§939. Additional Provisions
A. Additional provisions for vents are contained in Chapter 13, Medical Facilities Plumbing Systems of this code.
AUTHORITY NOTE: Promulgated in accordance with R.S. 40:4(A)(7) and R.S. 40:5(2)(3)(7)(9)(16)(17)(20).
HISTORICAL NOTE: Promulgated by the Department of Health and Hospitals, Office of Public Health, LR 38:2867 (November 2012).
§941. Additional Information
A. Additional information for vents is contained in Chapter 18 (Appendices) and §1807 (Appendix C, Illustrations) of this code. Such additional information in Chapter 18 of this code shall not be construed as superceding any pertinent regulation(s) contained in LAC Chapters 1-17 of this code.
AUTHORITY NOTE: Promulgated in accordance with R.S. 40:4(A)(7) and R.S. 40:5(2)(3)(7)(9)(16)(17)(20).
HISTORICAL NOTE: Promulgated by the Department of Health and Hospitals, Office of Public Health, LR 38:2867 (November 2012).
Chapter 10. Traps
§1001. General
A. Scope. The provisions of this Chapter shall govern the materials and installation of traps.
B. Trap Seal. Each fixture trap shall have a water seal of not less than 2 inches (51 mm) and not more than 4 inches (102 mm), except where a deeper seal is required by the plumbing official for special conditions.
C. Trap Level and Protection. Traps shall be set level with respect to their water seals.
D. Traps Underground. Underground traps, except "P" traps into which floor drains with removable strainers discharge, shall be provided with accessible and removable cleanouts.
E. Prohibited Traps. The following traps (or types of traps) are prohibited from use:
1. a trap which depends for its seal upon the action of movable parts;
2. "S" traps;
a. Exception. Water closets, clinical sinks, urinals and similar fixtures shall be allowed to be "S" trapped if the fixture has an integral trap which is automatically and properly refilled using an approved device.
3. bell traps;
4. crown-vented traps (see §913.D of this code);
5. baffled or partition traps other than stainless steel, glass, plastic or similar corrosion resistant materials;
6. tubular metallic traps of less than 20 gage [0.0320 inch (0.813 mm)] thickness; and,
7. running traps.
a. Exceptions
i. A running trap with cleanout may be allowed on condensate waste lines (see §1305.I of this code).
ii. A running trap may be authorized for certain floor level fixtures installed on a Combination Waste and Vent System when plans and specifications have been specially approved by the state health officer under the requirements of Chapter 12 (Alternate Designed Plumbing Systems) of this code. See guidance for same under §1811.C.4 of this code.
F. Double Trapping. A fixture shall not be double trapped.
1. Exception. Fixtures in mobile/manufactured homes and travel trailers are allowed to be double trapped when a trailer trap is required to be placed in the building sewer/sewer lateral as per §1003.E, §1515.J, §1523.A, §1613.J or §1623.A of this code.
G. Unions (Threaded). Unions may be used in the trap seal and on the inlet side of the trap. Unions shall have metal-to-metal seats.
H. Fixture Trap Required, Location, and Number of Traps Per Fixture. The requirement for a fixture trap and the number of traps per fixture shall be in conformance with the following.
1. Plumbing fixtures, excepting those having integral traps, shall be separately trapped by a water seal trap, placed as close to the fixture outlet as possible.
2. A combination plumbing fixture may be installed on one trap, if one compartment is not more than 6 inches (152 mm) deeper than the other and the waste outlets are not more than 30 inches (762 mm) apart.
3. One trap may be installed for a set of not more than three single-compartment sinks or laundry trays or three lavatories immediately adjacent to each other in the same room, if the waste outlets are not more than 30 inches (762 mm) apart and the trap is centrally located when three compartments are installed.
I. Distance of Trap Weir from Fixture Outlet. The vertical distance from the fixture outlet to the trap weir, or from the outlet of an integrally trapped water closet or similar fixture to the horizontal piping connecting the fixture to its vent, shall not exceed 24 inches (610 mm).
1. Exception. Washing Machine Pumped Waste Drain. The vertical distance from the vertical standpipe inlet receiving the pumped waste discharge from a washing machine (laundry) to the trap weir shall be a minimum of 30 inches (762 mm) and a maximum of 48 inches (1219 mm), with the vertical standpipe inlet terminating a minimum of 34 inches (864 mm) above finished floor or in accordance with the manufacturer's recommendation.
AUTHORITY NOTE: Promulgated in accordance with R.S. 40:4(A)(7) and R.S. 40:5(2)(3)(7)(9)(16)(17)(20).
HISTORICAL NOTE: Promulgated by the Department of Health and Hospitals, Office of Public Health, LR 38:2867 (November 2012).
§1003. Type and Size of Traps and Fixture Drains
A. Trap Size. The size (nominal diameter) of a trap for a given fixture shall be sufficient to drain the fixture rapidly but in no case less than given in Table 723.A of this code.
B. Relation to Fixture Drains. A trap shall not be larger than the fixture drain to which it is connected.
C. Type of Traps. Traps shall conform with the following requirements.
1. Fixture traps shall be self-cleaning, other than integral traps and drum traps, without partitions or movable parts, except as specifically approved in other Sections of this Chapter.
2. Slip joints may be used on both sides of the trap and in the trap seal.
3. A trap which is integral with the fixture shall have a uniform interior and a smooth waterway.
D. Drum Traps. The use of drum traps shall comply with the following requirements:
1. Drum traps shall be limited to special fixtures wherein the capture of solids (e.g., broken teeth, fillings, etc., from dental cuspidors) is desired so that such solids can be removed before they escape into the downstream drainage system. Drum traps are subject to approval by the plumbing official. The body of the drum trap shall be not less than 4-inch diameter and shall have a water seal of not less than 2 inches (51 mm).
2. The trap screw of the drum trap/drum trap cover shall be one size less than the body of the drum trap's diameter.
E. Trailer Traps. Mobile/manufactured homes and travel trailers shall be provided with a trailer trap in the building sewer/sewer lateral immediately downstream of the mobile/manufactured home or travel trailer drain outlet connection. The trailer trap shall be individually vented and the vent shall be located downstream of the trap at a distance in accord with Table 913.A, Section 913.D and Section 1001.E.4 of this code. Running traps are prohibited for this installation. See diagram under §1523.A or §1623.A of this code.
1. Exception. The trailer trap for a mobile/manufactured home or travel trailer is not required to be provided with an individual vent if the mobile/manufactured home or travel trailer is connected to a park drainage system constructed in accord with §1613.G or §1515.G of this code and the building sewer/sewer lateral is no longer than 30 feet (9144 mm) from the main park drainage sewer main. For this individual vent exception to apply, the building sewer/sewer lateral shall enter the main park drainage sewer main on the horizontal such that an "S" trap or an effective "S" trap is not created. See §§1515.J and 1613.E.1 of this code.
Figure 1003.ETrailer Trap and Vent
AUTHORITY NOTE: Promulgated in accordance with R.S. 40:4(A)(7) and R.S. 40:5(2)(3)(7)(9)(16)(17)(20).
HISTORICAL NOTE: Promulgated by the Department of Health and Hospitals, Office of Public Health, LR 38:2868 (November 2012).
§1005. Interceptors and Separators
A. When required. Interceptors or separators shall be provided for the proper handling of liquid wastes containing grease, oil, flammable waste, sand, solids or other ingredients harmful to the building drainage system, the sewerage system or sewage treatment plant or processes except when, in the opinion of the plumbing official, they are not necessary.
B. Size and Type. The size, type and location of each interceptor or separator shall be approved by the plumbing official.
C. Type of Waste. No wastes other than those requiring treatment or separation shall be discharged into any interceptor or separator except where otherwise specifically permitted.
D. Grease Traps, Grease Interceptors, and Large Capacity Grease Interceptors. An approved type grease trap, grease interceptor, or large capacity grease interceptor complying with the provisions of this Section shall be installed in the waste line leading from sinks, drains and other fixtures or equipment in establishments such as restaurants, cafes, lunch counters, cafeterias, bars and clubs, hotels, hospitals, sanitariums, factory, school or day care center kitchens, markets, or other establishments where grease may be introduced into the drainage or sewage system in quantities that can affect line stoppage or hinder sewage treatment or the functioning of an individual sewerage system, except when, in the opinion of the plumbing official, they are not necessary.
E. Oil Separators. An oil separator shall be installed in the drainage system section of the system where, in the opinion of the plumbing official, a hazard exists or where oils or other flammables can be introduced or admitted into the drainage system by accident or otherwise.
F. Sand Interceptors. Sand and similar interceptors for heavy solids shall have a water seal of not less than 2 inches (51 mm).
G. Venting Interceptors. Interceptors shall be so designed that they will not become air bound if closed covers are used. Each interceptor shall be properly vented.
H. Accessibility of Interceptors. Each interceptor shall be so installed as to provide ready accessibility to the cover and means for servicing and maintaining the interceptor in working and operating condition. The use of ladders or the removal of bulky equipment in order to service interceptors shall constitute a violation of accessibility.
I. Water Connection. If permitted by the plumbing official, any water connection for cooling or operating an interceptor shall be such that backflow cannot occur.
J. Special Occupancy Provisions. Laundries, bottling plants and slaughter houses shall be provided with an interceptor or separator in conformance with the following.
1. Laundries. Laundries shall be provided with an interceptor as follows.
a. Interceptor. Commercial laundries shall be equipped with an interceptor having a removable wire basket or similar device that will prevent strings, rags, buttons, or other materials detrimental to the sewerage system from passing into the drainage system.
b. Intercepting Basket/Device. The basket or other device shall prevent passage into the drainage system of solids 1/2-inch (12.7 mm) or larger in size. The basket or device shall be removable for cleaning purposes.
2. Bottling Plants. Bottling plants shall discharge their process wastes into an interceptor which will provide for the separation of broken glass or other solids, before discharging liquid wastes into the drainage system.
3. Slaughter House Drains. Slaughtering room drains shall be equipped with separators which shall prevent the discharge into the drainage system of feathers, entrails and other materials likely to clog the drainage system.
K. Food Service. The following special requirements apply to the handling of organic wastes of food origin.
1. Commercial Food-Waste Grinders. Where commercial food-waste grinders are installed, the waste from those units shall discharge through a grease trap of an approved design for this use.
2. Wash Racks. Every wash rack and/or floor or slab used for cleaning containers and equipment exposed to organic wastes of food origin shall be adequately protected against storm or surface water and shall drain or discharge into a grease trap of an approved design for this use.
L. Maintenance. Grease traps, grease interceptors, large capacity grease interceptors, and other types of interceptors and separators shall be maintained in conformance with the following.
1. Grease Traps and Grease Interceptors. Grease traps, grease interceptors, and large capacity grease interceptors shall be maintained in efficient operating condition by periodic removal of the accumulated grease. No such collected grease shall be introduced into any drainage piping or sewerage system.
2. Interceptors and Separators in General. Interceptors and separators of all types shall be maintained in efficient operating condition by periodic removal of accumulated material for which the interceptor or separator has been designed. No such collected material shall be introduced into any drainage piping or sewerage system.
M. Special Type Interceptors/Separators. The plumbing official may require the submittal of drawings and other pertinent information for any interceptor/separator designed for a special or unusual purpose/use.
N. Procedures for Design, Construction and Installation of Interceptors and Separators [formerly Appendix M - Procedures for Design, Construction and Installation of Interceptors and Separators]. The provisions of this Subsection shall apply to the design, construction, installation and testing of interceptors and separators required in accordance with Subsections A - M of §1005 of this code.
1. Definitions. Definitions contained in Chapter 2 of this code shall also apply to this Section except where the following special definitions shall apply.
Bottling Plant Separator—an interceptor designed to separate and retain broken glass and other solids.
Grease Interceptor—an interceptor of less than 125 gallon capacity which is designed and installed so as to separate and retain grease. Typically identified by flow rate and/or grease capacity and generally installed indoors adjacent to the plumbing fixtures they serve. (See §1005.N.6 of this code for design and sizing requirements.)
Grease Trap—an interceptor of at least 125 gallon capacity which is designed and installed to separate and retain grease. Typically identified by liquid holding capacity (volume) and generally installed below grade(G) outdoors with provisions for above grade(G) accessibility for cleaning purposes. (See §1005.N.3 of this code for sizing requirements and §1005.N.4 of this code for design requirements.)
Large Capacity Grease Interceptor—an interceptor of at least 125 gallon capacity conforming to ASME A 112.14.3 or PDI-G101 which is designed and installed to separate and retain grease. Generally manufactured to be installed above or below grade(G) either indoors or outdoors. (See §1005.N.3 of this code for sizing requirements and §1005.N.5 of this code for design requirements.)
Laundry Trap—an interceptor designed to separate and retain lint, strings, rags, buttons or other similar materials which may be discharged from laundries.
Oil Separator—an interceptor designed to separate and retain waste oil and other petroleum products.
Sand Interceptor—an interceptor designed to separate and retain sand, gritty material or other types of heavy solids.
Slaughter House Separator—an interceptor designed to separate and retain feathers, entrails and other similar substances.
Special Type Separator—an interceptor designed to separate and retain deleterious, hazardous or undesirable matter from normal wastes for proper disposal, rendering, or recycling.
2. General Regulations. The following general regulations are applicable to interceptors and separators.
a. Size and Type. The size and type of each interceptor or separator shall be in accordance with the requirements of this Section and shall be approved by the plumbing official.
b. Location. The location of each interceptor or separator shall be approved by the plumbing official.
c. Prior Approval. No interceptor or separator shall be installed until its design, size, location and venting has been approved by the plumbing official.
d. Cleanout on Discharge Line. A two-way cleanout shall be provided on the discharge line immediately downstream of all interceptors.
e. Grease Traps/Grease Interceptors/Large Capacity Grease Interceptors. When it has been determined under §1005.D of this code that a trap or interceptor is required, the following regulations apply to the use of a grease trap or large capacity grease interceptor versus the allowance of the use of a grease interceptor.
i. A grease trap or large capacity grease interceptor shall be required in all instances of new construction or substantial renovation of buildings or facilities. In addition, a grease trap or large capacity grease interceptor shall be required for existing buildings or facilities when a proper installation can be performed without the need to break up a concrete slab.
ii. At the discretion of the plumbing official, a grease interceptor may be allowed in lieu of a grease trap or large capacity grease interceptor when the conditions for a grease trap/large capacity grease interceptor installation do not exist or cannot easily be met. For example, when:
(a). new construction, substantial renovation of buildings or facilities is not being performed and a concrete slab would have to be broken at the existing building or facility for the proper installation of a grease trap;
(b). an outside, unpaved area surrounding the building where a grease trap could be installed is available; however, it is determined that the area is too far away from the plumbing fixtures that the grease trap would be servicing; or,
(c). the installation of a grease trap is unfeasible such as when servicing a kitchen which is located on the upper floors of a multistoried building.
3. Minimum Capacity of Grease Traps and Large Capacity Grease Interceptors. The minimum required capacity of grease traps and large capacity grease interceptors shall be determined based upon the maximum number of persons served during the largest meal period in accordance with the following:
a. General. Grease traps and large capacity grease interceptors should be designed to be large enough to allow the water contained within it to remain cold since only cold water separates grease. In addition, grease traps and large capacity grease interceptors should be designed to be large enough so that they require cleaning at a frequency no more often than once per month.
b. Without Garbage Grinder. The minimum capacity for applications without a garbage grinder shall not be less than 125 gallons below the static water level. This capacity is sufficient to hold the flow from one meal long enough to accomplish proper grease separation when serving up to 50 people during a single meal period. When over 50 people are served during a single meal period, the minimum capacity of the grease trap or large capacity grease interceptor shall be increased beyond 125 gallons based upon at least an additional 2 1/2 gallons per person beginning with the 511st person served and greater.
c. With Garbage Grinder. When a garbage grinder is connected (see §1005.K.1 of this code), the grease trap or large capacity grease interceptor shall have a minimum capacity of no less than 500 gallons below the static water level. This capacity is sufficient to hold the flow from one meal long enough to accomplish proper grease separation when serving up to 50 people during a single meal period. When a garbage grinder is connected and over 50 people are served during a single meal period, the minimum grease trap capacity shall be increased beyond 500 gallons based upon at least an additional 2 1/2 gallons per person beginning with the 51st person served and greater.
d. Alternate Sizing Methods. For informational purposes only, alternate sizing methods may be found in Figures 9, 10, and 11 in Section 1807 of this code.
4. Grease Traps. The following regulations are applicable to the design and installation of grease traps.
a. The minimum required capacity of grease traps shall be determined based upon the maximum number of persons served during the largest meal period in accordance with §1005.N.3 of this code.
b. If a grease trap must be installed within an enclosed building, any access covers shall be gasketed to prevent the intrusion of odors into the building.
c. A one compartment grease trap is acceptable; however, a two compartment, or a one compartment grease trap with a baffle wall between the inlet and outlet, is preferred.
d. The grease trap shall be placed as close to the plumbing fixture(s) discharging greasy waste as possible, but preferably on the outside of the building when feasible.
e. The minimum diameter of the outlet pipe shall not be less than 4 inches.
f. A minimum of one foot of air space shall be provided above the static water level.
g. Venting. The following regulations are applicable to the venting of grease traps:
i. The grease trap outlet shall be properly vented to prevent the trap from siphoning itself out. Any internally vented outlet line shall have the vent terminal extended to within 2 inches of the bottom of the access cover to prevent grease from escaping the grease trap through the open vent terminal.
ii. For those grease traps having a gasketed cover, the grease trap outlet line shall not be allowed to be internally vented. In this case, the outlet line itself shall have a 2-inch vent pipe properly installed.
h. The invert of the grease trap outlet opening, at the point where water exits the grease trap, shall be located at a maximum of 6 inches and a minimum of 4 inches from the floor of the grease trap. This requirement also applies to any intermediate outlets in multi-compartment grease traps. The invert of the inlet shall be at least 3 inches above the invert of the outlet.
i. On unbaffled single compartment grease traps, a 90° ell shall be used on the inlet and shall terminate 6 inches below the static water level. On baffled single compartment grease traps, a baffle wall shall be placed between the inlet and outlet. The inlet shall discharge into the grease trap at a level at least 6 inches below the top of the baffle wall. The baffle wall shall extend from 2 inches below the static water level to the bottom of the grease trap such that incoming water will have to overflow above the top of the baffle wall in order to reach the outlet.
j. The horizontal distance between the inlet and outlet piping in the grease trap should be sufficient to allow gravity-differential separation to the grease so that it will not escape through the outlet. The minimum horizontal distance shall be 24 inches.
k. Access/Covers. The following regulations are applicable to the access to and the covers for grease traps:
i. Access from the top of the grease trap shall be provided by an easily removable cover above an access opening of at least 20 inches square or 24 inches round. Additional access opening/covers shall be provided as necessary to provide accessibility to each compartment in multi-compartment or multi-baffled arrangements as well as access to both the inlet and outlet. Access opening covers shall be above or at grade(G) to provide ready accessibility.
ii. Each access cover shall be designed so that it cannot slide, rotate, or flip when properly installed in order that the opening is not unintentionally exposed. (The intention is that a child-resistant cover be provided. Especially for lightweight covers, mechanical fasteners are recommended to augment the safety of and ensure positive closure of the cover.)
l. No water jacketed grease trap shall be approved or installed.
m. Each grease trap shall have an approved water seal of not less than 2 inches in depth or the diameter of its outlet, whichever is greater.
n. Abandoned grease traps shall be pumped and filled as required for abandoned septic tanks in accord with LAC 51:XIII.715.V.
Figure 1005.N.4A (1 of 2)Grease Trap (top view)
Figure 1005.N.4A (2 of 2)Grease Trap (side view)
Figure 1005.N.4BGrease Trap (sanitary details only)
Figure 1005.N.4CGrease Trap
5. Large Capacity Grease Interceptors. The following design regulations are applicable to large capacity grease interceptors.
a. Large capacity grease interceptors shall be evaluated, tested, and certified for conformance with ASME A 112.14.3 or PDI-G101.
b. The minimum required capacity of large capacity grease interceptors shall be determined based upon the maximum number of persons served during the largest meal period in accordance with §1005.N.3 of this code.
c. Grease interceptors shall be maintained in efficient operating condition by periodic removal of the accumulated grease. No such collected grease shall be introduced into any drainage piping or sewerage system.
d. Each grease interceptor shall have an approved water seal of not less than 2 inches in depth or the diameter of its outlet, whichever is greater. The grease interceptor outlet shall be properly vented to prevent the trap from siphoning itself out.
6. Grease Interceptors. The following design regulations are applicable to grease interceptors:
a. When specially allowed by the plumbing official pursuant to §1005.N.2.e of this code, an approved type grease interceptor complying with ASME A 112.14.3 or PDI-G101 and the provisions of this Paragraph may be installed in the waste line leading from sinks, drains and other fixtures or equipment in establishments such as restaurants, cafes, lunch counters, cafeterias, bars and clubs, hotels, hospitals, sanitariums, factory, school or day care center kitchens, markets, or other establishments where grease may be introduced into the drainage or sewage system in quantities that can affect line stoppage or hinder sewage treatment or the functioning of an individual sewerage system, except when, in the opinion of the plumbing official, they are not necessary.
b. The minimum required size of grease interceptors shall be determined based upon fixture discharge rate (gpm) and grease retention capacity (pounds) in accordance with Figure 1005.N.6 of this code (see also §1005.N.6.h of this code); however, in no case shall a grease interceptor be installed which has an approved rate of flow of less than 20 gallons per minute, except when specially approved by the plumbing official.
c. Each plumbing fixture or piece of equipment connected to a grease interceptor shall be provided with an approved type flow control or restricting device installed in a readily accessible and visible location in the tailpiece or drain outlet of each such fixture. Flow control devices shall be so designed that the flow through such device or devices shall at no time be greater than the rated capacity of the grease interceptors. No flow control device having adjustable or removable parts shall be approved.
d. Each grease interceptor that is rated shall be stamped or labeled by the manufacturer with an indication of its full discharge rate in gallons per minute (gpm). Each grease interceptor allowed to be installed under the provisions of this Paragraph shall have an approved rate of flow which is not less than that given in Table 1005.N.6 of this code based upon the total flow expected in gpm from the total number of connected fixtures (i.e., each grease interceptor shall be rated equal to or greater than the incoming flow). The total capacity, in gallons, from all fixtures discharging into any such grease interceptor shall not exceed two and one-half (2-1/2) times the certified gallon per minute (gpm) flow rate of the grease interceptor as per Table 1005.N.6 of this code.
i. Any grease interceptor installed with the inlet more than 4 feet lower in elevation than the outlet of any fixture discharging into such grease interceptor shall have an approved rate of flow which is not less than 50 percent greater than that given in Table 1005.N.6 of this code.
ii. For the purpose of this Paragraph, the term "fixture" shall mean and include each plumbing fixture, appliance, apparatus or other equipment required to be connected to or discharge into a grease interceptor by any provision of this Paragraph.
e. Each fixture discharging into a grease interceptor shall be trapped and vented in an approved manner. An approved type grease interceptor may be used as a fixture trap for a single fixture when the horizontal distance between the fixture outlet and the grease interceptor does not exceed 4 feet and the vertical tailpipe or drain does not exceed 2 1/2 feet.
f. Grease interceptors shall be maintained in efficient operating condition by periodic removal of the accumulated grease. No such collected grease shall be introduced into any drainage piping or sewerage system.
g. Each grease interceptor shall have an approved water seal of not less than 2 inches in depth or the diameter of its outlet, whichever is greater. The grease interceptor outlet shall be properly vented to prevent the trap from siphoning itself out.
h. When grease interceptors are allowed to be installed by the plumbing official in commercial kitchens, the recommended sizing criteria is provided in Table 1005.N.6 of this code below.
Table 1005.N.6
Grease Interceptors
|
Required Rate of Flow
Per Minute, Gallons
|
Grease Retention Capacity, Pounds
|
20
|
40
|
25
|
50
|
35
|
70
|
50
|
100
|
Procedure for Sizing Grease Interceptors
|
Steps
|
Formula
|
Example
|
1
|
Determine cubic content of fixture by multiplying length x width x depth.
|
A sink 48” long by 24” wide by 12” deep.
Cubic content
48 x 24 x 12 = 13,824 cubic inches
|
2
|
Determine capacity in gallons. 1 gal = 231 cubic inches
|
Contents in gallons
13,824 ÷ 231 = 59.8 gallons
|
3
|
Determine actual drainage load. The fixture is normally filled to about 75 percent of capacity with water. The items being washed displace about 25 percent of the fixture content, thus actual drainage load = 75 percent of fixture capacity.
|
Actual Drainage Load
0.75 x 59.8 = 44.9 gallons
|
4
|
Determine flow rate and drainage period. In general, good practices dictate a 1-minute drainage period; however, where conditions permit, a 2-minute drainage period is acceptable. Drainage period is the actual time required to completely drain the fixture.
Flow rate = Actual Drainage Load ÷ Drainage Period
|
Calculate flow rate for 1-minute period
44.9 ÷ 1 = 44.9 gpm Flow rate
Two-minute period
44.9 ÷ 2 = 22.5 gpm Flow Rate
|
5
|
Select interceptor which corresponds to the flow rate calculated. Note: Select next larger size when flow rate falls between two sizes listed.
|
For 1-minute period, 44.9 gpm requires PDI size “50”.
For 2-minute period, 22.5 gpm requires PDI size “25”.
|
Figure 1005.N.6
7. Oil Separators. The following regulations are applicable to oil separators.
a. All repair garages and gasoline stations with grease racks or grease pits, and all factories which have oily wastes as a result of manufacturing, storage, maintenance, repair, or testing processes shall be provided with an oil separator which shall be connected to all necessary floor drains. The separation of the vapor compartment shall be independently vented to the outer air. If two or more separation or vapor compartments are used, each shall be vented to the outer air or may connect to a header which is installed at a minimum of 6 inches above the spill line of the lowest floor drain and vented independently to the outer air. The minimum size of a flammable vapor vent shall not be less than 2 inches, and when vented through a sidewall, the vent shall not be less than 10 feet above the adjacent level at an approved location. The interceptor shall be vented on the sewer side and this vent shall not connect to a flammable vapor vent. All oil interceptors shall be provided with gastight cleanout covers which shall be readily accessible. The waste line shall not be less than 3 inches in diameter with a full-size two-way cleanout brought to grade(G). When an interceptor is provided with an overflow, it shall be provided with an overflow line (not less than 2 inches in diameter) to an approved waste oil tank having a minimum capacity of 550 gallons and meeting the requirements of the appropriate authority. The waste oil from the separator shall flow by gravity or shall be pumped to a higher elevation by an automatic pump. Pumps shall be adequately sized and accessible. Waste oil tanks shall have a 2-inch minimum pumpout connection at grade(G) and a 1 1/2-inch minimum vent to atmosphere at an approved location at least 10 feet above grade(G).
b. Each manufactured oil interceptor that is rated shall be stamped or labeled by the manufacturer with an indication of its full discharge rate in gallons per minute (gpm). The full discharge rate to such an oil interceptor shall be determined at full flow. Each oil interceptor shall be rated equal to or greater than the incoming flow and shall be provided with an overflow line to an underground tank.
i. Oil interceptors not rated by the manufacturer shall have a depth of not less than 2 feet below the invert of the discharge drain. The outlet opening shall have not less than an 18-inch water seal and shall have a minimum capacity as follows:
(a). where not more than three motor vehicles are serviced and/or stored, oil interceptors shall have a minimum capacity of 6 cubic feet, and 1 cubic foot of capacity shall be added for each vehicle up to 10 vehicles; and
(b). above 10 vehicles, the plumbing official shall determine the size of the oil interceptor required. Where vehicles are serviced only and not stored, oil interceptor capacity shall be based on a net capacity of 1 cubic foot for each 100 square feet of surface to be drained into the oil interceptor, with a minimum of 6 cubic feet.
c. A combination oil and sand interceptor may be installed when the design is approved in writing by the plumbing official.
Figure 1005.N.7AOil Separator
Figure 1005.N.7BOil Separator Details
8. Sand Interceptors. The following regulations are applicable to sand interceptors.
a. Multiple floor drains may discharge into one sand interceptor.
b. Sand interceptors shall be built of brick or concrete, prefabricated coated steel, or other watertight material. The sand interceptor shall have an interior baffle for full separation of the interceptor into two sections. The outlet pipe shall be the same size as the inlet, the minimum
being 3 inches, and the baffle shall have two openings of the same diameter as the outlet pipe and at the same invert as the outlet pipe. These openings shall be staggered so that there cannot be a straight line flow between any inlet pipe and the outlet pipe. The invert of the inlet pipe shall be no lower than the invert of the outlet pipe.
i. The sand interceptor shall have a minimum dimension of 2-feet square for the net free opening of the inlet screen and a minimum depth under the invert of the outlet pipe of 24 inches.
ii. For each 5 gallons per minute flow or fraction thereof over 20 gallons per minute, the area of the sand interceptor inlet section is to be increased by 1 square foot. The outlet section shall at all times have a minimum area of 50 percent of the inlet sections.
iii. The outlet section shall be covered by a solid removable cover set flush with the finished floor, and the inlet section shall have an open grating set flush with the finished floor and suitable for the traffic in the area in which it is located.
c. Sand and similar interceptors for every solid shall be so designed and located as to be readily accessible for cleaning, shall have a water seal of not less than 6 inches, and shall be vented.
d. Alternate designs for construction or baffling of sand interceptors complying with the intent of this code may be submitted to the plumbing official for approval.
Figure 1005.N.8Sand Interceptor
9. Laundry Traps. Laundry equipment that does not have integral strainers shall discharge into an interceptor having a wire basket or similar device that is removable for cleaning and that will prevent passage into the drainage system of solids 1/2-inch or larger in maximum dimension, such as string, rags, buttons or other solid materials detrimental to the drainage system. The laundry trap (laundry interceptor/lint trap) and its connection to the drainage system shall conform to the design depicted in Figure 1005.N.9 of this Part. Any modifications of the design shall be approved by the plumbing official. In additions, the size, location and venting of the interceptor shall be approved by the plumbing official.
Figure 1005.N.9Lint Trap (with Non-Corrode Basket)
10. Bottling Separators. Bottling plants shall discharge their process waste water into an interceptor/separator which will provide for the separation of broken glass or other solids before discharging into the drainage system. The design, size, location and venting of the bottling separator shall be approved by the plumbing official.
11. Slaughter House Separators. Slaughtering room drains shall be equipped with separators which shall prevent the discharge into the drainage system of feathers, entrails and other materials likely to clog the drainage system. The design, size, location and venting of the slaughter house separator shall be approved by the plumbing official.
12. Special Type Separators
a. Every fish, fowl and animal slaughter house or establishment and every fish, fowl and meat packing or curing establishment and every soap factory, tallow rendering, fat rendering and hide curing establishment, or any other establishment from which considerable amounts of grease are likely to be discharged into any plumbing system, community sewerage system, commercial treatment facility, or individual sewerage system, shall be connected to and shall drain or discharge into a grease trap meeting the requirements of this Section and approved by the plumbing official for this use.
b. Interceptors or separators for other special type applications shall not be installed until their design, size, location and venting have been approved by the plumbing official.
AUTHORITY NOTE: Promulgated in accordance with R.S. 40:4(A)(7) and R.S. 40:5(2)(3)(7)(9)(16)(17)(20).
HISTORICAL NOTE: Promulgated by the Department of Health and Hospitals, Office of Public Health, LR 38:2869 (November 2012).
Chapter 11. Storm Drainage
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