Piping: joints, support, protection and testing (7.3) (Plumbing

Last updated October 22, 2026

Values this chapter turns on

drainage air test pressure, held 15 min: 35 kPa; drainage air test pressure, held 15 min
potable water test pressure, held 1 h: 1,000 kPa; potable water test pressure, held 1 h
water service to building sewer separation: 2,440 mm; water service to building sewer separation
max hanger spacing for ABS or PVC pipe: 1.2 m; max hanger spacing for ABS or PVC pipe

Section 7.3. covers how pipes are joined, hung, protected and tested. It is a numbers section: hanger spacing, rod sizes, separation distances and test pressures and times. Expect direct lookups and short scenarios such as "how far apart may the hangers be" or "what air pressure for the rough-in test". The syllabus excludes caulked lead joints, wiped joints, cold-caulked joints, thrust restraint and the vitrified clay protection rule.

Joints and connections

Joint type	Key rule
Screwed	ream or file the pipe end to full bore, no pipe-joint cement or paint on internal threads (7.3.2.3.)
Soldered	made to ASTM B828 (7.3.2.4.)
Flared	use a proper flaring tool; not for hard (drawn) copper (7.3.2.5.)
Mechanical	elastomeric couplings held by stainless steel or cast-iron clamps, or within compression or groove-type couplings (7.3.2.6.)

Connection rules in 7.3.3.:

Drilled and tapped joints in sanitary drainage or vent pipe are only allowed where provision has been made for them, such as a trap seal primer connection (OBC Div. B 7.3.3.1.). No bushing may leave a square edge or shoulder inside the pipe.
Extracted tees in type K or L copper water tube need a purpose-made tool, a branch at least one NPS smaller than the run, a stop so the branch does not project into the run, and a brazed joint with filler melting at not below 540°C (OBC Div. B 7.3.3.2.).
Cast-iron soil pipe and galvanized steel pipe may not be welded (7.3.3.3.).
Slip joints are not allowed in a venting system, and in a drainage system only to connect a fixture trap to a fixture drain in an accessible location (OBC Div. B 7.3.3.4.).
Size changes use an increaser or reducer installed so the system can drain completely (7.3.3.5.).
Floor flanges are brass, except that a cast-iron or plastic system may use a flange of the same material. A lead water closet stub must extend at least 75 mm below the floor flange (OBC Div. B 7.3.3.8.).
Types M and DWV copper must not be bent (7.3.3.10.).
An indirect connection ends above the flood level rim of a directly connected fixture to form an air break of at least 25 mm (OBC Div. B 7.3.3.11.).
Underground copper joints are flared, compression or brazed with BCuP alloy, but compression fittings are not allowed underground under a building (7.3.3.12.).

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Support of piping

Pipes must be supported to stay in alignment and carry their own weight and contents, and piping, fixtures and tanks are supported independently of each other (7.3.4.1., 7.3.4.2.). Copper or brass pipe on a hanger of another metal must be separated and electrically insulated to stop galvanic action (7.3.4.3.).

Vertical piping is supported at its base and at the floor of alternate storeys, with supports not more than 7.5 m apart (OBC Div. B 7.3.4.4.).

Horizontal spacing comes from Table 7.3.4.5.. The values a house plumber uses most:

Material	Maximum spacing
ABS or PVC pipe	1.2 m, plus supports at ends of branches and changes of direction
CPVC pipe	1.0 m
PEX pipe, PE-RT tube	0.8 m
Hard copper, NPS 1 or less	2.5 m
Hard copper, over NPS 1	3.0 m
Cast-iron pipe	3.0 m, at or next to each hub or joint

An ABS or PVC trap arm or fixture drain over 1 m long also needs a support as close as possible to the trap.

Hanger rods and straps (OBC Div. B 7.3.4.5.(5)):

Pipe size	Rod diameter	Strap
NPS 2 or less	6 mm	0.6 mm thick, 12 mm wide
NPS 4 or less	8 mm	0.8 mm thick, 18 mm wide
over NPS 4	13 mm	not listed

Underground horizontal pipe needs a firm, continuous base under its whole length, or hangers from a foundation or structural slab that also carry the weight of the fill (7.3.4.6.). A vent pipe above a roof that may be knocked out of line must be braced (7.3.4.7.).

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Protection of piping

Backfill over underground pipe is placed and tamped to 300 mm over the top of the pipe, free of stones, boulders, cinders and frozen earth (OBC Div. B 7.3.5.1.).
A wall must not bear on a pipe passing through or under it (7.3.5.2.).
Protect piping from freezing and mechanical damage (7.3.5.3., 7.3.5.4.).

Water service separation from the building drain, building sewer or septic system (OBC Div. B 7.3.5.6.):

Rule	Value
Normal horizontal separation	2,440 mm of undisturbed or compacted earth
Shared trench option	water pipe bottom at least 500 mm above the sewer top, on a shelf at one side
Other options	water pipe in one run with no joints, or a sewer pressure tested at 345 kPa
Crossing under a sewer	500 mm vertical clearance, support for the sewer, no water pipe joints within 2,440 mm
Within 15 m of a septic system or pollution source	water service must be a single run with no joints

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Testing drainage and venting systems

After rough-in and before fixtures are installed or pipe is covered, run a water or air test (OBC Div. B 7.3.6.1.). A final test is done when the chief building official asks for it. Buried building drains and building sewers also get a ball test.

Test	Requirement
Water test	at least a 3 m water column on all joints, held 15 min (7.3.6.4.)
Air test	35 kPa, held at least 15 min without a drop (7.3.6.5.)
Final test	traps filled, smoke forced in, then 25 mm water column held 15 min (7.3.6.6.)
Ball test	ball at least 50 mm for NPS 3 or more, 25 mm under NPS 3 (7.3.6.7.)

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Testing potable water systems

Test each section before use (7.3.7.1.). The system must hold a water pressure of at least 1,000 kPa for at least 1 h without leakage, or an air pressure of at least 700 kPa for at least 2 h without a drop (OBC Div. B 7.3.7.2.). In a water test, expel all air before closing the fixture valves, and use potable water (7.3.7.3.).

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Worked example

A 9 m straight run of NPS 3 ABS building drain is hung under a basement ceiling. How many hangers does it need at minimum? At 1.2 m maximum spacing, 9 / 1.2 = 7.5 spaces, so 8 spaces are needed, which means 9 support points counting both ends, plus extra supports at any change of direction. The rods may be 8 mm, since the pipe is NPS 4 or less.

Common traps

Mixing the drainage air test (35 kPa, 15 min) with the water system air test (700 kPa, 2 h).
Using the 2.5 m soft copper value for hard copper over NPS 1, which is 3.0 m.
Forgetting that compression fittings are banned only underground under a building, not underground everywhere.

Chapter review

Chapter at a glance

One line per section: the idea to carry into the exam. Then the answers that most often catch candidates out.

Chapter at a glance: the key idea in each section
Section	Key idea
Support of piping	Pipes must be supported to stay in alignment and carry their own weight and contents, and piping, fixtures and tanks are supported independently of each other.
Testing drainage and venting systems	After rough-in and before fixtures are installed or pipe is covered, run a water or air test.

Support of piping
Pipes must be supported to stay in alignment and carry their own weight and contents, and piping, fixtures and tanks are supported independently of each other.
Testing drainage and venting systems
After rough-in and before fixtures are installed or pipe is covered, run a water or air test.

Usual exam traps

Mixing the drainage air test (35 kPa, 15 min) with the water system air test (700 kPa, 2 h).
Using the 2.5 m soft copper value for hard copper over NPS 1, which is 3.0 m.
Forgetting that compression fittings are banned only underground under a building, not underground everywhere.

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Questions on Piping: joints, support, protection and testing (7.3), in the exam format, every answer explained and cited to its article. Sign in to start; a free account gets the free questions.

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Code cited in this chapter

Based on the official 2024 Building Code Compendium on ontario.ca.

OBC Div. B 7.3.2.3. Screwed Joints
(1)In making a screwed joint, the ends of the pipe shall be reamed or filed out to the size of the bore and all chips and cuttings shall be removed.
(2)No pipe-joint cement or paint shall be applied to the internal threads.
Open OBC Div. B 7.3.2.3. in the code viewer
OBC Div. B 7.3.2.4. Solder Joints
(1)Soldered joints shall be made in accordance with ASTM B828, "Standard Specification for Making Capillary Joints by Soldering of Copper and Copper Alloy Tube and Fittings."
Open OBC Div. B 7.3.2.4. in the code viewer
OBC Div. B 7.3.2.5. Flared Joints
(1)In making a flared joint, the pipe shall be expanded with a proper flaring tool.
(2)Flared joints shall not be used for hard (drawn) copper tube.
Open OBC Div. B 7.3.2.5. in the code viewer
OBC Div. B 7.3.2.6. Mechanical Joints
(1)Mechanical joints shall be made with compounded elastomeric couplings or rings that are held in compression by
(a)stainless steel or cast-iron clamps, or
(b)contained within a compression connection or groove- and shoulder-type mechanical couplings. (See Note A-7.3.2.6.(1))
Open OBC Div. B 7.3.2.6. in the code viewer
OBC Div. B 7.3.3.1. Drilled and Tapped Joints
(1)Drilled and tapped joints shall not be made in a sanitary drainage pipe or vent pipe and fittings unless suitable provision has been made for drilling and tapping.
(2)A copper water distributing pipe of NPS 1 or larger may be mechanically swaged to permit the joining of other copper pipe of equal size.
(3)A drainage pipe or fitting may be drilled or tapped
(a)to provide for the connection of a trap seal primer line,
(b)to connect a device designed to dispense germicidal or odour control chemicals or trap seal water to a floor drain downstream of a vacuum breaker or flush valve in a flush tube connected to a sanitary unit,
(c)to provide a hole for a branch connection to a drainage pipe, where the branch connection is made with a saddle hub as permitted by Article 7.2.10.5. and where the hole is drilled to provide a smooth clean hole of the required size and orientation, or
(d)to provide for the connection of pipe or fittings to metal or rigid plastic pipe and fittings where the pipe or fittings are thick enough to be threaded or are bossed for tapping.
(4)No pipe adaption shall be made by the use of a bushing that leaves a square edge or shoulder on the inside of the pipe or fitting.
Open OBC Div. B 7.3.3.1. in the code viewer
OBC Div. B 7.3.3.2. Extracted Tees
(1)Tees may be extracted from the wall thickness of Types K and L copper tube used in a water distribution system, provided that
(a)a tool specifically designed for the purpose is used,
(b)the branch is at least one NPS smaller than the tube in which the tee is formed,
(c)the end of the branch incorporates a means to prevent it from penetrating into the run and thereby obstructing flow, and
(d)the joint at the tee is brazed with a filler metal having a melting point not below 540°C.
Open OBC Div. B 7.3.3.2. in the code viewer
OBC Div. B 7.3.3.3. Prohibition of Welding of Pipes and Fittings
(1)Cast-iron soil pipe and fittings shall not be welded.
(2)Galvanized steel pipe and fittings shall not be welded.
Open OBC Div. B 7.3.3.3. in the code viewer
OBC Div. B 7.3.3.4. Unions and Slip Joints and (3))
(1)Except as provided in Sentence 7.4.6.3.(6), running thread and packing nut connections and unions with a gasket seal shall not be used downstream of a trap weir in a drainage system or in a venting system.
(2)Slip joints shall not be used
(a)in a venting system, or
(b)in a drainage system, except to connect a fixture trap to a fixture drain in an accessible location.
Open OBC Div. B 7.3.3.4. in the code viewer

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OBC Div. B 7.3.3.5. Increaser or Reducer
(1)Connections between 2 pipes of different nominal pipe sizes shall be made with an increaser or a reducer fitting installed so that it permits the system to be completely drained.
Open OBC Div. B 7.3.3.5. in the code viewer
OBC Div. B 7.3.3.8. Connection of Floor or Wall Outlet Fixtures
(1)Pedestal urinals, floor-mounted water closets or S-trap standards shall be connected to a fixture drain by a floor flange or other means of connection, except that a cast-iron trap standard may be caulked to a cast-iron pipe.
(2)Except as provided in Sentence (3), floor flanges shall be brass.
(3)Where cast-iron or plastic pipe is used, a floor flange of the same material is permitted to be used.
(4)Floor flanges and fixtures shall be securely set on a firm base and fastened to the floor or trap flange of the fixture.
(5)Water-closet bowls shall be securely attached to the floor flange, floor or wall carrier.
(6)Joints in a floor flange or between a fixture and the drainage system shall be sealed with a resilient, watertight and gas-tight seal.
(7)Where a lead water-closet stub is used, the length of the stub below the floor flange shall be not less than 75 mm.
Open OBC Div. B 7.3.3.8. in the code viewer
OBC Div. B 7.3.3.10. Copper Tube
(1)Types M and DWV copper tube shall not be bent.
(2)Bends in copper tubing of soft or bending temper shall be made with tools manufactured and sized for the purpose.
Open OBC Div. B 7.3.3.10. in the code viewer
OBC Div. B 7.3.3.11. Indirect Connections
(1)Where a fixture or device is indirectly connected, the connections shall be made by terminating the fixture drain above the flood level rim of a directly connected fixture to form an air break.
(2)The size of the air break shall be not less than 25 mm.
Open OBC Div. B 7.3.3.11. in the code viewer
OBC Div. B 7.3.3.12. Copper Joints Used Underground
(1)Except as provided in Sentence (2), joints in copper tubes installed underground shall be made with either flared or compression fittings, or be brazed using a brazing alloy within the American Welding Society's AWS-BCuP range.
(2)Compression fittings shall not be used underground under a building.
Open OBC Div. B 7.3.3.12. in the code viewer
OBC Div. B 7.3.4.1. Capability of Support
(1)Piping shall be provided with support that is capable of keeping the pipe in alignment and bearing the weight of the pipe and its contents.
(2)Wall mounted fixtures shall be supported so that no strain is transmitted to the piping.
(3)Every floor or wall mounted water closet bowl shall be securely attached to the floor or wall by means of a flange and shall be stable.
Open OBC Div. B 7.3.4.1. in the code viewer
OBC Div. B 7.3.4.2. Independence of Support
(1)Piping, fixtures, tanks or devices shall be supported independently of each other.
Open OBC Div. B 7.3.4.2. in the code viewer
OBC Div. B 7.3.4.3. Insulation of Support
(1)Where a hanger or support for copper tube or brass or copper pipe is of a material other than brass or copper, it shall be suitably separated and electrically insulated from the pipe or tube to prevent galvanic action.
(2)Where a hanger or support for stainless steel pipe or tube is of a material other than stainless steel, it shall be suitably separated and electrically insulated from the pipe or tube.
Open OBC Div. B 7.3.4.3. in the code viewer
OBC Div. B 7.3.4.4. Support for Vertical Piping
(1)Except as provided in Sentence (2), vertical piping shall be supported at its base and at the floor level of alternate storeys by rests, each of which can bear the weight of pipe that is between it and the rest above it.
(2)The maximum spacing of supports shall be 7.5 m.
Open OBC Div. B 7.3.4.4. in the code viewer
OBC Div. B Table 7.3.4.5. Support for Nominally Horizontal Piping
Table 7.3.4.5. — Support for Nominally Horizontal Piping Forming Part of Sentence 7.3.4.5.(2) Piping Material | Maximum Horizontal Spacing of Supports, m | Additional Support Conditions ABS or PVC plastic pipe | 1.2 | At the end of branches or fixture drains and at changes in direction and elevation ABS or PVC plastic trap arm or fixture drain pipe > 1 m long | n/a | As close as possible to the trap Cast-iron pipe | 3.0 | At or adjacent to each hub or joint Cast-iron pipe with mechanical joints that is ≤ 300 mm long between adjacent fittings | 1.0 | None Copper tube or copper and brass pipe, hard temper with diameter > NPS 1 | 3.0 | None Copper tube or copper and brass pipe, hard temper with diameter ≤ NPS 1 | 2.5 | None Copper tube, soft temper | 2.5 | None CPVC pipe | 1.0 | None Galvanized iron or steel pipe with diameter ≥ NPS 6 | 3.75 | None Galvanized iron or steel pipe with diameter < NPS 6 | 2.5 | None Lead pipe | Throughout length of pipe | None PE/AL/PE composite pipe | 1.0 | None PEX/AL/PEX composite pipe | 1.0 | None PEX plastic pipe | 0.8 | None PE-RT tube | 0.8 | None PP-R plastic pipe | 1.0 | At the end of branches and at changes in direction and elevation Stainless steel pipe with diameter ≥ NPS 1 | 3.0 | None Stainless steel pipe with diameter < NPS 1 | 2.5 | None Stainless steel tube with diameter ≥ NPS 1 | 3.0 | None Stainless steel tube with diameter < NPS 1 | 2.5 | None
Open OBC Div. B Table 7.3.4.5. in the code viewer
OBC Div. B 7.3.4.5. Support for Horizontal Piping
(1)Nominally horizontal piping that is inside a building shall be braced to prevent swaying and buckling and to control the effects of thrust.
(2)Nominally horizontal piping shall be supported as stated in Table 2.3.4.5.
(3)Where PVC, CPVC or ABS plastic pipe is installed,
(a)the pipe shall be aligned without added strain on the piping,
(b)the pipe shall not be bent or pulled into position after being welded or joined, and
(c)hangers shall not compress, cut or abrade the pipe.
(4)Where PEX, PE-RT, PP-R, PE/AL/PE or PEX/AL/PEX plastic pipe or tube is installed, hangers shall not compress, cut or abrade the pipe.
(5)Where hangers are used to support nominally horizontal piping, the hangers shall be
(a)supported by metal rods of not less than
(i)6 mm diam to support piping of NPS 2 or less,
(ii)8 mm diam to support piping of NPS 4 or less, and
(iii)13 mm diam to support piping over NPS 4, or
(b)solid or perforated metal straps not less than
(i)0.6 mm thick and 12 mm wide to support piping of NPS 2 or less, and
(ii)0.8 mm thick and 18 mm wide to support piping of NPS 4 or less.
(6)Where a hanger is attached to concrete or masonry, it shall be fastened by metal or expansion-type plugs that are inserted or built into the concrete or masonry.
Open OBC Div. B 7.3.4.5. in the code viewer
OBC Div. B 7.3.4.6. Support for Underground Horizontal Piping
(1)Except as provided in Sentence (2), nominally horizontal piping that is underground shall be supported on a base that is firm and continuous under the whole of the pipe. (See Note A-7.3.4.6.(1))
(2)Nominally horizontal piping installed underground that is not supported as described in Sentence (1) may be installed using hangers fixed to a foundation or structural slab provided that the hangers are capable of
(a)keeping the pipe in alignment, and
(b)supporting the weight of
(i)the pipe,
(ii)its contents, and
(iii)the fill over the pipe.
Open OBC Div. B 7.3.4.6. in the code viewer
OBC Div. B 7.3.4.7. Support for Vent Pipe Above a Roof
(1)Where a vent pipe that may be subject to misalignment terminates above the surface of a roof, it shall be supported or braced. (See Article 7.5.6.5. for location of vent pipe terminals.)
Open OBC Div. B 7.3.4.7. in the code viewer
OBC Div. B 7.3.5.1. Protection of Piping
(1)Where piping is installed underground, the backfill shall be carefully placed and tamped to a height of 300 mm over the top of the pipe and shall be free of stones, boulders, cinders and frozen earth. (See Note A-7.3.5.1.(1))
Open OBC Div. B 7.3.5.1. in the code viewer
OBC Div. B 7.3.5.2. Isolation from Loads
(1)Where piping passes through or under a wall, it shall be installed so that the wall does not bear on the pipe.
Open OBC Div. B 7.3.5.2. in the code viewer
OBC Div. B 7.3.5.3. Protection Against Freezing
(1)Where piping may be exposed to freezing conditions, it shall be protected from the effects of freezing. (See Note A-7.3.5.3.(1))
Open OBC Div. B 7.3.5.3. in the code viewer
OBC Div. B 7.3.5.4. Protection from Mechanical Damage
(1)Plumbing, piping and equipment exposed to mechanical damage shall be protected.
Open OBC Div. B 7.3.5.4. in the code viewer
OBC Div. B 7.3.5.6. Spatial Separation
(1)Except as permitted in Sentences (2) and (3), a buried water service pipe shall be separated from the building drain, building sewer and a private sewage disposal system, by not less than 2,440 mm measured horizontally, of undisturbed or compacted earth.
(2)The water service pipe may be closer than 2,440 mm or be placed in the same trench with the building drain or building sewer if,
(a)the following conditions are met:
(i)the bottom of the water service pipe at all points is at least 500 mm above the top of the building drain or building sewer, and
(ii)when in a common trench with the building drain or building sewer, the water service pipe is placed on a shelf at one side of the common trench,
(b)the water service pipe is constructed of a single run of pipe with no joints or fittings between the street line or source of supply on the property and the inside face of the building, or
(c)the building drain or building sewer is constructed of piping which is pressure tested in accordance with Subsection 7.3.7. at 345 kPa.
(3)A buried water service pipe may pass under a building drain or building sewer if,
(a)a vertical separation of not less than 500 mm is provided between the invert of the building drain or building sewer and the crown of the water service pipe,
(b)adequate structural support is provided for the building drain or building sewer to prevent excessive deflection of joints and settling, and
(c)the length of the water service pipe is located so that there are no joints within 2,440 mm measured horizontally from the intersection with the building drain or building sewer.
(4)A buried water service pipe shall be constructed of a single run of pipe with no joints or fittings between the street line or source of supply on the property and the inside face of the building if the water service pipe is less than 15 m from,
(a)a private sewage disposal system, or
(b)a source of pollution other than a private sewage disposal system.
Open OBC Div. B 7.3.5.6. in the code viewer
OBC Div. B 7.3.6.1. Tests and Inspection of Drainage or Venting Systems
(1)Except in the case of an external leader, after a section of drainage system or a venting system has been roughed in, and before any fixture is installed or piping is covered, a water or an air test shall be conducted.
(2)After every fixture is installed and before any part of the drainage system or venting system is placed in operation, a final test shall be carried out when requested by the chief building official.
(3)Where a prefabricated system is assembled off the building site in such a manner that it cannot be inspected and tested on site, off-site inspections and tests shall be conducted.
(4)Where a prefabricated system is installed as part of a drainage system or venting system, all other plumbing work shall be tested and inspected and a final test shall be carried out on the complete system when requested.
(5)A ball test shall be carried out on a sanitary building drain, sanitary building sewer, storm building drain and a storm building sewer buried underground.
(6)A sewer lateral extension need not be tested and inspected if the sewer lateral extension was constructed, tested and inspected at the time of the installation of the public sewer.
Open OBC Div. B 7.3.6.1. in the code viewer
OBC Div. B 7.3.6.4. Water Pressure Tests
(1)A water pressure test shall consist in applying a water column of at least 3 m to all joints.
(2)In making a water pressure test,
(a)every opening except the highest shall be tightly closed with a testing plug or a screw cap, and
(b)the system or the section shall be kept filled with water for 15 min.
Open OBC Div. B 7.3.6.4. in the code viewer
OBC Div. B 7.3.6.5. Air Pressure Tests
(1)Air pressure tests shall be conducted in accordance with the manufacturer's instructions for the piping materials, and.
(a)air shall be forced into the system until a gauge pressure of 35 kPa is created, and
(b)this pressure shall be maintained for at least 15 min without a drop in pressure. (See Note A-7.3.6.5.(1))
Open OBC Div. B 7.3.6.5. in the code viewer
OBC Div. B 7.3.6.6. Final Tests
(1)Where a final test is made,
(a)every trap shall be filled with water,
(b)the bottom of the system being tested shall terminate at the building trap, test plug or cap,
(c)except as provided in Sentence (2), smoke from smoke-generating machines shall be forced into the system,
(d)when the smoke appears from all roof terminals they shall be closed, and
(e)a pressure equivalent to a 25 mm water column shall be maintained for 15 min without the addition of more smoke.
(2)The smoke referred to in Clauses (1)(c) and (d) is permitted to be omitted provided the roof terminals are closed and the system is subjected to an air pressure equivalent to a 25 mm water column maintained for 15 min without the addition of more air.
Open OBC Div. B 7.3.6.6. in the code viewer
OBC Div. B 7.3.6.7. Ball Tests
(1)Where a ball test is made, a hard ball dense enough not to float shall be rolled through the pipe.
(2)The diameter of the ball shall be not less than
(a)50 mm where the size of the pipe is NPS 3 or more, or
(b)25 mm where the size of the pipe is less than NPS 3.
Open OBC Div. B 7.3.6.7. in the code viewer
OBC Div. B 7.3.7.1. Application of Tests
(1)After a section of a potable water system has been completed, and before it is placed in operation, a water pressure test or an air pressure test shall be conducted.
(2)A pressure test may be applied to each section of the system or to the system as a whole.
(3)Where a prefabricated system is assembled off the building site in such a manner that it cannot be inspected and tested on site, off-site inspections and pressure tests shall be conducted.
(4)Where a prefabricated system is installed as part of a water system,
(a)all other plumbing work shall be tested and inspected, and
(b)the complete system shall be pressure tested when requested.
Open OBC Div. B 7.3.7.1. in the code viewer
OBC Div. B 7.3.7.2. Pressure Tests of Potable Water Systems
(1)Every potable water system shall be capable of
(a)withstanding without leakage a water pressure that is at least 1,000 kPa for at least 1 h, or
(b)withstanding for at least 2 h without a drop in pressure an air pressure that is at least 700 kPa.
Open OBC Div. B 7.3.7.2. in the code viewer
OBC Div. B 7.3.7.3. Water Pressure Tests
(1)Where a water pressure test is made, all air shall be expelled from the system before fixture control valves or faucets are closed.
(2)Potable water shall be used to test a potable water system.
Open OBC Div. B 7.3.7.3. in the code viewer