Bathroom, domestic dryer, & range hood - contaminant sources???

[Mech]

2009 IMC

Three story apartment building on college campus. Each apartment has one clothes dryer, one kitchen range exhaust hood, and at least one bathroom (most apartments have 3). Operable windows and mechanical intakes are providing the required ventilation.

Are bathroom, domestic clothes dryer, and domestic kitchen range hood exhausts considered contaminant sources? Section 401.4, item 3, limits the location of intake openings. If they are contaminant sources, then item 3 seems to contradict section 501.2.1 item 3 for required separation distance. By definition, environmental air includes domestic clothes dryer, domestic kitchen range hood, and bathroom exhaust.

401.4 Intake opening location. Air intake openings shall comply with all of the following:

1. Intake openings shall be located a minimum of 10 feet (3048 mm) from lot lines or buildings on the same

lot. Where openings front on a street or public way, the distance shall be measured to the centerline of the

street or public way.

2. Mechanical and gravity outdoor air intake openings shall be located not less than 10 feet (3048 mm)

horizontally from any hazardous or noxious contaminant source, such as vents, streets, alleys, parking lots

and loading docks, except as specified in Item 3 or Section 501.2.1.

3. Intake openings shall be located not less than 3 feet (914 mm) below contaminant sources where such

sources are located within 10 feet (3048 mm) of the opening.

4. Intake openings on structures in flood hazard areas shall be at or above the design flood level.

401.6 Contaminant sources. Stationary local sources producing airborne particulates, heat, odors, fumes, spray, vapors, smoke or gases in such quantities as to be irritating or injurious to health shall be provided with an exhaust system in accordance with Chapter 5 or a means of collection and removal of the contaminants. Such exhaust shall discharge directly to an approved location at the exterior of the building.

501.2.1 Location of exhaust outlets. The termination point of exhaust outlets and ducts discharging to the outdoors shall be located with the following minimum distances:

1. For ducts conveying explosive or flammable vapors, fumes or dusts: 30 feet (9144 mm) from property lines; 10 feet (3048 mm) from operable openings into buildings; 6 feet (1829 mm) from exterior walls and roofs; 30 feet (9144 mm) from combustible walls and operable openings into buildings which are in the direction of the exhaust discharge; 10 feet (3048 mm) above adjoining grade.

2. For other product-conveying outlets: 10 feet (3048 mm) from the property lines; 3 feet (914 mm) from exterior walls and roofs; 10 feet (3048 mm) from operable openings into buildings; 10 feet (3048 mm) above adjoining grade.

3. For all environmental air exhaust: 3 feet (914 mm) from property lines; 3 feet (914 mm) from operable openings into buildings for all occupancies other than Group U, and 10 feet (3048 mm) from mechanical air intakes. Such exhaust shall not be considered hazardous or noxious.

4. Exhaust outlets serving structures in flood hazard areas shall be installed at or above the design flood level.

5. For specific systems see the following sections:

5.1. Clothes dryer exhaust, Section 504.4.

5.2. Kitchen hoods and other kitchen exhaust equipment, Sections 506.3.12, 506.4 and 506.5.

5.3. Dust stock and refuse conveying systems, Section 511.2.

5.4. Subslab soil exhaust systems, Section 512.4

5.5. Smoke control systems, Section 513.10.3

5.6. Refrigerant discharge, Section 1105.7

5.7. Machinery room discharge, Section 1105.6.1

Thanks

 

[97catintenn]

Only if the heat, odors, fumes, spray, vapors, smoke or gases in such quantities as to be irritating or injurious to health.

answer: NO

 

[north star]

( - )

Mech,

IMO, the bathroom and the dryer exhausts would not provide enough

quantities to be considered irritating or injurious [ to me ].....The

kitchen range exhaust hood could provide enough vapors, smells &

particulates to get me irritated.

This may be one of those applications where the college may want

the source of contaminants moved away from any intake openings.

Who has jurisdiction over the installation, ...you or the college?

If them, I would contact them for their directives........If you, then

read my response above.

( + )

 

[mjesse]

2009 IRC does contain this statement ;

the exhaust from dwelling unit toilet rooms, bathrooms and kitchens shall not be considered as hazardous or noxious.



R303.4.1 Intake openings. Mechanical and gravity outdoor air intake openings shall be located a minimum of 10 feet (3048 mm) from any hazardous or noxious contaminant, such as vents, chimneys, plumbing vents, streets, alleys, parking lots and loading docks, except as otherwise specified in this code. Where a source of contaminant is located within 10 feet (3048 mm) of an intake opening, such opening shall be located a minimum of 2 feet (610 mm) below the contaminant source.

For the purpose of this section, the exhaust from dwelling unit toilet rooms, bathrooms and kitchens shall not be considered as hazardous or noxious.

 

[mtlogcabin]

Be carefull with the dryer vent locations. Had an apartment where they where discharging on the exterior 12 inches above the walkways walking surface. Nothing in the code but the plans examiner pointed out this would create an icy condition on the walkways in the winter months. DP was gratefull for the comment and found a different location.

 

[97catintenn]

( - )The

kitchen range exhaust hood could provide enough vapors, smells &

particulates to get me irritated.

( + )

In that case the kitchen hood should be replaced. The code refers to the source producing the fumes. So it doesn't matter what hood you have.

 

[klarenbeek]

Domestic kitchen, bathroom, and dryer exhaust are listed as being environmental air in the definition of environmental air, so by definition they are not hazardous. But, because they are specifically listed as environmental air, the exhaust outlets do need to meet the requirements ofitem 3 of Imc section 501.2.1.

At first glance section 401 seems to contradictsection 501, but it doesn't. Section 401 only deals with keeping fresh air away from hazards, including some types of exhaust. Section 501 deals directly with exhaust outlets and their locations, including in relation to fresh air intakes. Environmental exhaust might not be a hazard, but what is the point of exhausting it out if it can get sucked right back in by a mechanical fresh air intake?