A handbook of house sanitation : for the use of all persons seeking a healthy home ; a reprint of those portions of Mr. Bailey-Denton's lectures on sanitary engineering given before the school of military engineering, Chatham, which related to the "dwelling."

  • Denton, J. Bailey (John Bailey), 1814-1893.
Date:
1882
Catalogue details

Licence: Public Domain Mark

Credit: A handbook of house sanitation : for the use of all persons seeking a healthy home ; a reprint of those portions of Mr. Bailey-Denton's lectures on sanitary engineering given before the school of military engineering, Chatham, which related to the "dwelling.". Source: Wellcome Collection.

Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.

    16/254 (page 4)
    y. Attainable Standard of Air.—According to Dr. Angus Smith a favourable, though not the purest specimen of air, may be taken to contain by weight of oxygen 20-96, of nitrogen 79-00, and of carbonic acid -04 per cent., with a varying quantity of watery vapour. We may take these figures as representing a fair attainable standard of pure air, and may therefore conclude that directly these proportions are altered by an increase of carbonic acid and a mixture of other foreign matters involving a reduction of oxygen the quality of the air is lowered. [Air in fact with a very small loss of oxygen is percep- tibly deteriorated, if the place ■ of the oxygen is occupied with •carbonic acid and exhalations from the person, although we are not able to say how far this is the case when carbonic acid alone is substituted for this small amount of oxygen,—Angus Smith.'] The diminution of oxygen is, however, very sensibly felt directly its quantity is reduced as low as 20-75 P^^ cent. VI. Quantity of Air Respired by Human Beings.—To understand to what extent the loss of oxygen, and an excess of carbonic acid mixed with deleterious foreign substances may etfect the health of human beings, it should be understood that Professor Huxley states that in respiration about 350 cubic feet of air pass through the lungs of each individual per diem. '* In passing through the lungs the air would lose from 4 to 6 per cent, of oxygen, arid gain 4 to 5 per cent, of carbonic acid. During 24 hours there would be consumed about 10,000 grains oxygen, and produced about 12,000 grains carbonic acid corresponding to 3,300 grains of carbon. During the same time about 5,000 grains or 9 ozs. of water would be exhaled by the lungs. In 24 hours such a body would vitiate 1,750 cubic feet of pure air, to the extent of i per cent, or 17,500 cubic feet of pure air to the extent of i per 1,000. Taking the amount of carbonic acid in the atmosphere at three parts, and in expired 470 parts in 10,000, such a body would require a supply per diem of more than 23,000 cubic feet of ordinary air, in order that the surround- ing atmosphere might not contain more than i per 1,000 oi carbonic acid (when air is vitiated from animal sources with carbonic acid to more than i per 1,000 the concomitant impu- rities become appreciable to the nose). A man of the weight mentioned (11 stone), ought therefore to have at least 800 cubic feet of well ventilated space. Upon this subject Dr. de Chaumont says that each adult con- sumes in food from 3,500 to 4,000 grains of carbon in 24 hours, i.e., from 8 to 9 ozs., and he exhales as carbonic acid about the same quantity, which is equal to 17 cubic feet of the gas to