Page:New York subway ventilation.djvu/11

Rh 1905. Although he made a preliminary report on Oct. 19th, 1905, the main findings were not available for public inspection prior to Jan. 1st, 1907. Many excerpts have been made from this report giving the essentials of the investigation which can readily be verified in substantiation of any statement herein made. Accompanying the report to the Rapid Transit Commission by Prof. Soper was a report from Chief Engineer Rice, which contains amongst other things the following recommendations and suggestions in addition to the cutting of the openings already spoken of and the installation of the so-called refrigerating plant. On page 194 of the report, it was recommended that there should be a complete renewal of the contents of the subway every half hour, which means, as will be noted, the removal of 54,000,000 cubic feet of air per hour. These are very large figures, but the subject and the subway are likewise large propositions, and consequently call for large terms. That this was a very conservative recommendation is clear when it is learned that in good ventilating practice the cubic contents of a building, say of a hospital or a theatre occupied by large numbers of people, are in many cities, required by law to be changed from four to six times per hour.

Installation of Fans

It quickly became obvious to the engineers that the cutting of holes in the roof of the subway was not going to effect a real change of the cubic contents of the subway at all, however it might effect it in spots, hence there were installed at various points in connection with these roof openings some 25 blowers ranging from five to seven feet in diameter driven by electric motors of 15 to 30 H.P. each which combined were capable of exhausting from the subway fully 1,000,000 cubic feet of air per minute. The application of a little arithmetic will show that these fans would then exhaust from the subway an amount of air every hour in excess of the recommendations of the engineers, or in other words, 60,000,000 cubic feet as against the required 54,000,000 feet. Even assuming that these blowers were operated at all times at their full capacity, the question naturally arises, what results were accomplished thereby? Chief Engineer Rice on March 22d, 1906, says in his report, on page 82 that "a large part of the construction vas completed in the Summer (1905) with the result that the subway was noticeably cooler. The refrigeration experiments were also carried on with satisfactory results." If a straw vote were taken from the passengers in the subway during the Summer of 1915, it may very well be doubted that a very large majority would even at this date agree with Chief Engineer Rice in his findings.

In view of the recent accident and fire in the subway, it is most significant to note that the Chief Engineer in his report on page 196