### Building (Standards of Sanitary Fitments, Plumbing, Drainage Works and Latrines) Regulations 《建築物(衞生設備標準、水管裝置、排水工程及廁所)規例》

65. Capacity
(1) Every septic tank shall have such minimum capacity as shall be determined by the Building Authority in the manner prescribed by paragraph (2):
Provided that no septic tank shall have a capacity of less than 2.3 m3 or more than 41 m3. (L.N. 294 of 1976)
(2) (a) The septic tank shall be of such capacity as to be capable of storing the quantity of soil and waste discharged thereto during any one day.
(b) The quantity of soil and waste discharged shall be calculated according to the rate of consumption of potable and flushing water which, in the opinion of the Building Authority, is appropriate to the type, size and use of the building. (L.N. 361 of 1980)
(3) For the purposes of this regulation, the number of persons using or likely to use the soil and waste fitments installed in any building shall be determined by the Building Authority.
(L.N. 361 of 1980)

66. Construction
(1) Every septic tank shall—
(a) have a depth of at least 1.2 m but not more than 1.8 m from the invert of the inlet to the floor of the tank;
(b) have a length not less than 3 times but not more than 4 times its width;
(c) be provided with adequate means of access for the inspection and cleansing of each chamber. (L.N. 361 of 1980)
(2) The sides of every septic tank shall be constructed of—
(a) brickwork in cement mortar not less than 215 mm thick;
(b) concrete not less than 125 mm thick; or (L.N. 439 of 1990)
(c) other approved material.
(3) The foundation and floor of every septic tank shall be constructed of concrete not less than 150 mm thick. (L.N. 439 of 1990)
(4) All internal faces (including the floor) of every septic tank shall be—
(a) rendered in cement mortar; or
(b) faced with other approved material,
so as to provide a smooth, impervious surface.
(L.N. 294 of 1976)

67. Dip pipes
The inlet to and the outlet from every septic tank shall be by means of dip pipes of such depth as to avoid disturbance of the top scum.

68. Ventilation
In every septic tank the space between the top of the water level and the underside of the cover shall be—
(a) adequately ventilated; or
(b) provided with adequate means for drawing off gases.

### Building (Standards of Sanitary Fitments, Plumbing, Drainage Works and Latrines) Regulations 《建築物(衞生設備標準、水管裝置、排水工程及廁所)規例》

69. Situation of cesspools
No cesspool shall be situated—
(a) within 20 m of any spring, stream of water or well, the water from which is used, or likely to be used, for drinking or domestic purposes or for the manufacture or preparation of articles of food or drink for human consumption or for the cleansing of vessels used in the manufacture or the preparation of such articles; or 
(b) within 15 m of any building in which any person resides or works. 
(L.N. 294 of 1976)

70. Disposal of contents
Every cesspool shall be so situated that there shall be adequate means for removing its contents without carrying them through any building in which any person resides or works.

71. Capacity
(1) Every cesspool shall have such minimum capacity as shall be determined by the Building Authority in the manner prescribed by paragraph (2).
(2) (a) The cesspool shall be of such capacity as to be capable of storing the quantity of soil and waste discharged thereto during a period of one month.
(b) The quantity of soil and waste discharged shall be calculated at the rate of 135 L thereof for each day for each person using or likely to use the soil fitments or waste fitments installed in the building for which the cesspool is provided. (L.N. 294 of 1976; E.R. 3 of 2020)
(3) For the purposes of this regulation, the number of persons using or likely to use the soil fitments or waste fitments installed in any building shall be determined by the Building Authority.

72. Construction
(1) Every cesspool shall be—
(a) constructed of—
(i) brickwork in cement mortar;
(ii) concrete; or (L.N. 439 of 1990)
(iii) other approved material;
(b) so constructed and finished as to be impervious to liquid either from the inside or the outside;
(c) covered with a reinforced concrete cover;
(d) provided with adequate access for cleaning purposes; and
(e) adequately ventilated.
(2) The internal faces of every cesspool shall be rendered with cement mortar.

### Building (Standards of Sanitary Fitments, Plumbing, Drainage Works and Latrines) Regulations 《建築物(衞生設備標準、水管裝置、排水工程及廁所)規例》

73. Testing of drainage works and procedure thereupon
(1) The registered general building contractor or the registered specialist contractor appointed in respect of any drainage works shall, on the completion of such works, but before any trenches in which drains or sewers have been laid are filled in, apply, in writing, to the Building Authority for such works to be tested.
(2) On such application the Building Authority may inspect and test the drainage works and shall—
(a) if he is satisfied with the result of such test, notify the registered general building contractor or the registered specialist contractor appointed in respect thereof accordingly; or
(b) if he is not so satisfied, order such work to be carried out as may be necessary to cause such works to comply with these regulations.
(3) An order made under paragraph (2)(b) shall be in writing and shall specify—
(a) the work to be carried out; and
(b) the period of time within which such work must be carried out.
(4) After the expiry of the period specified in any such order, the Building Authority shall again inspect and test the drainage works and, where, by reason of any failure to comply with such order, more than one further inspection and test is necessary, shall inspect and test such works such number of times as may be necessary and, when he is satisfied with the results of any test, shall notify the registered general building contractor or the registered specialist contractor appointed in respect of such works accordingly.
(5) In respect of every inspection and test made in accordance with the provisions of paragraph (4), the registered general building contractor or the registered specialist contractor appointed in respect of the drainage works shall pay the prescribed fee. 
(6) If the Building Authority does not test any drainage work within 4 days of the receipt of an application therefor under paragraph (1), the trenches in which any drains and sewers have been laid may be filled in.
(L.N. 516 of 1997)

74. Power of Building Authority to require drainage trenches to be opened
Save where a trench in which drains or sewers have been laid is filled in pursuant to the provisions of regulation 73(6), if a trench in which drains or sewers have been laid is filled in before the Building Authority has, under regulation 73, notified the registered general building contractor or the registered specialist contractor appointed in respect of the drainage works that he is satisfied with the result of a test, the Building Authority may require such registered general building contractor or the registered specialist contractor to open and uncover the drainage works in order to enable him to carry out an inspection and test.
(L.N. 516 of 1997)