Air and moisture on shipboard : a fragment of applied physiology / by Th. J. Turner.

  • Turner, Thomas J., 1815-1901.
Date:
[1877?]
Catalogue details

Licence: Public Domain Mark

Credit: Air and moisture on shipboard : a fragment of applied physiology / by Th. J. Turner. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    The Revised Statutes of the United states, paragraph 4252, assigns to cadi passenger on a main or poop deck 1(5 clear superficial feet; it the decks are <> feet in the clear. IS dear superficial feet on lower (leeks; no passenger to be carried where the decks arc less than 6 feet in the clear: and where the decks are 7A feet or more in the clear, L4 super- ficial feet is the allowance. The British merchant shipping act assigns 72 cubic feet and V2 super- ficial feet on deck for each person as the minimum space. These meas- urements we must accept provisionally as a standard. This unavoidable overcrowding follows its usual law in increased sick and death rates. How soon the air on these lower decks becomes unfit for the purposes of respiration and consequently detrimental to health, will be made evident from the following facts: The normal amount of carbon dioxide existing in the atmosphere is accepted at t volumes in 10,000, and the limit of respiratory impurities, ;is measured by the increased volume of this gas. is stated by the best authorities to be 6 volumes in 10,000. It must be stated here, with the hope that it may be distinctly understood, that carbon-dioxide is used as the measure of the impurity of the air, not on account of its own special poisonous action, but because (and I quote the words of Hillings) within certain limits its quantity may be taken as the measure of that of really important impurities, and it is almost the only available test for this purpose. The observations of Pettenkofer and Voit, Zoch, Donkin, Parkes, De- Chaumont, repeated by the writer, amount to an absolute demonstration of this fact. Now, in .>() cubic feet oi' still air this limit of impurity is attained by the respiration of a single individual in one minute of time. It follows, therefore, that in vessels of the Hwatara class, under like conditions, the limit is arrived at in 1 '.16; in those of the Richmond class, iii L'.36; and in those of the Miantonomoh class, in t',62. These circumstances, however, seldom or ever obtain, for in masses ot men engaged in work in confined spaces, with a slow-moving air, condi- tions existing in a degree on shipboard, the limit of atmospheric impurity is much sooner attained, for the amount of < '< )> eliminated from the body by respiration alone being more than doubled in passing from a state ot resl to performing work equivalent to walking one mile per hour; that is to say, a man weighing L60 pounds, at rest, expires per hour .71*; of a cubic foot of carbon-dioxide; walking one mile per hour. L.446 cubic feet; walking 2 miles per hour, 2.53 cubic feet; and should the work done be equal to walking three miles per hour, the most useful rate of work, considering the element of time, .'5.275 cubic feet of carbon-dioxide is expired. As a general rule, it may be stated that about 8 cubic inches of CO* are given off per hour for each pound avoirdupois weight of the indi- vidual when at rest.