Report of the Coloured Labour Compound Commission appointed to enquire into the cubic amount of air-space in the compounds of the mines of the Witwatersrand.

Date:
1905
Catalogue details

Licence: In copyright

Credit: Report of the Coloured Labour Compound Commission appointed to enquire into the cubic amount of air-space in the compounds of the mines of the Witwatersrand. Source: Wellcome Collection.

Provider: This material has been provided by London School of Hygiene & Tropical Medicine Library & Archives Service. The original may be consulted at London School of Hygiene & Tropical Medicine Library & Archives Service.

    81/130 (page 47)
    When a fire is alight, there will, therefore, be 33,600 -}- 4,000 = 37,600 cubic Appendix A. feet entering per hour into each room of 4,000 feet capacity which is constructed to accommodate 20 Chinese, and which, in practice, will during five-sevenths of the week contain only 66 per cent, of that number and for two-sevenths of the week 90 per cent. Calculated on these data, the amount of CO2 per 1,000 volumes of air in the room at the end of eight hours is shown as follows :— (le Chaumoiit limit. Haldane limit. No Fire. Fire Burning. Englisli Common Lodging-house. Elementary School- rooms in cold weather. ()(i % boys. !)0 % boys. (;<; % boys. 90% boys. 0'6 I'2 0-67 077 0*64 074 3'3 (Average for 8 hrs. = 27.) 2 6 at end cf i hour ; 4-0 at end of 2 hours ; 5‘0 at end of 3 hours (Average for 3 hours 3 8 ) The ventilation proposed for the Chinese Compound is, therefore, at its wmrst, more than four times as good as in English Common Lodging-houses, and five times better than in many elementarj' schoolrooms in winter. In view, however, of the fact that these conclusions are based upon theoretical formula and data, which, in some instances, cannot be defined at present with accuracy, it will be advisable to test them in practical application, both in regard to the actual respiratory impurity which results and the necessity in cold weather for warming the incoming air. For the purpose of the calculations as to air-delivery which this enquiry has involved, it has been necessarj' to assume some average difference of temperature inside and outside compound sleeping-rooms. From consideration of the maximum and minimum night temperature for the summer and for the winter months, and of the results of hourly observations made on the night of the I3th-i4th June inside and outside compound sleeping-rooms in which the proposed conditions for Chinese were constituted, it has been thought safe to accept 10° Fah. as a fair expression of this difference, except on very warm nights, when it is reasonable to suppose that the doors and windows of these rooms will be kept freely open. Actual measurement was also made, by the courtesy of the Engineer of the Jumpers Deep, of the temperature of the hot air escaping through a 6-inch flue over a fire in a sleeping-room. At the rim of the hood of the chimney it was 260° Fah., whilst both at 8 feet from the floor and 8 feet from the top of the chimney it was 143° Fah., the actual measured amount of air escaping per hour being about 7,350 cubic feet. It is, therefore, thought that it is reasonable to assume that if there were a second tube of 12 inches diameter surrounding the 6-inch flue, and provided with a bell-shaped opening 8 feet from the ground, the temperature of the air in this second tube would be 50° Fah. higher than the external air. j