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te b
lind
ing
of
50
mm
be
ne
ath
the
ba
se
of
the
str
uctu
re.
D
am
p P
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f C
ou
rse
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ath
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uctu
re t
o p
reve
nt
wa
ter
se
ep
ag
e.
03
00
Vent
(Ø=100mm)
Vent
(Ø=100mm)
The above mentioned specifications is for the 1000 litre underground grease interceptor. Refer to Table 3.2 for specifications for larger Grease Interceptors.
wishes to use on their property must first be approved by the WAF.
cal to the fixture(s) being served.
• Ensure that it is as close as possible to the building.
• Ensure that it can withstand the external loads being placed on it
• If it is buried and the top of the interceptor is level with the ground
• A protective wall must be erected around it at least 200mm above the
• It must be at least 200mm above the ground level to prevent water run
• Ensure that it can withstand the external loads being placed on it
• A protective wall must be erected around it at least 200mm above the
• If it is partially buried then it must be at least 200mm above the
• If it is placed in an area with limited space then ensure that it has gas
• Two vents, a minimum of 100mm in diameter, open to the atmosphere
• An induct vent, at low or high level directly off the interceptor at the
• An educt vent, at a high level also directly off the interceptor at the
• The educt Vent diverted to at least 2 meters above the highest point of
• Exterior flaps on the openings of the induct and educt vents.
• Inlet compartment• Separation compartment
• Outlet compartment.
e) Certificate of Compliance A certificate of compliance must be provided by the licensed plumbers after
• Remove lid from the top of the interceptor.• Place suction hose into the compartment.• Begin pump out.• Scrape the inside of the compartment to remove FOG that is stuck to
• Continue pump out until all FOG is removed.• DO NOT use degreasers to clean out the grease trap.• DO NOT use hot water to clean out the grease trap as this will only
make the solidified FOG soluble and harder to remove.
5
3
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors 19
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors
18
3
• A larger sized grease interceptor can be used. For further specifications
• Two or more grease interceptors can be installed in series to cater for the
The first baffle shall extend from the cover above the water level and down to be
The second baffle shall extend from the inside floor of the interceptor and up to
Ta
ble
3.2
(c
on
tin
ue
d)
Typ
e
I (m
m)
J (
mm
) K
(m
m)
L (
mm
)
M1
/ M
2
(mm
)
N1
/ N
2
(mm
)
O1
/ O
2
(mm
) P
(m
m)
Q (
mm
) W
L (
mm
)
1
250
350
300
50
650 /
100
550 /
200
100 /
100
200
250
550 -
600
2
300
450
350
100
700 /
200
600 /
300
150 /
150
200
250
800 -
850
3
350
700
450
100
750 /
200
650 /
300
150 /
150
200
250
750 -
800
4
350
700
450
100
900 /
200
800 /
300
150 /
150
200
250
900 -
950
5
350
700
450
100
1050
/
200
950 /
300
150 /
150
200
250
1050
- 1
100
Ta
ble
3.2
- Dim
ensions for
Underground G
rease Interceptors
(1000 - 5000 Liters)
Typ
e
To
tal
Vo
lum
e
(Litres)
Dim
ensio
n
on
Grease
Intercep
tor
A (m
m)
B (m
m)
C (m
m)
D (m
m)
E2 / E
1
(mm
) F
(mm
) G
(mm
) H
(mm
)
Reb
ar
Typ
e
Reb
ar
Th
ickness
(mm
)
Co
ncrete
Stren
gth
(MP
a)
1 1000
Inside 1000
800 750
100 100 / 50
100 100
100 665
mesh
5.3 25
Outside
1200 1000
900
2 2000
Inside 1300
1000 900
100 100 / 100
100 100
100 F
81
mesh
8 25
Outside
1500 1200
1100
3 3000
Inside 1700
1000 950
150 150 / 100
100 100
100 F
81
Mesh
8 32
Outside
2000 1300
1200
4 4000
Inside 1700
1200 1100
150 150 / 100
100 100
100 F
81
Mesh
8 32
Outside
2000 1500
1350
5 5000
Inside 1700
1400 1250
150 150 / 100
100 100
100 F
81
Mesh
8 32
Outside
2000 1700
1500
Not
e: S
oil S
tabi
lizat
ion
• S
oil
aro
un
d t
he G
reas
e I
nte
rcep
tor
is t
o b
e c
om
pac
ted
to
95
% D
en
sity
.•
Co
ncr
ete
bin
din
g o
f 5
0m
m b
en
eat
h t
he b
ase o
f th
e G
reas
e In
terc
ep
tor.
•
Dam
p p
roo
f co
urs
e u
nd
ern
eat
h t
he G
reas
e In
terc
ep
tor
to p
reve
nt
see
pag
e.
The above mentioned specifications is for the 1000 litre underground grease interceptor. Refer to Table 3.2 for specifications for larger Grease Interceptors.
wishes to use on their property must first be approved by the WAF.
cal to the fixture(s) being served.
• Ensure that it is as close as possible to the building.
• Ensure that it can withstand the external loads being placed on it
• If it is buried and the top of the interceptor is level with the ground
• A protective wall must be erected around it at least 200mm above the
• It must be at least 200mm above the ground level to prevent water run
• Ensure that it can withstand the external loads being placed on it
• A protective wall must be erected around it at least 200mm above the
• If it is partially buried then it must be at least 200mm above the
• If it is placed in an area with limited space then ensure that it has gas
• Two vents, a minimum of 100mm in diameter, open to the atmosphere
• An induct vent, at low or high level directly off the interceptor at the
• An educt vent, at a high level also directly off the interceptor at the
• The educt Vent diverted to at least 2 meters above the highest point of
• Exterior flaps on the openings of the induct and educt vents.
• Inlet compartment• Separation compartment
• Outlet compartment.
e) Certificate of Compliance A certificate of compliance must be provided by the licensed plumbers after
• Remove lid from the top of the interceptor.• Place suction hose into the compartment.• Begin pump out.• Scrape the inside of the compartment to remove FOG that is stuck to
• Continue pump out until all FOG is removed.• DO NOT use degreasers to clean out the grease trap.• DO NOT use hot water to clean out the grease trap as this will only
make the solidified FOG soluble and harder to remove.
5
3
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors 21
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors
20
3
3.3.4 GUIDELINES
3.3.4.1 Underground Grease Interceptor
A. FABRICATION:
a) Total Volume The underground grease interceptor shall have minimum total volume of
1000 litres. Larger interceptors, that have a volume greater than 1000 litres and up
to 5000 litres, can use the dimensions provided in Table 3.2.
b) SizingFor situations where the volume of FOG to be separated exceeds the working capacity of the 1000 litre grease interceptor and is less than that of the 5000 litre grease interceptor:
• A larger sized grease interceptor can be used. For further specifications please refer to the dimensions provided in Table 3.2 to suit the require-ments of the situation
Or• Two or more grease interceptors can be installed in series to cater for the
load.
c) MaterialsThe Interceptor will be made of concrete and be either precast or constructed from the ground up.
Other materials can be used but these must be approved by WAF before it can be manufactured or built.
d) ManufacturingThe first baffle shall extend from the cover above the water level and down to be at least 100mm away from the inside floor of the interceptor and be spaced 250mm away from the inlet.
The second baffle shall extend from the inside floor of the interceptor and up to be at least 200mm away from the cover above and be spaced 300mm away from the outlet.
The vent shall be positioned at opposite sides of the interceptor and be at least 50mm above the water level.(Refer to INSTALLATION part(c) Vents for minimum Vent size)The above mentioned specifications is for the 1000 litre underground grease interceptor. Refer to Table 3.2 for specifications for larger Grease Interceptors.
e) Alternative DesignsAny alternative designs for underground Grease Interceptors that a business wishes to use on their property must first be approved by the WAF.
B. INSTALLATION:a) Positioning of the Underground Grease Interceptor The underground grease interceptor shall be placed as close as practi-
cal to the fixture(s) being served.
It shall be located where it is easily accessible at all times for inspection, clean-ing, and removal of accumulated grease.
It can be installed indoors or outdoors.
In situations where the interceptor is placed outdoors:• Ensure that it is as close as possible to the building.
• Ensure that it can withstand the external loads being placed on it (vehicles and people).
• If it is buried and the top of the interceptor is level with the ground then all piping for vents and inspection points must not disrupt other utility connections, hinder vehicles or people.
• A protective wall must be erected around it at least 200mm above the ground level to prevent water run offs from seeping into the intercep-tor.
• It must be at least 200mm above the ground level to prevent water run offs from seeping into it (if they grease interceptor will not be.
In situations where the interceptor is placed indoors:• Ensure that it can withstand the external loads being placed on it
(vehicles or people).
• A protective wall must be erected around it at least 200mm above the
• If it is partially buried then it must be at least 200mm above the
• If it is placed in an area with limited space then ensure that it has gas
• Two vents, a minimum of 100mm in diameter, open to the atmosphere
• An induct vent, at low or high level directly off the interceptor at the
• An educt vent, at a high level also directly off the interceptor at the
• The educt Vent diverted to at least 2 meters above the highest point of
• Exterior flaps on the openings of the induct and educt vents.
• Inlet compartment• Separation compartment
• Outlet compartment.
e) Certificate of Compliance A certificate of compliance must be provided by the licensed plumbers after
• Remove lid from the top of the interceptor.• Place suction hose into the compartment.• Begin pump out.• Scrape the inside of the compartment to remove FOG that is stuck to
• Continue pump out until all FOG is removed.• DO NOT use degreasers to clean out the grease trap.• DO NOT use hot water to clean out the grease trap as this will only
make the solidified FOG soluble and harder to remove.
5
3
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors 23
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors
22
3
• A larger sized grease interceptor can be used. For further specifications
• Two or more grease interceptors can be installed in series to cater for the
The first baffle shall extend from the cover above the water level and down to be
The second baffle shall extend from the inside floor of the interceptor and up to
The above mentioned specifications is for the 1000 litre underground grease interceptor. Refer to Table 3.2 for specifications for larger Grease Interceptors.
wishes to use on their property must first be approved by the WAF.
cal to the fixture(s) being served.
• Ensure that it is as close as possible to the building.
• Ensure that it can withstand the external loads being placed on it
• If it is buried and the top of the interceptor is level with the ground
• A protective wall must be erected around it at least 200mm above the
• It must be at least 200mm above the ground level to prevent water run
• Ensure that it can withstand the external loads being placed on it
• A protective wall must be erected around it at least 200mm above the ground level to prevent water runoff from seeping into the interceptor (If the top of the interceptor is level with the ground).
• If it is partially buried then it must be at least 200mm above the ground level to prevent water run offs from seeping into its compart-ments.
• If it is placed in an area with limited space then ensure that it has gas tight lids and proper venting.
b) PipingThere shall be no piping inside the underground grease interceptor. All pipe works must be completed by a licensed plumber.
The inlet pipe will be submerged and therefore the water level inside the trap will be determined by the level of the outlet pipe.
The piping will be completed according to the WAF Fabrication & installation of Grease Traps and Underground Grease interceptors’ guidelines.
Inspection points must be included on the inlet pipe before the interceptor and on the outlet pipe after the interceptor
The inspection points must be a minimum of 100mm in diameter and should be teed off from the inlet and outlet pipes to at least 200mm above the ground level.
c) VentingAll Underground Grease Interceptors must have:• Two vents, a minimum of 100mm in diameter, open to the atmosphere
to allow for cross ventilation.• An induct vent, at low or high level directly off the interceptor at the
inlet compartment. • An educt vent, at a high level also directly off the interceptor at the
outlet compartment.• The educt Vent diverted to at least 2 meters above the highest point of
the building (where necessary).• Exterior flaps on the openings of the induct and educt vents.
Plumbers must ensure that the vents are installed properly so that siphoning does not occur within the chambers of the interceptor.
d) Access to the InterceptorAccess to the Grease interceptor shall be though one of three lids above the:• Inlet compartment• Separation compartment and • Outlet compartment.
e) Certificate of Compliance A certificate of compliance must be provided by the licensed plumbers after the installation of the trap.
C. MAINTENANCE:a) Frequency of Clean OutsThe interceptor should be cleaned on a fortnightly basis through pump outs.
Grease interceptors with a volume greater than 1000 litres and less than 3000 litres must be cleaned out at least every month.
If business owner(s) wish to pump out their underground grease interceptors more frequently (such as weekly) they are allowed to do so.
b) Responsibility for Clean outs and DisposalsIt is the responsibility of the Trade Waste Permit Holders to ensure that the clean outs of the Grease traps/interceptors are done on a regular basis and disposed of properly.
It is NOT the responsibility of WAF or the relevant authorities to clean out the traps/interceptors. However, it is WAFs and other authorities’ responsibility to monitor the businesses or residents to ensure that this is done regularly and properly.
c) Clean out Methodsa) Clean out of Underground grease interceptors can be done through pump outs.
• Remove lid from the top of the interceptor.• Place suction hose into the compartment.• Begin pump out.• Scrape the inside of the compartment to remove FOG that is stuck to
• Continue pump out until all FOG is removed.• DO NOT use degreasers to clean out the grease trap.• DO NOT use hot water to clean out the grease trap as this will only
make the solidified FOG soluble and harder to remove.
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors 25
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors
24
• A larger sized grease interceptor can be used. For further specifications
• Two or more grease interceptors can be installed in series to cater for the
The first baffle shall extend from the cover above the water level and down to be
The second baffle shall extend from the inside floor of the interceptor and up to
The above mentioned specifications is for the 1000 litre underground grease interceptor. Refer to Table 3.2 for specifications for larger Grease Interceptors.
wishes to use on their property must first be approved by the WAF.
cal to the fixture(s) being served.
• Ensure that it is as close as possible to the building.
• Ensure that it can withstand the external loads being placed on it
• If it is buried and the top of the interceptor is level with the ground
• A protective wall must be erected around it at least 200mm above the
• It must be at least 200mm above the ground level to prevent water run
• Ensure that it can withstand the external loads being placed on it
• A protective wall must be erected around it at least 200mm above the
• If it is partially buried then it must be at least 200mm above the
• If it is placed in an area with limited space then ensure that it has gas
• Two vents, a minimum of 100mm in diameter, open to the atmosphere
• An induct vent, at low or high level directly off the interceptor at the
• An educt vent, at a high level also directly off the interceptor at the
• The educt Vent diverted to at least 2 meters above the highest point of
• Exterior flaps on the openings of the induct and educt vents.
• Inlet compartment• Separation compartment
• Outlet compartment.
e) Certificate of Compliance A certificate of compliance must be provided by the licensed plumbers after
For Pump outs:• Remove lid from the top of the interceptor.• Place suction hose into the compartment.• Begin pump out.• Scrape the inside of the compartment to remove FOG that is stuck to
its inside surface.• Continue pump out until all FOG is removed.• DO NOT use degreasers to clean out the grease trap.• DO NOT use hot water to clean out the grease trap as this will only
make the solidified FOG soluble and harder to remove.
d) Disposal of FOGFOG that is removed through pump outs can be disposed by the bailing trucks.
4. APPENDICES
4.1 FOG MANAGEMENT
CHECKLIST FOR MANAGING FAT, OILS AND GREASE IN THE KITCHEN
DO's DON'Ts
Wipe and scrape plates, pots, pans and utensils before washing it in the sink (place all these food scrapings into the rubbish bin) × Do not pour Cooking Oil, Fat or
Grease down the sinks
Collect Waste Oil in a suitable secure container. ×
Do not pour Waste Oil, Fat or Grease down the drains
Use sink strainers in sink holes and empty solid contents from the strainer into the rubbish bin. ×
Do not put food scrapings into the sink. Put it into the rubbish bin.
Regularly clean out and maintain grease traps. ×
Do not sweep waste into floor drains. Collect and place it in the rubbish bin.
Get a licensed waste management company to collect and dispose of FOG from grease traps ×
Do not pour boiling hot water down the sink to dissolve fat and grease.
• A larger sized grease interceptor can be used. For further specifications
• Two or more grease interceptors can be installed in series to cater for the
The first baffle shall extend from the cover above the water level and down to be
The second baffle shall extend from the inside floor of the interceptor and up to
The above mentioned specifications is for the 1000 litre underground grease interceptor. Refer to Table 3.2 for specifications for larger Grease Interceptors.
wishes to use on their property must first be approved by the WAF.
cal to the fixture(s) being served.
• Ensure that it is as close as possible to the building.
• Ensure that it can withstand the external loads being placed on it
• If it is buried and the top of the interceptor is level with the ground
• A protective wall must be erected around it at least 200mm above the
• It must be at least 200mm above the ground level to prevent water run
• Ensure that it can withstand the external loads being placed on it
• A protective wall must be erected around it at least 200mm above the
• If it is partially buried then it must be at least 200mm above the
• If it is placed in an area with limited space then ensure that it has gas
• Two vents, a minimum of 100mm in diameter, open to the atmosphere
• An induct vent, at low or high level directly off the interceptor at the
• An educt vent, at a high level also directly off the interceptor at the
• The educt Vent diverted to at least 2 meters above the highest point of
• Exterior flaps on the openings of the induct and educt vents.
• Inlet compartment• Separation compartment
• Outlet compartment.
e) Certificate of Compliance A certificate of compliance must be provided by the licensed plumbers after
• Remove lid from the top of the interceptor.• Place suction hose into the compartment.• Begin pump out.• Scrape the inside of the compartment to remove FOG that is stuck to
• Continue pump out until all FOG is removed.• DO NOT use degreasers to clean out the grease trap.• DO NOT use hot water to clean out the grease trap as this will only
make the solidified FOG soluble and harder to remove.
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors 27
Water Authority of Fiji | Fabrication & Installation of Grease Traps and Underground Grease Interceptors
26
4.2 MINIMUM PRETREATMENT REQUIREMENTS FOR FOOD PROCESSES
Commercial process
Seats/bed
s
Minimum pre- treatment
in floor and in sink bucket traps
Supermarket with chicken cooker
1500 L yes
BBQ wholesale (chicken) 1500 L yes
BBQ wholesale (pork, duck)
2000 L yes
BBQ restaurant 2000 L yes
Hotel/motel kitchen 1-69 1000 L yes
Hotel/motel kitchen 70-199 1500 L yes
Hotel/motel kitchen 200-399 2000 L yes
Hotel/motel kitchen 400-599 3000 L yes
Hotel/motel kitchen 600-799 4000 L yes
Hotel/motel kitchen 800-1000 5000 L yes
Butchers – retail (no cooking)
1000 L yes
Fish (fresh outlet) no cooking
Large basket trap with fixed screen and removable basket
yes
Chicken (fresh retail) no cooking
1000 L yes
Bakery retail –hot bread - cakes
No grease trap yes
Bakery retail – pies – sausage rolls
1000 L
Commercial process Seats/beds
Minimum pre-treatment
in floor and in sink bucket traps
Cafeteria, canteen (and school hot meals)
1000 L yes
Take-away, including food court shops
1000 L yes
Snack bar – coffee lounge Under sink yes
Restaurant
1-69
1000 L
yes
Restaurant
70-199
1500 L
yes
Restaurant
200-399
2000 L
yes
Restaurant
400-599
3000 L
yes
Restaurant
600-799
4000 L
yes
Restaurant 800-1000 5000 L yes
Kitchen – hospital, nursing home
1-69
1000 L
yes
Kitchen – hospital, nursing home
70-199
1500 L
yes
Kitchen – hospital, nursing home
200-399
2000 L
yes
Kitchen – hospital, nursing home
400-599
3000 L
yes
Kitchen – hospital, nursing home
600-799
4000 L
yes
Kitchen – hospital, nursing home
800-1000
5000 L
yes
McDonalds
1500 L – 3000 L
yes
Pizza Hut Restaurant 1000 L yes
Function centre
1-69
1000 L
yes
Function centre
70-199
1500 L
yes
Function centre
200-399
2000 L
yes
Function centre
400-599
3000 L
yes
Function centre
600-799
4000 L
yes
Function centre
800-1000
5000 L
yes
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