UNITED STATES DEPARTMENT OF AGRICULTURE 
DEPARTMENT BULLETIN No, 1373 
Washington, D.C. 
Issued February, 1926 
Revised March, 1928 
DUST CONTROL IN GRAIN ELEVATORS 
By Hylton R. Brown and J. O. Reed, Associate Engineers, 
Chemical and Technological Research, Bureau of Chemistry and Soih 
CONTENTS 
Page 
Introduction 1 
Purpose of investigation... — 2 
Procedure 2 
Methods of dust control. 3 
Dust collection. 4 
Dust removal 22 
Natural ventilation 31 
Mechanical ventilation.. 33 
Page 
Dust-control equipment ._ 34 
Fans 34 
Piping system 34 
Dust collectors 35 
Grain traps 35 
Suction regulators 36 
Effect on grain weights... 46 
Conclusions 48 
INTRODUCTION 
From 1919 to 1925 dust explosions in the United States in plants 
handling grain and grain products caused the loss of 133 lives, injury 
to 130 employees, and property damage amounting to more than 
$12,000,000. As more than one-fourth of the loss in life and more 
than one-half of the property damage occurred in grain elevators, 
special attention has been directed to the elimination of the dust- 
explosion hazard in the grain elevating industry. 
The requirements for a dust explosion are (1) dust in suspension 
in air in a certain proportion, and (2) some means of igniting this 
dust and air mixture. 1 Such explosions, then, may be prevented by 
using equipment which will eliminate all sources of ignition around 
the plant, or by controlling the dust and air mixture so that no 
explosive dust clouds can be formed. For some time attention was 
directed to the elimination of open flames around plants where it 
was possible for the explosion hazard to exist. When it was found 
that electric sparks, blown fuses, broken electric lamps, hot bearings, 
friction fires, metallic sparks, static electricity, and fires caused by 
spontaneous combustion could ignite the dust, however, attention 
was turned to the development of equipment for controlling the dust. 
More efficient work can be done in a clean, orderly, and well-run 
plant than in one where dust clouds are permitted to form. Further- 
more, dusty atmospheres may affect the health of the workmen. 
Aside from reducing the dust-explosion hazard, then, the installation 
of dust-collecting equipment improves the .health and efficiency of 
the workmen. 
1 D. J. Price and H. H. Brown, "Dust Explosions," published by National Fire Protection As 
tion, Boston, Mass., 1922. 
Acknowledgment.— All drawings were made by Robert M. Baker. 
83278°— 28 1 
