Journeyman Plumber Practice Exam Kit - 2015 IPC

Only a licensed code officer is empowered to interpret the code. All code decisions are subject to a code officer's interpretation. An appeal can be made if the decision is questionable. Anyone can interpret the plumbing code, but the only decision which counts is the one made by a licensed code officer.

A plumbing permit is not needed for the direct replacement of any plumbing fixture, except for a water heater. However, if a fixture location is changed, a permit is required. In other words, you can remove a toilet and replace it with a new one without the need for a permit. But, if you move the closest flange in any way, a permit is required. This is true for all plumbing fixtures.

Most alterations and repairs to existing plumbing systems are required to comply with current code requirements. There can be some exceptions to this that are available if a variance is applied for and received. An example of this could be when an existing fixture is not vented and current code requires an individual vent for the fixture. You may be able to obtain a variance from a code officer that will allow the installation of a mechanical vent instead of installing a vent pipe where it would be a hardship to do so. Minor alterations to existing plumbing have to be in compliance with current code requirements, but the existing parts of the plumbing system do not have to be changed and brought into compliance with the current code. In no case can any plumbing work cause a plumbing system to become unsafe. Making changes that are detrimental to a plumbing system are never acceptable.

Before a plumbing permit is issued a set of plans and specifications are submitted to the code enforcement office. Once they are approved, a code officer will stamp them as approved and sign them. These become the official plans and specs for a job. This being the case, a copy of the stamped and signed plans and specifications must be kept on the job site at all times for review by a plumbing inspector.

A water heater is one plumbing fixture that requires a permit and an inspection even when it is replaced in the exact location of an existing water heater. Why is this the case? Because water heaters are potential bombs. If a water heater is installed without a proper temperature-and-pressure relief valve, the pressurized vessel (the water heater) can explode due to excessive temperature or pressure.

Minor plumbing repairs do not require the issuance of a permit or an inspection. Plumbers are allowed to fix leaks, replace defective trap arms, replace faucets and similar repairs without any need for a permit. It is even permissible to replace toilets and bathing units in their exact same locations without a permit. Some states do not require a licensed plumber to make such repairs. However, if a fixture location is changed when it is replaced a permit is required.

Plumbing code regulations allow homeowners to obtain plumbing permits for work to be done on their own residences when the homeowners will do the work themselves.

Used plumbing materials can be reused under certain conditions. All materials must be of an approved type. They must be in good working order. A plumbing code officer must approve the use of the specified materials. When these conditions are met it is allowable to reuse previously used plumbing parts and fixtures

Journeyman plumbers are not allowed to apply for plumbing permits. All journeyman plumbers are required to work under the indirect supervision of a master plumber. A master plumber can obtain a plumbing permit. Homeowners who will perform their own plumbing work on their own homes are allowed to obtain permits. However, a homeowner is not allowed to obtain a plumbing permit and then allow some other person to do the plumbing work. Property owners are only allowed to be issued plumbing permits when the property where the work will be performed by the owner is the owner's personal residency. In other words, landlords are not allowed to obtain their own plumbing permits.

Most municipalities prohibit plumbers from working on municipal plumbing parts and systems. This can apply to piping, water meters, pressure-reducing valves, piping, fittings, and other devices. Normal procedure is for a plumber's work to end within a five-foot range of the foundation of a structure. There are exceptions to this rule. Any local jurisdiction can define their own rules on who may service, repair, install or remove municipal plumbing devices.

All permit applications must be accompanied by a full description of the work to be done. Larger jobs, such as plumbing a bathroom addition, a home, or a commercial building require a set of plans to be submitted with a permit application. Specifications are also required for all plumbing permits. The specs must detail all materials to be used in a job. Permit applications require the physical address of the property to receive plumbing services. Normally, the name of the property owner is also required.

Journeyman plumbers are required to work under the indirect supervision of a master plumber. Therefore, journeyman plumbers are not allowed to be self-employed plumbers. However, anyone can own and operate a plumbing business if they have a master plumber employed by the company. So a journeyman plumber could hire a master plumber and open a plumbing business. But without a master plumber, a journeyman cannot operate a full-service plumbing business. Some states do allow journeyman plumbers to work on their own in doing simple repairs and replacements that do not require the issuance of a plumbing permit.

A code officer has latitude in deciding if a permit will be rendered invalid for a lack of work being started within six months of the issuance of a permit. By code, the work must begin within the first six months of the issuance of a permit. This is the rule under both the IPC and UPC. However, you should check with your local jurisdiction, as they have authority to set their own time periods. There are times when weather or other uncontrollable issues prohibit the timely commencement of work. When this is the case a code officer can offer an extension of time for work to be begun.

Any plumbing alteration is expected to comply with current code requirements. At no time can an alteration be detrimental to a plumbing system or render the system unsafe. Some plumbers think that existing plumbing systems are exempt from current code requirements. This is true if the system is in safe operating condition. But, the moment an alteration to the system is made the alteration must be within current code requirements. However, the existing plumbing that is not being altered is not required to be upgraded to current code compliance.

Occasionally work is started on a job and then grinds to a halt. For example, the underground plumbing may be put in and the concrete contractor may delay further plumbing work. Or, the framing contractor may move slowly and prevent the plumbing contractor from moving forward quickly. Through no real fault of the plumber a job can be stalled. If plumbing work is stalled for more than six months the existing plumbing permit can be determined to be invalid. This decision is up to the local plumbing inspector.

Plumbing codes require different minimum standards for various types of building uses. For example, the minimum number of fixtures required for a building can vary substantially based on the use of a building. Accessibility requirements that do not apply to a residence can apply to an office building or business. There are several situations where everything from pipe sizing to the number of fixtures required can be different for various types of building uses. In order to change the use of a building within compliance to code requirements a plan and specifications must be submitted to the code enforcement office for approval.

Anyone may own a plumbing company provided a Master Plumber is employed by that company and has a current Master License. A homeowner is exempt from plumbing license law requirements but may have to obtain a plumbing permit to perform plumbing work on his homestead. Commercial plumbing jobs require at least a Journeyman license to perform work under the general supervision of a Master Plumber.

The authority having jurisdiction determines the provisions for licensing. State Plumbing Boards determine requirements and provide testing of qualified applicants to become licensed. Plumbing inspectors enforce codes adopted by the AHJ.

All items listed above, except estimated cost of materials are required on an approved plan. Some municipalities base plumbing permit fees on fixture units or estimated cost of total job, but not on material costs.

The most stringent provisions in any plumbing application combines all codes, standards, and manufacturer's installation instructions to ensure the health and safety of the public.

Any of these conditions can prompt the plumbing authority to order the system to be removed or placed in a safe and sanitary condition.

The plumbing authority has the power to disconnect a plumbing system from utilities in the event of an immediate hazard to life or property. The utility company can shut down the utility (i.e. natural gas), but they do not have the authority to disconnect a plumbing system. The Code states that the authority having jurisdiction shall have the authority to disconnect the plumbing system to a building, structure, or equipment regulated by the code in case of emergency, where necessary, to eliminate immediate hazard to life or property. In most scenarios, a municipality controls the water supply and the sewer to structures they supply.

Replacing a VTR and replacing it with an auto-vent would require termination and alteration of existing plumbing. A plumber may replace parts of a valve and remove and reset the same toilet without altering the existing plumbing system and all service calls are not subject to obtaining a permit.

If an employee of the plumbing authority issues a permit erroneously or has been supplied with incorrect information it may be suspended or revoked. If the person performing the plumbing work on the permitted job is not licensed, a citation may be written by a field inspector.

The code requires an air test of 10 psi to be held for a minimum of 15 minutes with no visual drop in pressure.

Mercury was formerly used in test gauges for the testing of gas systems. Because of the health risks that result from exposure to mercury poisoning, many municipalities have prohibited their use in pressure tests and relied on sensitive diaphragm gauges that require yearly certification.

All plumbing permits are required to be issued prior to any plumbing work being started. Beginning any portion of plumbing work before a permit is issued is a violation of the plumbing code. Some jurisdictions require that all permits be posted conspicuously so that they can be seen from the road or street that a property fronts on. In existing homes this is often done by posting the permit in a window where it can be seen easily by a code officer approaching the property. New construction sites often have the permits posted in weather-resistant coverings on poles or posts that are readily visible from vehicular routes.

All plumbing permits are to be signed by a licensed plumbing inspector. The signature of an inspector is the only signature required on a permit.

It is common for a code enforcement office to want a site plan and specifications on file prior to any work being done on an existing sewer or water service. The site plan should show the location of existing piping and the proposed location for new piping.

Backflow assemblies and air gaps are required by code to be inspected once a year. The devices should be tested. They must be working properly and not allowing contamination to the water source of a water distribution system. They are also required to be inspected when they are installed. If any repairs are done to the devices, a test and inspection of the repaired device must be performed. Additional devices that require this same procedure include the following: Double check valve assemblies Reduced pressure detector fire protection backflow prevention assemblies Double check detector fire protection backflow preventers Spill-proof vacuum breakers Backflow preventers on any hose connections Reduced pressure principle backflow preventer assemblies Pressure vacuum breaker assemblies

A Stop Work Order is a very serious matter. Code officers issue and post these orders only when there is an immediate danger or a possible danger pending. Minor code violations will result in a rejection from a code officer, not a Stop Work Order. When a Stop Work Order is issued or posted it must be observed immediately. In other words, stop all work instantly. Contact the issuing code officer for instructions. The code officer's name will be affixed to the Stop Work Order. If you continue to work you and your employer could find yourselves in immense trouble.

If a code enforcement officer finds conditions that may prove to be an issue for health and safety, the inspector has the authority to condemn the use of the building. This action can be appealed, but it must be accepted at the time of the posting of the notice that the building is condemned and no longer available for its previous use. The owner of the property must contact the code officer or code enforcement office to remediate the situation

Trusses are engineered. Regardless of whether they are roof trusses or floor trusses, they must not be cut, notched, drilled, spliced or otherwise altered. When truss integrity is disturbed it can lose its structural ability. Normal cutting, notching and drilling procedures associated with solid wood joists and rafters do not apply to trusses. There are, however, some occasions when a truss must be altered to allow for a plumbing installation. When this is the case, an approved engineer must provide written details on how the truss can be altered to allow for a plumbing installation. Only an engineer can do this.

Pipe protection is a major part of the plumbing trade. The code requires a minimum depth of twelve inches of compacted backfill over any buried pipe. This is used as a means of protecting the pipe. All backfill material must be clean and free of debris. For example, you cannot use backfill material that contains broken bricks, sharp rocks or other objects that may puncture a pipe. It is also important to apply backfill material in small quantities to avoid crushing a pipe or twisting a joint at a fitting. Common practice is to apply six inches of dirt and tamp it. Then another six inches of dirt is added and tamped.

Any plumbing installed in a potential flood area must be protected from the potential effects of flooding. These effects include the risk of the following: • Hydrostatic load and stress • Buoyancy • Hydrodynamic load and stress • Entry of flood water into the plumbing system

Ground corrosive effects on piping must be considered before a plumbing installation is made. If the chemical effects of the ground will compromise certain types of piping material, such as copper, protection for the piping must be put in place. This can take the form of a sleeve or a protective, approved coating on the piping. Under no circumstances shall pipe be installed in corrosive ground conditions without suitable protective measures in place.

When plumbing systems are properly protected from flooding and the design and installation meets with code enforcement approval they may be installed below a design flood elevation.

Any pipe that penetrates an exterior wall is required to be provided with adequate pipe protection. By code, adequate pipe protection is a sleeve that has a minimum diameter that is twice the diameter of the pipe it is protecting. This sleeve is required to prevent the plumbing pipe from being crushed if the exterior wall shifts on the foundation supporting it.

The depth of frost penetration in earth varies from region to region. For example, the frost line in Maine is 4 feet. In a more southern state the frost line could be 18 inches. Local plumbing codes define the depth of a frost line in their jurisdictions. Regardless of the depth of a frost line, plumbing pipes must be installed no less than 6 inches below the established frost line as determined by the local plumbing code. And, at no point is there to be less than 12 inches of ground cover over a buried pipe.

The fire resistant factor must not be compromised. Approved plans and specifications will dictate how penetrations may be made and sealed. Fire ratings will be specified. A typical allowable temperature rise is 325 degrees F above the initial temperature through the penetration on a non-fire side when tested in accordance with ASTM E 814. This is often referred to as a T rating. All fire stopping materials must be code approved.

The maximum distance between pipe supports for plastic DWV piping is four feet. Spacing of pipe supports vary depending on the type of piping being supported and the direction of installation for the piping.

There are many types of adapters that can be used for various conversions and transitions from one type of pipe to another. Male and female adapters can be used on water piping and drainage and venting piping. Compression fittings can be used on water piping and drainage and venting piping. Rubber compression sleeve adapters can be used on drainage and venting piping. Rubber insert adapters can be used to convert bell-and-spigot cast iron piping to plastic piping.

Mechanical joints are approved for joining materials of dissimilar type as well as materials of the same type.

Most plumbing pipe is associated with a grade/fall of one-quarter of an inch of fall per running foot. This is not the case with condensate piping. The amount of grade required for a condensate line is one-eighth of an inch by foot. Why is this? The line is not carrying any solid waste. Only clear water is being conveyed. This s why the amount of fall is less than what would be required for a drainage waste system.

You must follow the manufacturer's installation instructions as they are the primary requirement to observe when installing condensate disposal systems. The plumbing code does require certain piping requirements, such as the amount of grade that must be installed on a drainage pipe. The material used for drainage conveyance must also be of a material approved by the local code. However, the pivotal point of condensate piping requirements is determined by the manufacturer's installation requirements.

All equipment that emits condensate drainage is required to be equipped with a drainage system. This applies to evaporators, ice machines, cooling coils and any other type of equipment that needs to release liquid in the form of clean waste.

All auxiliary drain pans for condensate systems are to be equipped with water-level detection devices that conform to UL 508. The device must shut off any equipment served by the drain pan if an overflow of the drainage pan may occur. Consult the manufacturer's recommendations for any additional requirements that may be needed.

Materials approved for the construction of a condensate drainage system can include any of the following: • Galvanized Steel • Copper • PEX • Polyethylene • ABS • PVC • CPVC • Cast Iron

Condensate drain piping must have a minimum interior diameter of .75 or an inch. This is for a single drainage pipe. If multiple pipes are attached to the main condensate drain the minimum diameter of the arterial drain piping must be enlarged accordingly to accept the additional condensate flowage.

The plumbing code defines the minimum thickness for a number of types of materials, such as metal pans used to collect condensate drainage. Other examples pertain to lead shower bases and even tubular trap thicknesses. The minimum thickness rulings are important since they have been engineered for the purposes to which they are applied.

It is common for modern DWV systems to be tested with air. In the old days water was the most common means of testing. When there is a leak that cannot be found easily, smoke can be used to expose the leak location. Smoke is not used as a primary test method. Air is the test medium of choice. The testing of a DWV system is to be conducted for a minimum of 15 minutes. The minimum test pressure is required to be 10 pounds per square inch (PSI). If only underground plumbing is being tested there must be one riser that is at least ten feet above the main plumbing system.

All Code books refer to pipe, tubing and fittings according to inside diameter with measurements expressed in both English and Metric units.

A Journeyman plumber is not required to be under the direct supervision of a Master Plumber. It is a violation of the plumbing Code for a journeyman plumber to work under a homeowner's permit and to receive payment, for such would require a Master Plumber operating as a business and obtaining the plumbing permit.

All indirect connections require an air gap when discharging into a plumbing system. A discharge line run out to the street is not draining into a plumbing system.

Engineers specify materials that conform to standards but not all products available have been approved yet. The plumbing authority having jurisdiction may approve the use of such products and master plumbers must comply with the administrative authority's decisions.

Some pipe manufacturers list measurement in one foot increments when rolls of pipe are 100' or over, but do not list increments on joints of 21', 20' or less. Brand names, psi rating, and nominal pipe size are required.

Failure to ream or deburr pipe ends can result in all outcomes noted.

A twin ell cannot be used in a drainage system. All other fittings listed can be used in both systems.

Offset flanges are prohibited in drainage and vent systems.

Pipe sleeves are required to be 2 pipe sizes larger than pipe size installed. The other options do not allow for expansion and movement in foundation.

Pipe hangers for PEX tubing must be spaced 32" apart.

The minimum fixture requirements for a single-family home include a toilet, lavatory, bathing unit, kitchen sink, and washing machine connection. Keep in mind that these are minimums. Additional fixtures, such as hose bibs, dishwashers, additional bathroom fixtures and others could be included.

Multi-family units are not required to have an individual washing machine connection. They do require a toilet, lavatory, bathing unit and kitchen sink. A laundry connection can be required when a multi-family dwelling has 20 or more dwelling units. It is not required for individual units. The plumbing code does require one laundry connection for every 20 units in a building. In effect, a 40-unit building is required to have a minimum of 2 laundry connections.

Daycare facilities are usually required to offer one toilet for every 15 people in a daycare. Some codes require that the facilities be split into two different rooms. This can result in the need for two toilets. The required minimum fixture requirements are required to be divided evenly between bathrooms for opposite sexes. This is not always the case. Check your local code to see how it interprets a need for separate facilities.

Employees must not have to walk more than 500 feet to reach suitable restroom facilities. During this walk they are not required to ascend more than one set of steps. Bathrooms under these conditions cannot be installed more than one story above the work area. There are possible exceptions for buildings that house factory workers or industrial workers. The 500 foot rule is the typical standard, but you should check your local code to confirm the local requirements.

Hospitals are required to have a minimum of two water services in case one water service becomes unable to provide adequate water for the needs of the facility. While two separate water services are required, only one water main is required. This permits both water services to be tied into a common water main.

Accessible plumbing facilities are generally required in structures that serve the public. They are not a requirement in residential housing. By real estate standards, a multi-family housing unit is considered to be a residential facility until they exceed five rental units. Even then, accessible plumbing is rarely required in all of the rental units. However, accessible plumbing is required in hotels, motels, commercial bathrooms and similar facilities.

Drinking fountains are not allowed to be installed in public bathrooms.

Plumbers working to meet accessible requirements for plumbing facilities must be aware of both the local plumbing code and the local building code. Additionally, the height of toilets must meet minimum requirements. The point of this is that a plumber must pay attention to both the plumbing and building code when working with accessible plumbing needs. The plumbing code dictates fixtures. Requirements of the building code outline minimum spacing requirements for doors and access. In order to maximize full accessible plumbing facilities a plumber must cross over from both the plumbing and building code.

Handicap toilets are available with heights that include 16 inches, 18 inches and 20 inches. Eighteen inches is the most common height of a standard handicap toilet.

Accessible routes for travel to public restroom facilities are not allowed to pass through kitchens, storage rooms, closets or similar spaces.

There are many types of toilets available. The various types of acceptable toilets include the following: Siphon jet Siphon vortex Siphon wash Reverse trap Blowout

Handicap lavatories are required by code to have a minimum of 21 inches of clearance in front of the lavatory. They must be installed in a way to allow easy access by a person in a wheelchair. A rule of thumb measurement is to create a visual box that is 30 inches by 30 inches in front of a handicap lavatory. If someone can sit in this visual box and use the lavatory easily, the spacing is probably fine. This same rule applies to kitchen sinks.

A handicap lavatory must be installed so that there is no more than 35 inches from the top of the lavatory to the top of a finished floor. When working with accessible plumbing fixtures plumbers must remember that clearance requirements and heights are not the same as they are for typical plumbing installations. The fixtures must be installed in a way to serve the people to whom they are intended to provide plumbing resources.

The maximum height allowed for a kitchen sink is 34 inches from the top of the sink to the top of a finished floor.

The maximum length of a travel route to a unisex toilet facility is 500 feet. A unisex restroom must not be located more than one story above or below a separate-sex restroom. All unisex restroom are required to be served by an accessible route.

Lavatory faucets must be located no farther than 25 inches from the front edge of the lavatory being served by the faucet when the fixture is intended for handicap use.

The maximum operational force required to activate a handicap faucet is five pounds. Faucets must be easy to operate when used for accessible purposes. The type of handles allowed on handicap faucets may include any of the following: Blade handles Wing handles Single handles Senior-units Push-button handles

Bathtubs installed for handicap use are required to have seats and grab bars. The grab bars are to have a minimum diameter of 1.25 inches and not more than 1.5 inches. These bars must be at least 24 inches in length. Bars are to be installed horizontally. There should be grab bars in the area of the seat provided for the bathing unit. Design and strength requirements for grab bars are provided in the local building code. A seat for a handicap bathtub may be of an integral type or a removable type.

Hoses installed for the operation of personal shower units in handicap bathing units are required to have a minimum length of five feet.

A kitchen sink installation requires a minimum toe space that is at least nine inches high and nine inches deep. This can be a common element of an installation for a plumber to overlook, especially when the base cabinet is made as a custom cabinet. Production cabinets should meet minimum standards for both the building and plumbing code. But this may not be the case with a handcrafted cabinet. It is wise to check all potential code violations prior to making a plumbing installation.

A handicap shower is to have a seat that is no wider than 16 inches. The seat is to be mounted along a sidewall of the shower and it should run the full length of the shower. A height requirement for the seat requires that the seat be installed at a height of not less than 17 inches and not more than 19 inches. This height is to be measured from the finished floor.

Any lever or button that is used to control the operation of a drinking fountain is to be mounted on either the side or the front of the plumbing fixture. These are the only two locations that are acceptable.

Both toilets and bidets require a minimum open floor space of 30 inches to be installed. This is to allow a minimum of 15 inches of clear space from the center of the fixture drain to the nearest fixture, wall or obstruction. Essentially, a plumber can measure from one obstruction to another and determine if there is 30 inches between them. If there is, the center of the drain for either a toilet or bidet can be installed in the center of the space. It is not required that the fixture be centered in open space, but there must be at least 15 inches from the center of the drain to the nearest obstruction.

Plumbing inspectors can consider several factors when inspecting the installation of plumbing fixtures. Fixtures are to be installed level. They are not to be installed in a manner that makes them crooked. As an example, the tank of a toilet should have the same distance measured from the edge of the tank to the back wall on the left side that it does on the right side. Good workmanship is always a consideration in any plumbing installation. Even adequate space for proper cleaning can be considered. In the end, all fixtures must be installed in a code-compliant manner.

Toilets can have reverse traps. A blowout toilet bowl is also acceptable. Siphon jet bowls are common and a wash down toilet is fine.

Closet bolts are normally made of brass. They must be made of some type of material that is resistant to corrosive action. Otherwise the bolts will deteriorate over time and the toilet will no longer be secured to the closest flange. When a closet flange, which is recommended, is not used, the lag bolts used to secure a toilet are required to be brass or some other non-corrosive material.

The minimum unobstructed opening of egress for a shower door installed on a typical shower is 22 inches.

In this scenario you will not install any of the options offered in the question. Temperature actuated flow reduction valves are not a suitable replacement for a balanced pressure valve, a thermostatic valve or a combination shower and tub valve. The simple solution is to install an anti-scald mixing valve.

Grab bars are not allowed to be installed below faucets in bathing units. For safety reasons the code requires the bars to be installed above faucets. One reason is to discourage people from grabbing the faucet as a support device.

The device used to block the drainage opening of a bathtub can be one of any of the following: • Plunger stoppers • Rubber stoppers • Lift-and-turn stoppers • Push-pull stoppers • Snap-down-pop-up stoppers

If a tub waste is installed with the use of slip nuts and washers an access panel to service the tub waste is required. Solid, permanent connections for tub wastes, such as solvent-weld joints, do not require an access panel. The reason for this is that the washers used with slip-nut connections may need to be replaced from time to time. Settling of a building foundation can shift and cause slip-nut connections to leak. Therefore, anything other than permanent joints made on tub wastes require the installation of a removable access panel to allow for proper inspection and servicing.

All dishwashers are required to discharge their waste through an air gap. This is to prevent back siphonage. Without the use of an air gap there is a risk that dirty drain waste water could be sucked back into a dishwasher. This could introduce bad bacteria into the fixture. One alternative to the use of an air gap is the installation of a backflow preventer on the drainage line. However, the common installation calls for an air gap to be mounted on the deck of a kitchen sink or countertop. The dishwasher drain hose connects to one end of the air gap. A separate hose attaches to the other end of the device and conveys the waste water to the general drainage system. Since the waste passes through open air at the air gap, the risk of back siphonage is eliminated.

Water coolers are required to have the drinking delivery device located at the front of the drinking unit. When water is called for it is to flow upward for a minimum distance of four inches. Levers and buttons that are used to control the flow of water may be mounted on either the front or the side of a driving fountain.

Wastewater from a washing machine should discharge into an indirect waste receptor. What does this mean? It is not complicated. A typical installation has the discharge hose for the washing machine discharging into the open end of a two-inch drainage pipe that is trapped. Another acceptable means of discharge is for the washing machine hose to hang over the rim of a laundry sink and discharge wastewater into the trapped sink drain. This type of piping arrangement is known as an air break and it prevents back siphonage.

The minimum size of a drain pipe accepting the discharge from a garbage disposer is 1.5 inches. The connection must be a solid connection that does not use an air break or an air gap. The drainage pipe is to be trapped. Garbage disposers can be discharged into a continuous waste drain under a kitchen sink. Or, it may be trapped and discharged directly into the sanitary drainage system. Garbage disposers do require a water source, which is usually a kitchen faucet. Most garbage disposers are mounted to one of the drainage holes in a kitchen sink.

Floor drains are required to discharge into a drain pipe that has a minimum diameter of two inches. This should go without saying since the minimum diameter of a drain pipe installed below concrete is two inches. Every floor drain must be trapped and they are typically required to be provided with a vent. Removable strainers for the floor drains are also a code requirement. All removable strainers are required to be readily accessible.

All bidets are required to be protected from back siphonange. A vacuum breaker is normally used for this purpose. If a backflow preventer is not an integral part of a bidet being installed you must provide protection for the fixture in the supply piping from the water distribution system.

The minimum drain diameter for a shower drain is two inches. Bathtubs are allowed to have drains with 1.5-inch diameter drains. This is because the bathtub can retain water as it is drained. Showers do not have the high flood-level rims that bathtubs do. Because of this, they must be drained more quickly. Shower drains are to be trapped and vented. All shower drains are required to be equipped with removable strainers.

When measured from the surface of a shower drain the shower walls must extend 70 inches above the drain.

Sheet lead used for a shower pan lining must have a minimum weight of no less than four pounds per square foot. The lead is to be coated with an asphalt paint or other approved coating. The sheeting must be insulated from any conducting substances, except the drain connection. Fifteen-pound asphalt felt, or an equivalent thereof, is the normal means of insulating the sheet lead. Any sheet lead that must be joined is to be joined by burning.

Drinking fountains and water coolers must not be installed in rooms where toilet facilities exist.

Ballcock assemblies for toilets are required by code to be of an anti-siphon design. It remains possible to buy ballcocks that do not meet this criteria, but they are not approved by the plumbing code standards.

Sheet copper that is used as a liner for a shower must have a minimum weight of 12 ounces per square foot. Some suitable form of insulation is required to be applied between the sheet copper and the subflooring that exists for a shower installation. This is most often done with 15-pound asphalt felt, but the insulation can be of some other equivalent material.

Commercial garbage disposers are big beasts. They usually sit on a tripod set of legs to support their weight. A minimum diameter of a drain pipe for these machines is two inches. They require their own drainage piping and trap. Do not confuse the code regulations for residential garbage disposers with the requirement for commercial garbage disposers. A cold water source must be available to the disposer. The water source can be of an automatic type. Commercial garbage disposals are not allowed to be connected to grease interceptors.

Any piping used in conjunction with a sterilizer is required to be accessible. It is not required to be readily accessible. Remember that readily accessible means that you can see and touch the piping without removing anything. Accessible plumbing can be concealed by a removable access panel.

Garbage can washers are common commercial plumbing fixtures. They must be supplied with a water source and must be equipped with a backflow preventer or an air gap. Every garbage can washer is required to have an individual trap. Discharge from the fixture must pass through an approved, removable strainer to prevent large particles from entering a sanitary drainage system.

Urinals must be equipped with individual flush valves. A single flush valve is not allowed to operate more than one urinal.

Commercial water closets are required to have elongated bowls and elongated seats. Round-front bowls are allowed for residential use, but they are not allowed for commercial applications. Commercial toilet seats are required to be hinged and they are required to have split fronts.

Clinical sinks are also known as bedpan washers.

Sterilizers are to be connected to steam piping that is installed with a gravity system that controls condensation and prevents moisture from entering the sterilizer. Steam vapors are required to be controlled. An indirect waste connection is a requirement for the appropriate installation of a sterilizer. All sterilizers are required to have leak detectors. This type of unit is considered a special fixture.