Written by IAPMO 6:37 pm Answers and Analysis Q&A

Answers & Analysis | Second Quarter 2024

Taken from the Online Editions of the UPC & UMC Answers & Analysis

SUBJECT: Decorative Water Fountains 

SECTION: 406.1 (2021 UPC) 

1. Does the UPC regulate the installation of decorative water fountains? 

2. If yes, are decorative water fountains required to be third-party listed in accordance with Section 301.2? 

3. If yes, are the pipe and fitting materials used in decorative fountains required to comply with those listed in Table 604.1 and Table 701.2 for water supply and waste, respectively? 

1. Yes, the UPC regulates the installation of decorative water fountains and similar fixtures which require water, waste connections or both. These water features must be submitted to the Authority Having Jurisdiction prior to installation. 

2. No, many of these ornamental fixtures are built on the job. 

3. All materials used to complete water and/or waste connections must meet recognized standards set forth by the Uniform Plumbing Code. Materials must be installed to provide backflow protection and trap seal protection. 

SUBJECT: Backflow Prevention 

SECTION: 602.3 (2021 UPC) 

1. Do water treatment systems, such as water softeners, reverse osmosis systems, etc. require a backflow device based on Section 602.3? 

2. Is backflow protection of water treatment system only required when required by the manufacturer and/or listing? 

Comment: Certain water treatment systems, if installed improperly or due to reverse flow can introduce dirt and sediment into the potable water system and significantly affect the quality of the water. 

1. Under section 602.3, Backflow Prevention, a backflow device is required to protect the potable water supply if there is any possibility of pollution or contamination from a water treatment system. A water treatment device connecting directly to the potable water supply which potentially introduces contaminates and/or pollutes a potable water supply system, shall be protected by the appropriate backflow protection as specified in Table 603.2. If the water treatment system utilizes a discharge line into a drainage system, the discharge shall be through an air gap, potentially in addition to a backflow prevention device. 

2. Determining the potential for contamination or pollution and/or backflow requirements should be through applicable standards and manufacturer’s product information. Check with Authority Having Jurisdiction. 

Pollution is defined by Section 218.0 as an impairment of the quality of the potable water system to the degree that does not create a hazard to the public health, but which does adversely and unreasonably affect the aesthetic qualities of such potable water for public use. Also defined as “low hazard”. 

Contamination is defined by Section 205.0 as an impairment of the quality of the potable water system that creates a hazard to the public health through poisoning or the spread of disease by sewage, industrial fluids, or waste. Also defined as high hazard. 

SUBJECT: Downdraft Appliance Ventilation 

SECTION: 518.1 (2021 UMC) 

1. Does the code address that Type II downdraft exhaust systems are not allowed for non-grease and non-smoke appliances? 

2. Can we use Type II downdraft exhaust systems for non-smoke and non-grease appliances in our design? 

1. No. Section 519.5 (2) of the Uniform Mechanical Code states that a Type II Hood Exhaust horizontal termination shall not terminate less than 10 feet from operable openings to buildings. Section 519.5 (1) of the UMC also states that if a Type II Hood Exhaust outlet is a horizontal termination the exhaust termination shall be at least 40 inches above the roof’s surface, a minimum distance of 10 feet from the property line, and the exhaust flow shall be directed away from the roof surface. Additionally, kitchen exhaust air is listed as Class 2 Air, which is “…inappropriate for transfer or recirculation to spaces used for different purposes.” 

2. No. Section 502.2.1 of the UMC states that environmental air ducts shall terminate not less than 3 feet from openings into the building. 


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Last modified: June 11, 2024