SEASONAL DISTRIBUTION OF INDUSTRIAL ACCIDENTS DUE TO LIGHTING CONDITIONS AND TO OTHER CAUSES

                            Percentage due to
                    Lighting conditions Other causes

July                      4.8           5.9
August                    5.2           6.2
September                 6.1           6.9
October                   8.6           8.5
November                 10.9          10.5
December                 15.6          12.2
January                  16.1          11.9
February                 10.0          10.5
March                     7.6           8.8
April                     6.1           6.9
May                       5.2           5.8
June                      3.8           5.9

The figures in one column have no direct relation to those in the other; that is, each column must be considered by itself.  It is seen from the foregoing that about half the number of the accidents due to poor illumination occurred in the months of November, December, January, and February.  These are the months of inadequate illumination unless artificial lighting has been given special attention.  The same general type of seasonal distribution of accidents due to other causes is seen to exist but not so prominently.  The greatest monthly rate of accidents during the winter season is nearly four times the minimum monthly rate during the summer for those accidents due to lighting conditions.  This ratio reduces to about twice in the case of accidents due to other causes.  Looking at the data from another angle, it may be considered that the likelihood of an accident being caused by lighting conditions is about twice as great in any of the four “winter” months as in any of the remaining eight months.  Doubtless, this may be explained largely upon the basis of morale.  The winter months are more dreary than those of summer and the workman’s general outlook is different in winter than in summer.  In the former season he goes back and forth to work in the dark, or at best, in the cold twilight.  He is not only more depressed but he is clumsier in his heavier clothing.  If the enervating influence of these factors is combined with a greater clumsiness due to cold and perhaps to colds, it is not difficult to account for this type of seasonal distribution of accidents.  A study of the accidents of 1917 indicated that 13 per cent. occurred between 5 and 6 P. M. when artificial lighting is generally in use to help out the failing daylight.  Only 7.3 per cent. occurred between 12 M. and 1 P. M.

[Illustration:  SIGNAL-LIGHT FOR AIRPLANE]

[Illustration:  TRENCH LIGHT-SIGNALING OUTFIT]

[Illustration:  AVIATION FIELD LIGHT-SIGNAL PROJECTOR]

[Illustration:  SIGNAL SEARCH-LIGHT FOR AIRPLANE]

[Illustration:  UNSAFE, UNPRODUCTIVE LIGHTING WORTHY OF THE DARK AGES]

[Illustration:  THE SAME FACTORY MADE SAFE, CHEERFUL, AND MORE PRODUCTIVE BY MODERN LIGHTING]