CHAPTER 4 VENTILATION - iccsafe.org

1 CHAPTER 4. VENTILATION . SECTION 401 TABLE OPENING SIZES IN LOUVERS, GRILLES AND SCREENS. GENERAL PROTECTING OUTDOOR EXHAUST AND AIR INTAKE OPENINGS. Scope. This CHAPTER shall govern the VENTILATION of MINIMUM AND MAXIMUM OPENING. spaces within a building intended to be occupied. This chap- SIZES IN LOUVERS, GRILLES. ter does not govern the requirements for smoke control sys- AND SCREENS MEASURED IN. OUTDOOR OPENING ANY DIRECTION. tems. Exhaust openings Not < 1/4 inch and not > 1/2 inch VENTILATION required. Every occupied space shall be Intake openings in residential Not < 1/4 inch and not > 1 / 2 inch ventilated by natural means in accordance with Section 402 occupancies Intake openings in other than or by mechanical means in accordance with Section 403. residential occupancies > 1/4 inch and not > 1 inch When required.

2 VENTILATION shall be provided during For SI: 1 inch = mm. the periods that the room or space is occupied. Contaminant sources. Stationary local sources pro- Vestibule VENTILATION . Vestibule VENTILATION for smoke- ducing air-borne particulates, heat , odors, fumes, spray, proof enclosures shall be in accordance with the Florida vapors, smoke or gases in such quantities as to be irritating or Building Code, Building. injurious to health shall be provided with an exhaust system in accordance with CHAPTER 5 or a means of collection and Opening location. Outside air exhaust and intake removal of the contaminants. Such exhaust shall discharge openings shall be located a minimum of 10 feet (3048 mm) directly to an approved location at the exterior of the building. from lot lines or buildings on the same lot.

3 Where openings front on a street or public way, the distance shall be measured SECTION 402. to the centerline of the street or public way. NATURAL VENTILATION . Exception: Use Group R-3. General. Natural VENTILATION of an occupied space shall be through windows, doors, louvers or other openings Intake openings. Mechanical and gravity outside to the outdoors. air intake openings shall be located a minimum of 10 feet VENTILATION area required. The minimum openable area to (3048 mm) from any hazardous or noxious contaminant, the outdoors shall be 4 percent of the floor area being ventilated. such as vents, chimneys, plumbing vents, streets, alleys, parking lots and loading docks, except as otherwise spec- Adjoining spaces. Where rooms and spaces with- ified in this code.

4 Fresh air intakes shall not be located out openings to the outdoors are ventilated through an closer than 10 ft (3048 mm) from any chimney or vent adjoining room, the opening to the adjoining rooms shall outlet, or sanitary sewer vent outlet. be unobstructed and shall have an area not less than 8 per- cent of the floor area of the interior room or space, but not Exhaust openings. Outside exhaust openings less than 25 square feet ( m 2 ). The minimum openable shall be located so as not to create a nuisance. Exhaust air area to the outdoors shall be based on the total floor area shall not be directed onto walkways. being ventilated. Openings below grade. Where openings below Outdoor opening protection. Air exhaust and intake grade provide required natural VENTILATION , the outside hor- openings that terminate outdoors shall be protected with cor- izontal clear space measured perpendicular to the opening rosion-resistant screens, louvers or grilles.

5 Openings in lou- shall be one and one-half times the depth of the opening. vers, grilles and screens shall be sized in accordance with The depth of the opening shall be measured from the aver- Table Openings shall be protected against local weath- age adjoining ground level to the bottom of the opening. er conditions. Outdoor air exhaust and intake openings locat- ed in exterior walls shall meet the provisions for exterior wall Contaminants exhausted. Naturally ventilated spaces opening protectives in accordance with the Florida Building having contaminant sources as covered in Section shall Code, Building. be provided with an exhaust system in accordance with CHAPTER 5 or an approved means of collection and removal of the contaminants. FLORIDA BUILDING CODE MECHANICAL - TABLE Bathrooms.

6 Rooms containing bathtubs, show- ers, spas and similar bathing fixtures shall be mechanical- VENTILATION rate. VENTILATION systems shall be designed ly ventilated in accordance with Section 403. to have the capacity to supply the minimum outdoor air flow rate determined in accordance with Table based on the Openings on yards or courts. Where natural VENTILATION occupancy of the space and the occupant load or other is to be provided by openings onto yards or courts, such yards or parameter as stated therein. The occupant load utilized for courts shall comply with the requirements of the Florida design of the VENTILATION system shall not be less than the Building Code, Building. number determined from the estimated maximum occupant load rate indicated in Table Where peak occupancies SECTION 403 of less than three hours duration occur, the outside air flow MECHANICAL VENTILATION rate may be determined on the basis of average occupancy for the space for the duration of the system, provided the VENTILATION system.

7 Mechanical VENTILATION shall be average occupancy used is not less than one-half the maxi- provided by a method of supply air and return or exhaust air. mum. VENTILATION rates for occupancies not represented in The amount of supply air shall be approximately equal to the Table shall be determined by an approved engineering amount of return and exhaust air. The system shall not be analysis. The VENTILATION system shall be designed to supply prohibited from producing a negative or positive pressure. the required rate of VENTILATION air continuously during the The system to convey the VENTILATION air shall be designed period the space is occupied, except as otherwise stated in and installed in accordance with CHAPTER 6. other provisions of the code. Exception: The occupant load is not required to be deter- VENTILATION supply systems shall be designed to deliver the mined, based on the estimated maximum occupant load required rate of supply air to the occupied zone within an occu- rate indicated in Table where approved statistical pied space.

8 The occupied zone shall have boundaries measured data document the accuracy of an alternate anticipated at 3 inches (76 mm) and 72 inches (1829 mm) above the floor occupant density. and 24 inches (610 mm) from the enclosing walls. TABLE Outdoor air required. The minimum VENTILATION rate REQUIRED OUTDOOR VENTILATION AIR. of required outdoor air shall be determined in accordance ESTIMATED. with Section MAXIMUM OUTDOOR AIR. OCCUPANT LOAD, [cubic feet per PERSONS PER minute (cfm) per Exception: Where the registered design professional 1,000 SQUARE person] UNLESS. demonstrates that an engineered VENTILATION system design OCCUPANCY CLASSIFICATION FEET' NOTED*. will prevent the maximum concentration of contaminants Correctional facilities Cells 20 20. from exceeding that obtainable by the rate of outdoor air Dining halls 100 15.

9 VENTILATION determined in accordance with Section , Guard station 40 15. the minimum required rate of outdoor air shall be reduced Dry cleaners, laundries in accordance with such engineered system design. Coin-operated dry cleaner 20 15. Coin-operated laundries 20 15. Commercial dry cleaner 30 30. Recirculation of air. The air required by Section Commercial laundry 10 25. shall not be recirculated. Air in excess of that Storage, pick up 30 35. required by Section shall not be prohibited from Education being recirculated as a component of supply air to build- Auditoriums 150 15. Classroom 50 15. ing spaces, except that: Corridors . 1. VENTILATION air shall not be recirculated from one Laboratories 30 20. dwelling to another or to dissimilar occupancies. Libraries 20 15.

10 2. Supply air to a swimming pool and associated deck Locker rooms cfm/ft2. Music rooms 50 15. areas shall not be recirculated unless such air is Smoking loungesb 70 60. dehumidified to maintain the relative humidity of Training shops 30 20. the area at 60 percent or less. Air from this area shall Food and beverage service not be recirculated to other spaces. Bars, cocktail lounges 100 30. Cafeteria, fast food 100 20. Dining room 70 20. Transfer air. Except where recirculation from Kitchens (cooking)f 20 15. such spaces is prohibited by Table , air transferred from occupied spaces is not prohibited from serving as Hospitals, nursing and convalescent homes makeup air for required exhaust systems in such spaces as Autopsy roomsb cfm/.ft2. kitchens, baths, toilet rooms, elevators and smoking Medical procedure rooms 20 15.