| section | section | ||
| Air contamination of. | 3 | Natural ventilation, provision of | 4 |
| measurement of quantity of. | 7(7) | Non-habitable rooms, requirements | 8 |
| quantity for mechanical ventilation | 7 (5) | bathrooms | 8(3) |
| recirculation of | 7(6) | height of | 8(1) |
| supply to required ventilation openings.. | 6 | showers | 8(4) |
| Bathrooms | 8(3) | Open fires | 11 |
| Cars, lift | 10 | ||
| Common walls | 12 | Openings, ventilation air supply to | 6 |
| Contamination of air | 3 | for habitable rooms | 5 |
| Cross-ventilation | 5(4) | Parking garages | 9 |
| Courts. | 13 | Partitions and screens in rooms | 5(5) and (6) |
| Design of mechanical ventilation system | 7 (1) | Party-walls. | 12 |
| Dimensions of habitable rooms | 2 | Position of ventilation openings in walls | 5(2) |
| Earthing, electrical. | 7(3) | Recirculation of air.. | 7(6) |
| Fires, open | 11 | Rooms, habitable dimensions of. | 2 |
| Garages, parking | 9 | height of | 2 |
| Habitable rooms dimension of | 2 | open fires in | 11 |
| required ventilation-openings for. | 5 | Rooms, non-habitable height of | 8(1) |
| Heights of habitable rooms | 2 | soil-water fittings in | 8(2) |
| non-habitable rooms. | 8(1) | Screens and partitions in rooms | 5(5) and (6) |
| Interpretation of terms. | 1 | and (6) Shower cubicles. | 8(4) |
| Lift cars | 10 | Soil-water fittings, rooms containing | 8(2) |
| Mechanical ventilation system, requirements for | 7 | Ventilation openings | 7(8) |
| position of openings in walls. | 5(2) | ||
| provision of | 4 | ||
| required openings in habitable rooms | 5 | ||
| Ventilation systems fire precautions | 7 (9) and (10) | ||
| and (10) Walls, common or party- | 12 | ||
1. INTEPRETATION OF TERMS.
In this Chapter—
“clear height of a room “means the vertical distance from floor to underside of ceiling, or, if there is no ceiling, to the underside of rafters, beams, tie-beams or joists;
“court” means an unobstructed open space which abuts one or more of the external walls of a building, and which is located on the same stand as such building:
Provided that, where a court in any stand abuts—
a) A contiguous court on an abutting stand, and the local authority is satisfied that such contiguous court will not be detrimentally altered in size or shape during the life of any building served or to be served by the court first mentioned; or
b) An area on an abutting stand, which area is in terms of any law required to be kept free of any building or structure; or
c) A street;
Such court may, for the purposes of this Chapter, be deemed to include such contiguous court or such area or such street as the case may be;
“floor area” means the plan area of a room measured between internal-finished wall surfaces;
“habitable room” means any room designed for human occupation, but excluding bath-rooms, water-closets, stairways, passageways, lift-cars, photographic darkrooms, sculleries, domestic laundries, cold-rooms or garages used for parking alone;
“natural ventilation” means ventilation by natural means requiring no machinery;
“required ventilation-openings” means openings required to be provided by and complying with the provisions of this Chapter;
“ventilation-opening” means any opening in the wall of a room, whether permanently open or capable of being opened and shut, through which air may flow by natural means into or out of such room.
2. DIMENSIONS OF HABITABLE ROOMS
(1) Every habitable room shall have a clear height of not less than that set out in subsection (2), over the percentage of floor area of such room set out in subsection (3) and shall otherwise comply with the provisions of subsection (4).
(2) The clear height referred to in subsection (1) shall be as follows—
a) In dwellings, 2,4 meter;
b) In shops, 2,9 meters;
c) In all other buildings, 2,6 meters
(3) The percentage of floor area referred to in subsection (1) shall be as follows—
a) Where a steeply pitched roof forms part of the walls or ceiling of such room (as in attics), at least 50 per centum;
b) In all other cases, at least 75 per centum.
(4) Although the requirements of subsections (1) and (2) may have been complied with, in the following portions of a habitable room the minimum clear height shall be 2,1 meters—
a) In any portion of such room leading to or giving access to doors or windows;
b) In any portion of such room at a horizontal distance from the walls of 1,5 meters.
(5) In all habitable rooms, except kitchens, the minimum floor area over which the minimum clear height of the room of 2,4 or 2,6 or 2,9 meters, as the case may be, is maintained shall be 7 square meters, measured exclusive of immovable objects, such as columns, stairways and built-in cupboards, and such minimum floor area shall have a minimum horizontal dimension of 2,1 meters.
3. CONTAMINATION OF AIR
Wherever conditions of high temperature may be created, or where steam, gases, vapor, dust or other impurities in the air may be produced, which may be injurious to health, all rooms or local areas within rooms affected by these conditions shall be provided with ventilation additional to that required by sections 2 and 6 to the satisfaction of the local authority in such a manner as to prevent harm to any person whether within or without such rooms:
Provided that, where noxious gases, vapors or dust are produced, provision shall be made to extract them from the
4. PROVISION OF VENTILATION
Every habitable room shall be provided with natural ventilation, in accordance with the requirements of sections 5 and 6, unless it is provided with mechanical ventilation, in accordance with the requirements of section 7.
5.REQUIRED VENTILATION-OPENINGS FOR HABITABLE ROOMS
(1) Minimum area of openings. – Every habitable room shall have required ventilation-openings in the walls of an aggregate are of not less than 5 per centum of the floor area, but in no case less than 0,5 square meter:
Provided that, in the case of habitable rooms having a floor area exceeding 50 square meters, the local authority may permit ventilation-openings, other than skylights, in roofs of the monitor, saw-tooth or similar types in lieu of part of the ventilation-openings in walls, of an aggregate area not exceeding half the area afore mentioned.
(2) Position of openings in walls. – Subject to the provisions of section 6, required ventilation-openings in the walls of any habitable room shall be so positioned that they are contained in an external wall or walls.
(3) Measurement of are of required ventilation-openings. – In computing the area of required ventilation-openings in the walls of a room, the following provisions shall apply—
a) Such area shall be measured in the plane of the wall;
b) Where ventilation-openings are covered by wire gauze used as mosquito- or fly-screening, the ventilating are shall be taken as 40 per centum of the net area, excluding frames, of the openings obstructed by such gauze.
(4) Requirements for cross-ventilation. —Where the ventilation-openings required under subsection (2) are situated in one external wall, additional ventilation shall be provided by means of –
a) Permanently open ventilation openings having a total effective open area of not less than 0,03 square meter so placed as to secure cross-ventilation and such openings shall be a minimum of 2 meters from the floor; or
b) Other controlled ventilation devices to the satisfaction of the local authority.
(5) Required ventilation-openings in rooms containing screens and partitions. – Where a habitable room, which complies with the requirements of this Chapter, is subdivided by means of screens or partitions which do not exceed 2,1 meters in height, no allowance need be made for the effect of such subdivisions in determining the positions of the required ventilation-openings for such room.
(6) Where subdivisions of a habitable room are formed by screens or partitions higher than 2,1 meters, each such subdivision shall be ventilated either as if it were a separate habitable room or by means of mechanical ventilation to the approval of the local authority.
(7) Mechanical ventilation. – A means of machinal ventilation to argument the natural ventilation requirements of this section may be utilized to the approval of the local authority.
6. AIR-SUPPLY TO REQUIRED VENTIALTION-OPENING
(1) Fresh air shall be admitted to required ventilation-openings contained in external walls directly from the open air, from a court or a street or public place, or else from a roofed porch, veranda or balcony (hereinafter referred to as a “covered area”), complying with subsection (2).
(2) Covered areas supplying outside air to required ventilation-openings to habitable rooms shall not extend more than 4,5 metres away from the face of the wall at a required ventilation-opening:
Provided that such covered areas to habitable rooms in a dwelling may be enclosed, if ventilation-openings, complying with the requirements of subsection (2) of section 5, equivalent to 7 ½ per centum of the combined floor areas of the provided in an external wall.
(3) Where any habitable room has only one external wall containing ventilation-openings, the required ventilation-openings contained in internal walls of the room shall be supplied with air from passages or ducts which communicated with—
a) The open air at points situated either in the roof or in an external wall; or
b) In the case of dwellings, an approved ventilated passage or room which is not a sleeping-apartment.
(4) Where, in a dwelling, a room opens directly into a passage which supplies air to ventilation-openings in an internal wall of any habitable room, it shall be sufficient, if ventilation, in the form of fanlights, is provided to such passage from another room or rooms having an external wall which does not face in the same direction as the external wall of the room concerned:
Provided that no noxious fumes or gases shall be able to enter such passage from any other room.
(5) In all buildings, other than dwellings, a passage which supplies air to ventilation-openings in an internal wall of any habitable room shall be ventilated directly to the open air at least at one end, or shall be mechanically ventilated.
7. REQUIREMENTS FOR MECHANICAL VENTILATION SYSTEM
(1) Where it is proposed to provide mechanical ventilation to any building or part thereof, details of the ventilation system concerned shall be set out in working-drawings, and shall be submitted to the local authority for its approval.
(2) Details of working-drawings shall include the maximum quantity of outside air per minute which such mechanical ventilation system can supply continuously to all the rooms to be ventilated, together with the number of persons for whose simultaneous use such rooms are authorized or intended (herein-after referred to as the “occupancy” of such rooms).
(3) All metal parts of ducts and machinery associated with any mechanical ventilation system shall be electrically bounded to earth.
(4) Any system providing mechanical ventilation in a building shall be maintained in working order, so as to deliver the quantity of air required by sub-section (5).
(5) Every mechanical ventilation system shall—
a) In the case of occupied areas, supply outside or outside-and-recirculated air—
i) Where the occupancy is known, at the rate and in the proportions specified in Table I;
ii. Where the occupancy is unknown, at a rete of 6 cubic meters per hour per square meter of floor area of each room in the proportions specified in Table I;
b) In the case of services areas, supply outside air or extract air at the rates and by the means specified in Table II.
TABLE I
MINIMUM VENTILATION RATES – OCCUPIED AREAS.
| Application | Forced Ventilation unfiltered. | Forced Ventilation filtered. | Air-conditioned spaces |
| Minimum total air supply per person | 30m/h | 30m/h | 30m/h |
| Maximum proportion of recirculated air | Nil | 25% | 50% |
| Minimum propotion of air | 100% | 75% | 50% |
TABLE II
MINIMUM VENTILATION RATES- SERVICES AREAS
| Application | Forced inlet or extract ventilation: filtered | Extract ventilation only |
| Basement car parks | 20 m/m of floor area per hour or 6 air changes per hour whichever is greater | – |
| Kitchens (other than domestic) | 70 m/m of floor area per hour | – |
| Toilets | – | 35 m/m of floor area per hour |
(6) Air may be recirculated only in a mechanical ventilation system and in accordance with the following provisions—
a) Outside air shall be added to the recirculated air at a rate not less than that required by subsection (5);
b) Recirculation of air in a factory, laboratory, workshop or room shall be permitted only if the local authority is satisfied that the recirculated air is sufficiently free from bacteria, dust, fumes, vapours, mists or gases as to be harmless to the occupants of such factory, laboratory, workshop or room;
c) Air shall not be recirculated from passage-ways, stairways, kitchens, water-closets, urinals, toilets, bath-rooms, lobbies, rooms containing soil-water fittings, rest-rooms or garages:
Provided that it shall be permissible to recirculate air from passageways designed as return airways;
d) Except as may be approved by the Ministry of Health, air extracted from hospital operating-theatres or from any room in an infectious diseases hospital shall not be recirculated.
(7) Quantities of air mechanically supplied or extracted from a room or building shall be measured in or at the openings to the ducts conveying the air.
(8) The size and position of the ventilation-openings in the walls of rooms ventilated by mechanical ventilation shall be such that—
a) When air is being supplied by mechanical ventilation systems, its velocity, as measured with a velometer or other approved apparatus at six different points selected at random, being not less than 1,2 meters from the ventilation-openings and at heights varying from 750 millimeters to 2,1 meters above the floor, should not be less than 9 meters per minute, and not greater than 18 meters per minute;
b) No portion of any air-intake opening outside a building shall be at a height of less than 3 meters above the outside ground-level, unless otherwise permitted by the local authority. The positions of all such air-intake openings and of all discharge-points shall be subject to the approval of the local authority, which shall have regard to the possibility of any source of contamination which may be adjacent to any such air-intakes openings or which may be caused by any discharge-points, and to any objection-able noise to owners of adjacent buildings;
c) Where air is exhausted above a pavement of a street, no portion of the air-exhaust opening outside a building shall be at a height of less than 3 metres above the level of such pavement.
(9) Every air-supply system with a capacity of 25 000 cubic meters per hour or larger, or such a system supplying a building of more than three storeys, shall be capable of being automatically and manually stopped in case of fire. The position of the manual stopping-device shall be determined by the local authority.
(10) Any exhaust system from which the air exhausted can be wholly or partially returned to the building by a supply system, shall be arranged to change over automatically to full exhaust when fire is detected by approved automatic means.
8. REQUIREMENTS FOR NON-HABITABLE ROOMS
(1) Non-habitable rooms used mainly as a means of access, such as corridors, stairways and the like, shall have a clear height of not less than 2,3 meters throughout, and all other non-habitable rooms shall have a clear height of not less than 2,1 meters over at least 80 per centum of the floor area.
(2) Rooms containing soil-water fittings shall comply with the following requirements—
a) The minimum internal floor dimensions of a room containing a water-closet shall be 750 millimeters × 1,4 meters;
b) Every room ventilated by natural ventilation and containing one or more than one soil water fitting (every 500-millimetre length of urinal-stall shall be considered the equivalent of one soil-water fitting) shall be provided with adequate means of permanent ventilation-opening of at least 0,2 square meter for each such fitting;
c) The ventilation-opening shall open –
i) To the open air; or
ii) Into a natural ventilation-shaft with a cross-sectional area of at least 1,5 square meters and with a minimum lateral dimension of 900 millimeters; or
iii) Into a natural ventilation-duct of equal dimensions taken to an approved discharge-point;
d) Where such rooms are ventilated by mechanical ventilation, at least 0,75 cubic meter of air per minute per square meter of floor area of the room shall be extracted by the ventilation system;
e) Every room containing one or more than one soil-water fitting shall be so constructed that such room leads either—
i) Directly into the open air; or
ii) Into a lobby or passage ventilated in accordance with the provisions of sub-section (4) of section 6; or
iii) Into a bedroom in a dwelling or an hotel.
(3) Bath-rooms shall be ventilated as required for habitable rooms in sections 5, 6 and 7.
(4) Shower-cubicles shall comply with the requirements of subsection (2), unless such shower-cubicle is contained in a bath-room of a dwelling or hotel suite.
9. PARKING-GARAGES
(1) In rooms with or without windows, used for the keeping or storage of motor vehicles which may be operated under their own power within such rooms, and which rooms are not used for service, repair or maintenance, the provisions of this section shall be observed.
(2) Rooms with floors not lower than the average adjoining finished ground-level shall be ventilated as follows—
a) In naturally ventilated rooms, when the area of floor of the room is within the range set out in column 1 of Table III, the area of permanent ventilation-openings in the room shall be not less than the area set out in column 2 of that Table;
b) The value of the area of such permanent ventilation-openings may be read off from the curve in Figure 1;
c) In mechanically ventilated rooms, when the area of the floor of the room is within the range set out in column 1 of Table III, the volume of air in cubic meters per minute, which must be extracted from the room, shall be not less than the volume set out in column 3 of that Table;
d) The value of such volume may be read off from the curve in Figure 2;
e) At least half the quantity of air referred to in paragraph © shall be extracted from within a height of 600 millimeters above the floor;
f) Rooms with floors lower than the average adjoining finished ground-level shall be mechanically ventilated, as required in paragraphs (c), (d) and (e);
g) Garage-pits and wells within garages shall have at least 0,3 cubic meter of air per minute per square meter of floor area of the pit or well, extracted by mechanical ventilation, and such air shall be extracted from openings positioned within 300 millimeters of the bottom of the pit or well.
Table III
REQUIREMENTS FOR VENTILATION OF PARKING GARAGES
| 1 | 2 | 3 |
| Area of room Ain square meters | Naturally Ventilated rooms, Minimum area of permanent ventilation openings in room in square meters | Mechanically ventilated rooms Minimum volume of air to be extracted from room in cubic meters |
| Not exceeding 140 141-220 Exceeding 220 | 0,02A (0,1A-11) 0,05A | 0,12A (1,3A-220) 0,3A |
10. LIFT-CARDS
Each passenger lift-car shall be provided with permanently open ventilation-openings equivalent in area to at least 4 per centum of the area of the car-floor, and at least half of this area shall be either in, or not more than 150 millimeters below, the car-roof:
Provided that, where air is extracted by mechanical ventilation from the car, the area of permanently open ventilation-openings need be equivalent to only 2 per centum of the area of the car-floor.
FIGURE 1
NATURALLY VENTILATED ROOMS
FIGURE 2
MECHANICALLY VENTILATED ROOMS
11. OPEN FIRES
Wherever open fires are used within habitable rooms, means of natural ventilation (chimneys) or mechanical exhaust ventilation shall be provided to discharge all resultant gaseous products of combustion above the roof of the building containing the room.
12. COMMON OR PARTY-WALLS
Where separate dwellings are located under a common roof, the walls between such dwellings shall not be perforated by any ventilation-opening.
13. COURTS
(1) No court shall have a horizontal dimension of less than 1,5 meters.
(2) Courts in which all walls exceed 10 meters in height, which are not open to the air on at least one side, shall be ventilated at their lower extremity by ventilated openings communicating with the open air outside the court, or other means approved by the local authority.
14. CHAPTER 11 TO PREVAIL
In the event of any conflict between the provisions contained in this Chapter and the provisions of Chapter 11, the latter shall prevail.