WTnn^

Bulletin No. 333 Series Q, Fuels, 7 

DEPARTMENT OF THE INTERIOR

UNITED STATES GEOLOGICAL SURVEY

GEORGE OTIS SMITH, DIRECTOR

COAL-MINE ACCIDENTS: THEIR 

AND PREVENTION

A PRELIMINARY STATISTICAL REPORT 

BY

CLARENCE HALL AND WALTER O. SNELL1NG

WITH INTRODUCTION liY

JOSEPH A. HOLMES

IN CHATCGE OF TECHNOLOGIC ERANCH

WASHINGTON

GOVERNMENT PRINTING OFFICE

1907
CONTENTS.

Page.

Introduction, by Joseph A. Holmes.................... .................... 3

Statistics relating to accidents in coal mines.......................I......... 5

Fatal accidents in the United States.................................... 5

Number of men killed for each thousand employed..................... 5

Increase in the United States...................................... 5

Decrease in European countries..........'.......................... 6

Protective legislation .......................................... 6

Belgium..................................................... 6

Great Britain................................................. 7

Prussia...................................................... 7

France ...................................................... 7

Comparative summary............................................ 8

Causes of mine accidents.............................................. 8

Fatal accidents from falls of roof ami coal........................... 8

Fatal accidents from gas and dust explosions....................... 10

Fatal accidents from other causes.................................. 11

Number of men killed for each million tons of coal produced............ 11.

United States .................................................... 11

European countries........................................ ...... 12

Conclusions................................................. ........ 13

Prevention of mine accidents.............................................. 14

Safety lamps ..........:..............................'................ 14

Use of- explosives. ............................................'... ..... 15

Storage of explosives.................................................. 18

Shot firers ...............'.................................-.......... 18

Materials used for tamping............................................. 19

Watered zones ....................................................... 19

Aid to the injured..................................................... 19

Enforcement of regulations......................:...................... 20

Study of mining conditions............................................. 20

Acknowledgments. ........................................................ 21
INTRODUCTION.

By JOSEPH A. HOLMES.

The general supervision of the work oH the coal-mine inspectors in 

New^Mexico and Indian Territory'was transferred on June 10, 1907, 

by the Secretary of the Interior to the Geological Survey in a letter 

from which the following paragraphs are extracted:

I have to request that from and including the 1st day of July, 1907, you will take 

up the practical administration of the act for the protection of the lives of miners 

in the Territories, approved March 3, 1891, and the act amendatory thereof, approved 

July 1,1902, and the supervision of the work of the coal-mine inspectors in New Mexico 

and the Indian Territory appointed pursuant to said statute, and those who may hereafter be appointed in such Territories in which the aggregate annual output, is in 

. excess of 1,000 tons of coal.

In this connection it is suggested that the officers of the Geological Survey having 

the matter in charge should not only investigate the general mining conditions in the 

Territories, .but also the nature and extent of the mine accidents, particularly those 

resulting from explosions, and report to the Department the results of such investigations. These reports should contain also suggestions as to IIOAV the mining conditions 

may be improved and accidents prevented, without undue hardship to the operators.

In a letter dated June 14, 1907, this supervision of the work of the 

coal-mine inspectors was placed by the Director of the Survey under 

the technologic branch of that organization. In endeavoring to 

carry out the suggestions of the Secretary relative to the improvement of the mining conditions and prevention of mine accidents in 

the coal mines of the Territories, a number of examinations of the 

more dangerous coal mines of the Indian Territory were made by 

Clarence Hall, Samuel Sanford, Kollin T. Chamberlin, and the expert 

in charge of the technologic branch. Other and more extended 

examinations of the coal mines of both Indian Territory (Oklahoma) 

and New Mexico have been planned. Meanwhile Mr. Hall and his 

associates have been investigating the nature, extent, causes, and 

results of a number of disastrous coal-mine explosions in several of 

the States. These studies have been carried on in connection with 

the general investigation of the waste and destruction of coal in 

mining operations.

. In connection with all these investigations, and with a view to 

determining the practicability of preventing coal-mine explosions 

and improving mining conditions, a general inquiry was begun by 

Mr. Hall, with the assistance of Walter 0. Snelling and under the
4 COAL-MINE ACCIDENTS: CAUSES AND PEEVENTION.

advice of Prof. Charles E. Munroe, concerning the nature and extent 

of such explosions and the methods employed in the United States 

or in foreign countries to prevent their occurrence.

In response to numerous requests for information on this subject, 

a brief summary of the results of these inquiries has been prepared 

for immediate publication as the present bulletin. Later bulletins 

.will deal with other phases of this subject and also embody the 

results of the investigations of coal mining and coal-mine accidents 

in the Territories.

The figures given in this rpport indicate that during the year 1906 

nearly 7,000 men were killed or injured in the coal mines of this 

country, and that the number of these accidents caused directly or 

indirectly by mine explosions has been steadily increasing. It is 

also indicated that this increase has been due in part to the lack of 

proper and enforceable mine regulations; in part to the lack of reliable information concerning the explosives used in mining, and the 

conditions under which they can be used safely in the presence of 

the gas and dust encountered in the mines; and in part to the fact 

that in the development of coal mining not only is the number of 

miners increasing, but many areas from which coal is being taken are 

.either deeper or farther from the entrance, where good ventilation is 

more difficult and the dangerous accumulations of explosive gas more 

frequent.

The increase both in the number and in the seriousness of mine 

explosions in the United States during past years may be expected 

to continue unless, through investigations made in the United States 

such as have proved effective in other coal-producing countries, information can be obtained and published concerning the explosives 

used, the conditions under which they may be used safely in the 

presence of coal dust or gas, and the general conditions which make 

for health and safety in coal-mining operations. Such information, 

obtained through comprehensive and impartial investigations, may 

serve in this, as in other countries, as an intelligent basis both for 

legislative enactments and for agreements among persons associated 

with mining operations.

One after another of these terrible underground disasters awakens 

the sympathies of the nation and arouses an earnest desire that they 

may be entirely prevented. Experience in the deeper and more dangerous coal mines of Belgium and other countries not only indicates 

that these mine accidents may be reduced to less than one-third their 

present number in the United States, but also gives promise of results 

which in the future may at least approach complete prevention.
COAL-MINE ACCIDENTS: THEIR CAUSES AND PREYENTION-A PRELIMINARY STATISTICAL REPORT.

By CLARENCE HALL and WALTER 0. SNELLING.

STATISTICS BEiLATING TO ACCIDENTS IN COAT. MIKES. 

FATAL ACCIDENTS IN THE UNITED STATES.

 »

In the coal mines of the United States in 1906, 6,861 men were 

killed or injured, the number killed being 2,061 and. the number 

injured being 4,800.

The number of men killed in the coal mines of the United States for 

each year from 1890 is shown in the following table: 

Number of men killed in the coal mines of the United States, 1890-1906.

1900............................ 1,493

1901............................ 1,594

1902............................ 1,828

1903............................ 1,794

1904............................ 1,999-

1905............................ 2,097

1890.............

1891.............

1892.............

1893.............

1894. ............

1895.............

1896 .............

1897.............

1898 .............

1899.............

............... 701

............... 1,076

............... 859

............... 965

............... 957

................ 1,057

................ 1,120

............... 947

............... 1,049

............... 1,243

1906............................ 2,061

Total...................... 22, 840

The total number of men killed since 1889, as shown above, is 

22,840. It will be noted that as many violent deaths have occurred 

in the coal mines of the United States during the last six years as 

during the preceding eleven years, the number of fatal accidents 

having practically doubled within that time.

NUMBER OF MEN KILLED FOR EACH THOUSAND EMPLOYED. 

INCREASE IN THE UNITED STATES.

The great increase in the production of coal during the last decade, 

and the related increase in the number of men employed in the 

industry, may seem to account for the increase in the number of 

fatal accidents. But the following table, giving the number of men 

killed for each 1,000 employed, shows that the increase can not be 

accounted for in this way:
o COAL-MINE ACCIDENTS: CAUSES AND PREVENTION.

Number of men killed in the coal mines of the United States for each 1,000 men employed.

1895..............

1896..............

1897..............

1898..............

1899..............

1900..............

.................. 2.67

..............:.. 2.79

................. 2.34

................. 2.59

................. 2.98

................. 3.24

1901................

1902................

1903.................

1904.................

1905 .................

1906.................

.............. 3.24

............... 3.49

.............. 3.14

.............. 3.38

.............. 3.53

.............. 3.40

DECREASE IN EUROPEAN COUNTRIES.

PROTECTIVE LEGISLATION.

In all the European coal-producing countries the output of coal has 

increased greatly during the last ten years, but the number of 

deaths per 1,000 miners, instead of increasing as in this country, has 

undergone a marked and decided decrease. This decrease has been 

due to the effect of mining legislation in those countries for 'the safeguarding and protection of the lives of the workmen, and has been 

made possible by government action in establishing testing stations 

for the study of problems relative to safety in mining, including the use 

of explosives.

0 BELGIUM.

The decrease in Belgium is shown in the following table:

Number of men killed for each 1,000 men employed in the coal mines of Belgium for each

decade since 1S30.

1831-1840.......................... 3.19

1841-1850.......................... 3.18

1851-1860.......................... 3.28

1861-1870.......................... 2. 60

1871-1880.......................... 2.36

1881-1890.......................... 1.99

1891-1900.......................... 1.39

1901-1906........................... 1.02

It will be seen from the above table that the study of mining conditions in Belgium has resulted in a reduction of the death rate per 

1,000 men employed to one-third of the ratio now existing in the 

United States. It seems certain that if a similar study of mining 

conditions were to be made in the United States and proper legislation could be secured to enforce the conditions found to be necessary 

for a better safeguarding of the lives of the miners, the death rate 

from mine accidents would be greatly reduced. The following table 

gives the death rate from accidents in the coal mines of Belgium in 

the years 1895-1906:

Number of lives lost in the coal mines of Belgium for each 1.000 men employed.

1896.................

1897.................

1898.................

1899.................

1900.................

.............. 1.16

.............. 1.03

.............. 1.04

.............. .97

.............. 1.05

1902.................

1903.................

1904.................

1905.................

1906.................

.............. 1. 07

.............. 1.14

.............. .93

Ql

.............. .94
COAL-MINE ACCIDENTS: CAUSES AND PREVENTION.

CHEAT BKITATN.

The number of men killed in the coal mines of Great Britain for 

each 1,000 men employed is shown for each year since 1890 in the 

following table:

'Number of men killed in the coal mines of Great Britain for each 1,000 men employed.

1891.. ..............

1892.................

1893................

1894.................

1895.................

1896.................

1897.................

1898.................

.............. 1.50

1 49

............... 1.55

.............. 1. 60

.............. 1.49

.............. 1.48

.............. 1. 34

.............. 1.28

1899.................

1900.................

1901.................

1902.................

1903..................

1904.................

1905.............:...

1906.................

.............. 1.26

.............. 1.30

.............. 1.36

.............. 1. 24

.............. 1.27

.............. 1.24

.............. 1.35

.............. 1.29

The number of men killed in the coal mines of Prussia for each 

1,000 men employed is shown for a number of years in the following 

table: .

Number of men killed in the coal mines of Prussia for each 1,000 men employed.

1861-1866................

1867-1880 ...............

1881-1890................

189] ......................

1892. ...... .../.. ........

1893......................

1894......................

1895......................

1896......................

......... 2.66

......... 2.94

9 Q3

......... 2.89

......... 2.21

......... 2.62

......... 2.21

......... 2.54

......... 2.58

1897'. ................

1898.................

'1 SQQ

1900.................

1901.................

1902.................

1903.................

1904.................

............... 2.35

.............. 2.86

9 Tl

.............. 2.25

.............. 2.34

.............. 1.99

.............. 1.92

.............. 1.80

In France the number of lives lost per 1,000 men employed has 

been very low for a number of years, but since the publication of 

the last available report an explosion has occurred at the Courrieres 

mine in that country, causing the death of more than 1,000 miners, 

and this would materially affect the result of any tabulation. The 

number of lives lost per 1,000 men employed for each year for which 

statistics are available is as follows:

Number of lives lost in the coal mines of France for each 1,000 men employed.

1901

1902

1903

1904

1905

1.03

.95 

.86 

.89
8 COAL-MINE ACCIDENTS: CAUSES AND PEEVENTION.

COMPARATIVE SUMMARY.

On comparing'the average death rates from accidents in coal mines 

for each 1,000 men employed in different countries the full significance of the figures already given may be seen.

In the following table, giving the average ratio for the last period 

of five years for which statistics are at hand, the position of the United 

States may be compared with that of the principal European coalproducing countries:

Number of men killed for each 1,000 men employed averages for Jive years.

France (1901-1905)............................................. 0.91

Belgium (1902-1906) . . ........................................ 1.00

Great Britain (1902-1906)....................................... 1.28

Prussia (1900-1904) . . . . . . . .................................. 2.06

United States (1902-1906) .........................i............ 3.39

Belgium maintains the most thoroughly equipped testing station 

in the world, and for a number of years has carried out extensive 

experiments to devise means to prevent accidents and to increase the 

safety of workers in the mines. The success of these experiments 

will be better realized when it is stated that at the beginning of the 

investigations the number of men killed each year for each 1,000 

men employed was 3.2, or very nearly that now shown for the United 

States, while at present it is less than one-third of that number.

Great Britain and Germany also maintain testing stations, where 

every question relating to the testing of explosives, safety lamps, 

rescue devices, and all similar matters may be submitted to experimental studies. As the result of this foresight great reductions have 

been made in the number of accidents in the coal mines of these 

countries. 

CAUSES OF MINE ACCIDENTS. 

FATAL ACCIDENTS FROM FALLS OF ROOF AND COAL.

In 1906 the causes of the fatal and nonfatal accidents in the coal 

mines of the United States were as follows:

Coal-mine accidents in the United States, 1906.

Accidents due to- Killed.

228

80

1,008

732

Injured.

307

215

1,863

2,192

It will be noted that 50 per cent of all the fatal accidents and 39 

per cent of all the nonfatal accidents were the result of falls of roof 

and coal, and that accordingly these are the most prolific source of
COAL-MINE ACCIDENTS: CAUSES AND PREVENTION. 9

 accidents in the coal mines of the United States. The following 

statement of deaths from this cause per 1,000 men employed shows 

how the United States compares with several of the foreign coal1 

producing countries in this regard:

Deaths from falls of roof and coal per 1,000 men employed.

Belgium..........:............................................ 0.40

France........................................................ .47

Great Britain.................................................. .64

Germany....................................................... .92

United States................................................... 1.70

In'all the countries mentioned, except the United States, the use 

of excessive charges of explosives is prohibited by law, and definite 

limits are set as to the amount of any explosive that may be used. 

Although these regulations were framed with the object of preventing 

gas explosions, it is believed that the}r have been of marked effect in 

preventing accidents from falls of roof and coal, as the very great disturbing and jarring effect exerted by the discharge of large amounts of 

explosives in a mine is believed to be one of the most important causes 

of falls of roof. The actual fall of the rock or coal may not occur at 

the time of firing the charge, but the heavy shots weaken the wall and 

roof and start cracks that impair the support of the rock, so that 

months after the blast, without warning, the roof or wall falls.

It is also to be noteol that explosions of fire damp and coal dust 

have a similar effect in jarring and weakening the walls and roof, and 

in gassy regions, where small explosions of fire damp are of frequent 

occurrence, falls from this cause may make up a considerable percentage of the total number. But even in such regions the use of explosives and unsatisfactory forms of lamps is generally the indirect cause 

of the fall, for nearly all explosions of fire damp are caused by ignition 

from the shots used in breaking out the coal or from naked lights used 

by the miners.

In all foreign countries from which statistics are available restrictions in the maximum amount of explosives allowed to be used have 

not only increased the safety from explosions of gas, but have also 

materially diminished the loss of life from falls of roof.

The following table shows the number of deaths per 1,000 men from 

falls of roof and coal in France for each five-year period since 1870:

Number of men killed from falls of roof and coal in France for each 1,000 men employed.

. 1871-1875...................................................... 1.26

1876-1880...................................................... .95

. 1881-1885...:.................................................. .88

1886-1890.......................'............................... .62

1891-1895...................................................... .59

1896-1900...................................................... .47
10 COAL-MINE ACCIDENTS: CAUSES AND PREVENTION.

The steady decrease in the death rate from this cause is noteworthy, and is undoubtedly due largely to the greater stability of the 

sides and roof when free from the jarring and fissuring effect of large 

charges of explosives.

In Belgium, results similar to those obtained in France have followed the reduction of the allowed charges, as will be seen from the 

following table:

Number of men killed from falls of roof and coal in Belgium for each 1,000 men employed.

1851-1860................................ 1..................... 0.998

1861-1870...................................................... .898

1871-1880........................................................ .708

1881-1890...................................................... . 6G1

. 1891-1900....................................................... .512

1901-1904...................................................... .406

In Great Britain and Germany the results are similar to those in 

France and Belgium, and thus the evidence on this subject is found 

to be consistent, and to point uniformly to the conclusions mentioned.

FATAL ACCIDENTS FROM GAS AND DUST EXPLOSIONS.

Gas and dust explosions form another important cause of mine 

accidents. In the United States during 1906 11 per cent of all the 

deaths in coal mines were due to such explosions.

In general, explosions of coal dust and fire damp are brought about 

either by ignition from explosives used in mining or from, miners' 

lamps. Both of these causey have' received careful study at the 

foreign testing stations, and the result of the legislation which has 

followed is well shown in Belgium, where gas is particularly prevalent 

in the mines, but where, through precautions resulting from the 

study of the conditions-that favor explosions,.loss of life from this 

cause has been reduced to a minimum. The following statement 

shows how successful the results in this direction have been:

Number of men killed from explosions of fire damp in Belgium for each 1,000 men

employed.

1831-1840....................... 0. 965

1841-1850....................'... .764

1851-1860....................... .428

1861-1870....................... .344

L871-1880........................ 0.487

1881-1890........................ .364

1891-1900..:..................... .208

1901-1904........................ .039

From this statement it will be seen that the number of fatal accidents resulting from the explosion of fire damp have been so greatly 

reduced that the present death rate from this cause is .but one-tenth of 

that of thirty years ago. This has been due to systematic testing of 

safety lamps, only those forms being allowed to be used which are 

capable of withstanding rapidly moving currents of fire damp under 

all conditions likely to be encountered in mines, and to thorough testing of all explosives to determine the amount of each which can be 

fired without danger of explosions of fire damp or coal dust.
COAL-MINE ACCIDENTS: CAUSES AND PREVENTION. 11

FATAL ACCIDENTS FROM OTHER CAUSES.

Other causes of fatal accidents in. coal mines, such as defective 

hoisting machinery, suffocation by carbon dioxide or poisonous gases, 

collision of coal cars, and many other causes of similar nature, are 

generally within the control of the State mine inspectors, and if a sufficient number of intelligent and capable inspectors are provided accidents of this character may be kept within ve'ry close limits without 

great difficulty.

NUMBER OF MEN KILLED FOR EACH MILLION TONS OF COAL

PRODUCED.

UNITED STATES.

When the total number of fatal accidents in the coal mines of the 

United States is considered with reference to the number of tons of 

coal produced, it is seen that the number of men killed for each million 

tons of coal produced has not changed materially in the last fifteen 

years. The following table shows the number of men killed in the 

co'al mines of the United. States for each million long tons of coal produced in each year since 1890:

Number of men killed in the coal mines of the United States for each million tons of coal

produced, by years. .

1890 ...............

1891 ...............

1892 ...............

1893 ...............

1894 ...............

1895 ...............

1896 ...............

1.897 ...............

1898 ...............

.............. 4,97

.............. 7. 14

.............. 5.36

.............. 5.93

.............. 6.28

.............. 6.13

.............. 6.53

.............. 5.30

.............. 5.34

1899 ...............

1900 ...............

1901 ...............

1902 ...............

1903 ...............

1904 ...............

1905 ...............

1906 ...............

............... 5.49

............... 6.20

............... 6.08

............... 6.79

............... 5.62

.......'........ 6.24

............... 5.97

............... 5.57

Considered in periods, the average results obtained are as follows:

Number of men killed in the coal mines of the United States for each million tons of coal

produced, by periods.

General average, 1890-1906................................... 5. 93

1890-1895..................................................... 5.97

1896-1900..................................................... 5. 77

. 1901-1906..................................................... 6. 04

It is very doubtful whether natural conditions in any other country 

in the world are so favorable as in the United States for getting out 

coal with the minimum amount of danger to the workmen employed. 

The structural relationships in the principal coal districts of the 

United States are entirely favorable, and beds of 4, 5, and 6 feet in 

thickness, lying in nearly horizontal positions and providing almost
12 COAL-MOTE ACCIDENTS: CAUSES AND PEEVENTION.

ideal conditions for mining, make up a greater proportion of the coal 

properties in active development than in any other coal-producing 

country.

The coal mines of the United States, considered as a whole, are not. 

troubled by fire damp to any greater extent than the mines of most 

other countries. The abundance and cheapness of timber in this 

country in the past should also have been factors of considerable 

importance in reducing the number of accidents in mines, inasmuch 

as with abundant timber the use of sufficient props to support the 

roof and sides would not be prevented by the factor of cost.

But in spite of all the natural conditions tending to reduce the 

percentage of mine accidents in the United States to a low figure, 

the accidents during the last fifteen years show directly contrary 

results. Considered in regard to the number of deaths per 1,000 

men employed, the United States, as has already been pointed out, 

occupies a less favorable position than any other of the coal-producing countries, more than three times as many men out of .each 1,000 

employed being killed as in some of the European countries that are 

much less favored in natural conditions. In regard to deaths per 

million tons of coal the United States not only occupies a position 

worse than that of most of the European countries, but is also showing an increase in the rate, whereas every other country is showing 

a decrease.

EUROPEAN COUNTRIES.

The following statement shows the figures for Great Britain:

Number of men killed in the coal mines of Great Britain for each million tons of coal

produced.

. 1874-1883................. l...................................... 7.42

1884-1893....................................................... 5.65

1894-1903............................:.......................... 4.70

1904............................................................ 4.41

1905...........................................................; 4.64

1906............................................................ 4.31

For France the figures are as follows:

Number of men killed in the coal mines of France for each million tons of coal produced.

5.55 

5.21 

4.80- 

4.20 

4.55 

4.17

For Belgium, which is troubled with fire damp to a greater extent 

than any other coal-producing country, the figures are not so good as
COAL-MINE ACCIDENTS: CAUSES AND PBEVENTION. 13

those just given for France; but even in Belgium better results have 

been obtained for the three years 1904-1906 than in the United States, 

as will be seen from the following table:

Number of men killed in the coal mine's of Belgium for each million tons of coal produced.

1.895. ......................... :.................................. 7. 70

1896............................................................ 6. 39

1897............................................................ 5.77

1898:............................................................. 7. 78

1899........................;.............................,..... 5.77

1900............................................................ 5. 96

1901................................. : .......................... 6. 93

1902............................................................ 6. 29

1903............................................................ 6. 68

1904............................................................ 5. 66

1905............................................................ 5. 64

1906.........-................................................... 4. 96

Prussia shows -less favorable results than the United States in 

regard to lives lost per million tons of coal, yet during the last ten 

years there has-been an almost steady decrease in the number killed 

per million tons mined, and the number of-lives lost per 1,000 men 

employed has also decreased from 2.54 to 1.80, showing that the high 

death rate based on amount of coal produced is largely due to the 

natural conditions existing in the coal mines of that country..

CONCLUSIONS.

It has already been stated that in no country in the world are the 

natural conditions so favorable for the safe extraction of coal as in 

the United States, and it has also been pointed out that in spite of 

tills fact the number of lives lost per 1,000 men employed is far higher 

than in any other coal-producing country, and that the number of 

lives lost per million tons of coal produced is exceeded by only one 

other country. It now remains to be shown that unless energetic 

means are taken to counteract this prevailing tendency not only will 

the death rate in proportion to men employed and tons produced 

increase as it has done in the last few years, but it will increase at a 

much more rapid rate.

With the depletion of the thicker and more favorably mined 

seams of coal, thinner and less regular seams must be worked. This 

factor will undoubtedly be of the greatest importance within a comparatively few years, and the natural result would be to greatly 

increase the death rate. The rising price of timber will have the 

effect of decreasing the number of wooden props used in mining, and 

probably will increase the chance of accidents from falls of roof and 

coal. Another important factor in the mines of the United States is to 

be found in the nationality of the miners. Most of the men are foreign
14 COAL-MINE ACCIDENTS: CAUSES AND PREVENTION.

born, a large proportion of -them are unable to understand English 

freely, and a still larger number are unable to read or write that 

language. Some of them are inexperienced and do not take proper 

precautions either for their own safety or for the safety of others. 

This becomes a most serious menace unless they are restrained by 

carefully enforced regulations.

With the mining of the smaller beds of coal and the gradual development of properties worked with more difficulty, bringing the mining 

conditions in the United States more nearly to a position of equality 

with those abroad, a great increase in the number of accidents must 

be expected unless proper steps are taken -to remedy the conditions 

that have brought about the present remarkably high death rate in 

the coal mines of the United States. '

PREVENTION OF MINE ACCIDENTS.

The successful results which have attended efforts made in European coal-producing countries to reduce the dangers of coal mining 

have already been mentioned. The most important of the means 

through which these results have been achieved, in the opinion of 

the investigators who have had the matter in charge, .will now be 

considered and some of the regulations governing coal-mine operations in foreign countries will be briefly discussed. No mention is 

made herein of many of the admirable precautions taken in some of 

the foreign mining districts for combating unfavorable local conditions, and many regulations, such as those in regard to timbering, 

spacing of pillars, and width of rooms and entries, will be taken up in 

a later paper.

SAFETY LAMPS.

The compulsory use of safety lamps in mines having a dangerous 

amount of fire damp is general in all the European coal-producing 

countries. The regulations on this subject for Great Britain are as 

follows: a

RULE 8. No lamp or light other than a locked safety lamp shall be allowed or used 

(a) in any place in a mine in which there is likely to be any such quantity of inflammable gas as to render the use of naked lights dangerous; or (6) in any working place 

approaching near a place in which there is likely to be an accumulation of inflammable gas.

And when it is necessary to work the coal in any part of a ventilating district with 

safety lamps, it shall not be allowable to work the coal with naked lights in another 

part of the same ventilating district, situated between the place where such lamps are 

being used and the return airway.

RULE 9. Whenever safety lamps are used, they shall be so constructed that they 

may be safely carried against the air current ordinarily prevailing in that part of the 

mine in which the Hmps are for the time being in use, even though such current should 

be inflammable.

a Coal-mines regulation act, 1887, paragraph 49,
COAL-MINE ACCIDENTS: CAUSES AND PREVENTION. 15

The laws of. the other coal-producing countries are similar in essential particulars to those of Great Britain.

The keeping of at least two safety lamps in all mines (whether 

thought to be gaseous or not) is also required in some countries; and 

laws regulating the manner of locking safety lamps and requiring that 

all lamps shall be capable of being so locked by magnetic devices, 

compressed air, or other means, as not to be opened by any unauthorized person, are also in effect. -?

The employment of relighting stations, at which locked safety lamps 

may be relighted in the mine when they are accidentally extinguished, 

is permitted in several countries. In the coal-mines regulation act of 

Great Britain, rule 10, it is stated that relighting stations must not be 

in the return air from any part of the mine in which safety lamps are 

required to be used, the object of this provision being to prevent the 

possibility of fire damp being ignited at the relighting station and 

passing back to the workings.^ In Belgium and Germany the lamps 

in use are equipped with relighting devices of approved design, and 

are known to be practically free from danger of igniting fire damp, so 

that relighting stations are unnecessary.

Provisions regarding the examination of safety lamps at regular 

intervals by some competent person, to see that they are kept in safe 

condition, and regulations forbidding the possession by any unauthorized person of any contrivance for opening the lock 'of any safety 

lamp are also generally in force in France, Belgium, Germany, and 

Great Britain.

USE OF EXPLOSIVES.

The various commissions which have been appointed by Great 

Britain, France, Germany, and Belgium for the study of mining conditions have brought out the fact, thoroughly proved by experiment 

and by actual tests in mines, that certain types of explosives are much 

more liable than others to ignite fire damp and thus to cause gas explosions. This is true whether we consider (1) a test based on equal 

weights of the two explosives or (2) the fairer test of such weights of 

each as have equally powerful effects.

Accordingly, in all the European coal-producing countries, regulations have been made forbidding the use of such explosives as are 

known to be most dangerous in this'respect, in all mines in which fire 

damp is liable to be present to a dangerous'extent, and requiring the 

use in these mines of such explosives as have been proved to be 

reasonably free from the clanger of igniting explosive-gas mixtures.

The order regulating the use of explosives in Great Britain contains 

the following provisions:

(a) In all coal mines in which, inflammable gas has been found within the previous 

three months in such quantity as to be indicative of danger no explosive, other than a 

permitted explosive as hereinafter defined, shall be used in or taken for the purpose of
16 COAL-MINE ACCIDENTS: CAUSES AND PREVENTION.

use into the seam or seams in which the gas has been found or any shaft or drift communicating therewith which is in process of being deepened or sunk, or being driven, 

as the case may be.

(6) In all coal mines which are not naturally wet throughout no explosive, other than 

a permitted explosive as hereinafter defined, .shall be used in or taken for the purpose 

of use into any road or any dry and dusty part of the mine, or any shaft or drift communicating therewith, which is in process of being deepened or sunk, or being driven, 

as the case may be. v

The "permitted explosh%s" to which reference is made are those 

explosives which have been found, after testing at the Government 

experiment station, to be capable of being fired in an explosive-gas 

mixture without causing the ignition of the gas. A "list of permitted explosives" is kept, including all those explosives that answer 

the required test, and all explosives used in mines that are dangerous 

because of gas or coal dust must be selected from this permitted list, 

which now includes more than fifty explosives.

Similar restrictions in the use of unsafe explosives were enforced in 

Great Britain in the coal-mines regulation act of 1887, and control of 

like kind is exercised in France, Belgium, and Germany. In all these 

countries the restriction of unsafe explosives has caused the development of "safety" explosives, which have proved greatly superior to 

those previously in use. The stimulating effect that the restriction 

of the more dangerous types of explosives has had on the invention 

and testing of safety explosives is well shown by the number of safety 

explosives devised each year. These explosives are as satisfactory 

in every respect as the common powder previously in use, and yet are 

free from most of the danger of causing mine explosions, inseparably 

connected with the use of the older explosives. Several of the newer 

explosives, for example, have been found to be incapable of igniting 

an explosive mixture of fire damp and air, even when the charge of the 

explosive is 700'grams; whereas as little as 30 grams of the older 

explosives would invariably cause an explosion of fire damp.

In Belgium, owing to the greater amount of fire damp present in the 

mines of that county, a further restriction, known as the charge limit, 

has also been put in force. Through this restriction the maximum 

amount of any explosive which is allowed to be used in any single 

charge is defined. The actual amount allowed varies according to the 

relative liability of the explosive'to ignite fire damp, but with all the 

better class of explosives it is well above the amount needed for use in 

a single charge under proper mining conditions.

These restrictions in the kind and amount of explosives have yielded 

an additional benefit in the fact that the reduction in the amount used 

not only reduces the number of accidents, but also to a large degree 

prevents coal waste. The miner finds that with the restricted amount 

of explosive allowed it is necessary to mine by machine or hand in 

order that the explosive may produce the coal, and a larger per cent 

of lump coal is consequently produced. He also finds that the props
COAL-MINE ACCIDENTS: CAUSES AND' PREVENTION. 17

for supporting the roof can be set closer to the face of the workings, 

the smaller amount of explosive being less liable to knock them down. 

The miner in this manner secures greater protection through the 

increased support of the roof.

The importance of this work in regard to the prevention of accidents from explosives has been well summarized by V. Watteyne, 

chief engineer of the administration of mines, Belgium, as follows:

The use of explosives is, and especially was, the principal cause of danger of explosion in the mines. It is this cause which, previous to.1890, before the generalization 

of safety explosives and before the use of explosives of every description had been 

reduced by various means to a minimum, brought about deadly catastrophes.' Within 

the decennial period 1880-1889 the number of victims of ignitions caused "by the use 

of explosives reached 90 per cent of the total number of victims of explosions in mines.

It may be asked, What is the reason for such a preponderance, considering that the 

number of lights introduced into the mine by the lighting apparatus is far greater than 

the number of shots? It would be too long to examine here in detail the causes of the

greatest danger of explosives, but we will mention the principal ones in a few words. 

On one hand the safety lamp, though still imperfect, has acquired a fair degree of 

safety; on the other hand, the flame of a lamp, even when uncovered, can not ignite a 

fire-damp mixture unless its proportion of fire damp be very high, say 6£ to 7 per cent, 

a proportion which the aspect of the flame betrays in a very apparent manner a long 

time before; nor can it ignite a mixture of dust. The case is different with the violent flames caused by the explosion of charges, for these are not only liable, by the 

shock they produce in the atmosphere of the workings, to call forth to the dangerous 

point an unexpected rush of fire damp, but they can ignite the clouds of dust which 

this very commotion has raised, and in this way can bring about terrible catastrophes, 

while in consequence of the apparent absence of fire damp one may think himself 

nearly safe.

The endeavors made after 1887, in consequence of disastrous explosions, to reduce 

the danger of explosives have brought about a very sensible reduction of the number 

of the victims of blasting. Thus within the following decennial period, from 1890 to 

1899, in spite of the awful accident of Anderlues, which, in 1892, made 160 victims, 

the total number of men killed by mining explosions in Belgium has been reduced to 

258, from the previous figure of 455, the proportions of victims of ignition by the use 

of explosives having fallen to 23 per cent.

In connection with the foregoing statement the following table will 

prove of interest, showing the remarkable increase in the use of safety 

powder in Belgium during ten years, coincident with, the decrease in 

the use of black blasting powder for the same period.

Use of safety explosives and black blasting powder in the coal mines of Belgium.

Year.

1895. ............................................................................

1897 ............................................................................

1899. ............................................................................

1901.............................................................................

1903. . ..............................................................:............

Safety 

explosives,

Kilograms. 

80, 786

128, 870

176,440

247.849

399,821

Black powder.

Kilograms. 

089, 344

557, 900

405, 648

442, 780

4.15, 292

It should be further noted that the black powder was restricted to 

mines not containing fire damp. 

20992 Bull. 333 07 2
18 COAL-MINE ACCIDENTS: CAUSES AND PREVENTION. 

STORAGE OF EXPLOSIVES.

Regulations governing the storage of explosives for use in coal 

mines are in general effect in European coal-producing countries, and 

provide that no explosive substance shall be stored in the mine, that 

no explosive shall be taken into a mine except in canisters containing 

not more than 5 pounds, and that no unused powder shall be left in a 

mine over night. The amount of powder in the possession of a workman at any one time is also limited, and the amount which can be 

taken into a mine is usually restricted to that which will be used in one

smft- '

' SHOT FIRERS.

Regulations enforced in Great Britain provide that in all mines in 

which inflammable gas is present or has been found in dangerous 

quantities within the previous three months all charges of explosives 

shall be fired by a competent person, termed a shot firer. The object 

is to place responsibility in the hands of men better qualified for the 

work than the average miner. The shot firer begins his work after the 

miners have left for the day, each miner before leaving having prepared a number of holes in such places as he wishes charges to be fired. 

The shot firer charges the holes with explosive and tamps and fires the 

charges.

It will be seen that by this method the charges are fired at a time 

when but few men are in the mine, and that accordingly, if a firedamp explosion occurs, fewer lives are lost than if the miner fired the 

shots at a time when other miners were in the workings.

Still another factor of greater importance is that the shot firer, 

through constant experience, soon becomes used to the proper use of 

explosives, and also learns to charge the holes and fire them in the 

safest way possible. The shot firer is also free from the temptation to

use excessive charges in the desire to get out a great amount of coal 

with the least possible effort. It is well known to all persons experienced in coal mining that overcharging of holes and mining by 

means of large shots fired in the solid mass of the coal bring about 

many fire-damp and coal-dust explosions,

At the present time several electrical shot-firing devices are being 

tested, with some promise of effecting a considerable saving of life. 

The main principle of these devices is the firing of the charges one 

after another at proper time intervals. As already stated, the firing of 

the charges takes place after the miners have left for the day, and the 

entire operation of the devices is automatic. It is of course necessary, 

after the charges are fired, to have some one examine each room in 

which a shot has been fired to see that conditions are normal, and that 

no feeders of gas have been ignited which might start a mine lire. The 

use of shot-firing devices or some other means equally safe is required 

by regulation in Great Britain.
GOAL-MINE ACCIDENTS: CAUSES AND PREVENTION. 19 

MATERIALS USED FOR TAMPING.

The use of drill dust, slack coal, or other inflammable material for 

tamping is forbidden in European coal-producing countries, it having 

been found that gas and coal-dust explosions are more likely to occur 

when such materials are used. The laws of Great Britain compel the 

use of clay or like substance for tamping. The material is delivered to 

the miner near the working place.

WATERED ZONES.

The watering of the sides and roof of coal-mine passageways has been 

found to- be of material benefit in preventing local ignitions of coal 

dust from becoming general. The watering prevents the coal dust 

from being stirred up by a small explosion, and the reduction in the 

explosive properties of the wet coal dust has the general effect of preventing an explosion from traveling into other workings. As dust 

explosions gain in. destructive effect the farther they travel, it is believed that the thorough watering of zones greatly reduces the destructive effect of such explosions.

The watering is effected by means of sprinkling or spraying devices 

of various kinds. Specially constructed nozzles are in use, particularly in Germany, which produce a fine spray or mist by. means of 

water under pressure, so that the air is thoroughly moistened.

An English commission has lately pointed out that sprinkling may 

produce a local weakening of the walls in some places, and the possibility of a slight increase in falls must accordingly be weighed against 

the advantages given by the protection from dust explosions.

AID TO THE INJURED.

The mining regulations of Germany, France, and Belgium require 

that mines shall be supplied with means for administering to the 

comfort of injured workmen and that proper appliances shall be provided for first aid.

Rescue devices equipped with small tanks of compressed air or 

compressed oxygen, or with some chemical appliance for generating' 

a supply of oxygen, so as to enable a person to enter mine workings in 

which an irrespirable atmosphere is present, are required in some 

countries. By the aid of such apparatus rescue parties may enter the 

mine workings immediately after a fire-damp disaster and rescue injured miners, who would otherwise soon fall victims to the poisonous 

atmosphere surrounding them. Mine fires started by the ignition of 

feeders of fire damp may be brought under control much more easily 

when immediate efforts are made to combat them by men equipped 

with rescue devices.
20 COAL-MINE ACCIDENT'S: CAUSES AND PREVENTION. 

ENFORCEMENT OF REGULATIONS.'

In all European countries the enforcement of regulations in regard 

to coal-mine operations is placed in the hands of specially appointed 

officers or mine inspectors familiar with the industry and able to 

examine mining conditions intelligently and see that the mining laws 

are obeyed. 4 To insure compliance with the regulations, penalties are provided 

in case of noncompliance, and these penalties fall on the. miner or 

the operator, or both, according to the nature of the violation. An 

injunction restraining the further operation of a mine until the. laws 

have been obeyed is a further means in the hands of the mine in-, 

spector for insuring the enforcement of .the law when the step is 

found necessary.

STUDY OF MINING CONDITIONS.

England, Germany, and Belgium maintain experiment stations 

where explosives are tested and where safety lamps, rescue appliances, 

and all other devices for use in mines may be examined. In France 

similar work is done by commissions which are appointed from time 

to time, and in other European countries there are permanent stations. It has alreacty been pointed out in this paper that concurrently with the establishment of the experiment station, mine conditions begin to show the improvement that is so marked a feature of 

the statistics here presented. Safety lamps greatly superior to those 

previously in use were manufactured as soon as the defects of the 

earlier forms were pointed out at the experiment stations, and the 

development of improved forms of rescue appliances, electrical firing 

devices, and many other means of giving increased safety to mine 

workers have been inseparably connected with the stimulus given by 

these stations.

Inventors have been encouraged by the knowledge that the actual 

merits of an}7 improvement they might make could be determined 

at the testing station, and at the same time mine owners have been 

able to see the results of thorough tests of all new devices, and to 

choose types of safety lamps, rescue appliances, and other devices, 

with a full knowledge of their working under actual mining conditions.

The experiments thus made have been of general benefit, and, 

aside from reducing the death rate from accidents in mines to a very 

low figure, they have been the means of bringing about improvements in operation that have been a substantial advantage to both 

mine workers and mine owners.
COAL-MINE ACCIDENTS: CAUSES AND PREVENTION. 21

ACKNOWLEDGMENTS.

The statistics relating to mine accidents in the United States for 

the years 1905 and .1906 are taken from "The production of coal in 

1906," by E. W. Parker, of the United States -Geological Survey. 

The statistics relating to mine accidents in the United States for a 

number of years previous to 1905 are derived from tables prepared 

by F. L. Hoffman, expert mining statistician, and printed in the 

fifteenth annual report of the Tennessee mining department.

Acknowledgments are due to Mr. William Cameron, United States 

mine inspector for Indian Territory, Mr. Jo. E. Sheridan, United 

States mine inspector for New Mexico, and many other State mine 

inspectors, for numerous favors and suggestions received during the 

writers' visit to the mining districts under their supervision; also 

to Capt. J. H. Thompson, chief inspector of explosives of Great Britain, and to Mr. V. Watteyne, chief engineer of the administration of 

mines, Belgium, for many kind favors extended during the recent 

visit to foreign testing stations.

The statistics of mine accidents in Belgium are taken from "Ann ales 

des mines de Belgique" or from "Les lampes de surete et les explosifs," by V. Watteyne. The figures stated for France are from "Statistique de 1'industrie minerale en France et en Algerie." The'statistics for Prussia are from the "Zeitschrift fur das Berg-, Hiitten-, 

imd Salinen-Wesen irn preussischen Staate." The statistics for Great 

Britain were taken from "General reports and statistics, mines and 

quarries." The tables relating to accidents from falls of rock and 

coal are mainly from "Der Verhandhmgen und Untersuchungen. der 

Preussischen Stein- und Kohlenfall Commission;" and some general 

statistics of mine accidents were also.obtained from that work.

The general excellence of the European reports is especially noteworthy, and the complete and careful classifications adopted by 

them have greatly assisted in the preparation of this report.

CLASSIFICATION OF THE PUBLICATIONS QF THE UNITED STATES GEOLOGICAL

SURVEY.

[Bulletin No. 383.]

The publications of the United States Geological Survey consist of (1) Annual 

Reports, (2) Monographs, (3) Professional Papers, (4) Bulletins, (5) Mineral 

Resources^ (6) Water-Supply and Irrigation Papers, (7) Topographic Atlas of United 

States folios and separate sheets thereof, (8) Geologic Atlas of the United States 

folios thereof. The classes numbered 2, 7, and 8 are sold at cost of publication; the 

others are distributed free. A circular giving complete lists can be had on application.

Mostof the above publications can be obtained or consulted in the following ways:

1. A limited number are delivered to the Director of the Survey, from whom they 

can be obtained, free of charge (except classes 2, 7, and 8), on application.

2. A certain- number are delivered to Senators and Representatives in Congress 

for distribution.

3. Other copies are deposited with the Superintendent of Documents, Washington, 

D. C., from whom they can be had at prices slightly above cost.

4. Copies of all Government-publications are furnished to the principal public 

libraries in the large cities throughout the United States, where they can be consulted 

by those interested.

The Professional Papers, Bulletins, and Water-Supply Papers treat of a variety of 

subjects, and the total number issued is large. They have therefore been classified 

into the following series: A, Economic geology; B, Descriptive geology; C, Systematic geology and paleontology; D, Petrography and mineralogy; E, Chemistry and 

physics; F, Geography; G, Miscellaneous; H, Forestry; 1, Irrigation; J, Water storage; K, Pumping water; JL, Quality of water; M, General hydrographic investigations; N, Water power; 0, Underground waters; P, Hydrographic progress reports, 

Q, Fuels; R, Structural materials. This paper is the seventh in Series Q, the complete list of which follows (PP=Professional Paper; B=Bulletin):

SERIES Q, FUELS. .

B 263. Preliminary report of the operations of the coal-testing plant of the United States Geological 

Survey at the Louisiana Purchase Exposition, St. Louis, Mo., 1904; E. W. Parker, J. A.Holmes, 

M. R. Campbell, committee in.charge. 1905. 172pp.

PP4S. Report on the operations of the coal-testing plant of the United Slates Geological Survey at the 

Louisiana Purchase Exposition, St. Louis, Mo., 1904; E. \V. Parker, J. A. Holmes, M. R. Campbell, committee in charge! 1906. 3 parts. 1,492 pp., 13 pis.

B 290. Preliminary report on the operations of the fuel-testing plant of the United States Geological 

Survey at St. Louis, Mo., 1905, by J. A. Holmes. 1906. 240 pp. - . B 323. Experimental work conducted in the chemical laboratory of the United States fuel-testing 

plant at St. Louis, Mo., January 1, 1905, to July 31, 1906, by N. W. Lord. 1907. 49 pp.

B 325. A study of four hundred steaming tests made at the fuel-testing plant, St. Louis, Mo., in 1904, 

1905, and 1906,'by L. P. Breckenridge, 1907. 196 pp.

B 332. Report of the United States fuel-testing plant at St. Louis, Mo., January 1, 1906, to July 1,1907, 

J. A. Holmes, in charge. 1908. pp.

B 333. Coal-mine accidents: Their causes and prevention; a preliminary statistical report, by 

Clarence Hall and W. 0. Snelling. 1907. 21 pp.

Correspondence should be addressed to

THE-DIRECTOR,

UNITED STATES GEOLOGICAL SURVEY,

WASHINGTON, D. C. 

. DECEMBER, 1907.

o