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COMMISSION
  
OF
  
INQUIRY
  
INTO
  
SAFETY
  
AND
  
HEALTH
  
IN
  
THE
  
MINING
  
INDUSTRY 
 
25 
 
TABLE 7 
MOST SIGNIFICANT ACCIDENT TYPES IN GOLD MINING 
 
 
TYPE 
OF 
MINE 
 INJURED 
 KILLED 
 TOTAL 
 
 
 
 
Nr. %   
Nr. %   
Nr. % 
 
Rock 
falls 
& 
  2272 
30,8 
 263 
61,7 
 2535 
32,5 
Rockbursts 
 
Transport 
& 
  1578 
21,4 
 54 
12,7 
 1632 
21,0 
Mining 
Cumulative 
  3850 
52,2 
 317 
74,4 
 4167 
53,5 
 
Fall 
of 
material  962 
13,1 
 11 
2,6 
 973 
12,5 
& Rolling Rock 
Cumulative 
  4812 
65,3 
 328 
77,0 
 5140 
66,0 
 
Falling 
In/From  650 
8,8 
 28 
6,6 
 678 
8,7 
Slipping & Falling 
Cumulative  
 
5462 74,1  
356  83,6  
5818 74,7 
 
Manual 
handling 
of 
 967 
13,1 
 2 0,5 
 969 
12,4 
Material/Mineral 
Cumulative  
 
6429 87,2  
358  84,1  
6787 87,1 
 
TOTAL   7368 
100,0 
 426 
100,0 
 7794 
100,0 
 
 
The next major category in the table is headed “Transport and Mining”.  The GME’s 
tabulation present these under 12 headings that are all related to moving mining equipment 
and transport.  This category is responsible for 20,9% of all accidents causing bodily injury.  
In view of the scattered nature of deep level mining operations (a medium to large operation 
mine will have 5 000 to 10 000 m of stope face) this large percentage is perhaps not 
surprising. 
 
The remainder of data in Table 7 reveals that a large number of mishaps relate to events 
such as “fall of material”, “rolling rock”, “manual handling of material, falling in / from” 
and “slipping and falling”.  These incidents account for an unusually high proportion 
(33,6%) of all injuries. No details are available as no one gave evidence directly related to 
accidents.  One can only speculate, therefore, that many of these accidents are regarded by 
management as those where the victim is to be blamed, because of his carelessness, lack of 
attention etc.  It is probably true that under ideal conditions most of these events could be 
avoided by those present.  However, their frequent occurrence suggests that this is not a 
satisfactory explanation. 
 
 
Management should do everything possible to minimise the possibility of such occurrences.  
In addition they should provide sufficient training so that the men on the spot can recognise 
the hazards and know how to take appropriate steps to avoid them. 
 

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COMMISSION
  
OF
  
INQUIRY
  
INTO
  
SAFETY
  
AND
  
HEALTH
  
IN
  
THE
  
MINING
  
INDUSTRY 
 
26 
 
3.2.2  Technological Background to the Accident Records 
 
The disappointingly high rates of fatalities and injuries, 1,54 killed and 25,82 injured 
(reportable injuries only) per 1 000 exposed to risk underground, represents a tragic picture. 
 
It is important to examine the background to this performance and attempt to identify the 
remedies so that the situation can be improved.  These rates do not agree with the rates 
given in the Chamber of Mines submission (p 42).  The difference is probably attributable 
to a difference in the denominator of the rate formula.  In these figures the number at risk is 
taken as the number employed underground, which according to the Minerals Bureau 
records was 269 466 in 1993. 
 
Fundamentally, the combination of three physical factors and a human problem make the 
South African gold mining industry unique.  The physical factors are: great mining depth, 
brittle and abrasive rocks and the often narrow width of mineralisation.  The human 
problem will be discussed in Chapter 3.3, as it tends to affect all branches of mining. 
 
-Depth of Mining. 
 
According to the GME’s records, the maximum mining depths in the Orange Free State, in 
the PWV (Gauteng) Region and in the Western Transvaal are 3 511 m, 3 940 m and 3 140 
m respectively.  The major gold mines are working at depths that are unusually great by 
international standards.  Depth below surface determines the virgin rock temperature, that is 
rock temperature free of mining influence, and the pre-mining rock pressures.  Both rock 
temperature and rock pressure increases approximately linearly with depth.  The rate of 
increase is determined by the temperature gradient and rock density, respectively. 
 
High rock temperature has both direct and indirect effects.  The direct hazards are heat 
stroke and heat exhaustion.  Accident statistics reveal that in 1993 these heat sicknesses 
were responsible for 5 deaths and 17 reportable injuries.  These data indicate that the hazard 
is barely under control.  The less direct, but perhaps more pervasive effect of heat is that it 
undermines a person’s vigilance and effectiveness in both mental and physical exertions. 
 
Due to the higher rock density, a depth of 3 km in rock produces the same pressure that a 
submarine would experience at a depth of about 8 km.  High rock pressure promotes rock 
fracture, which can be either gradual or sudden and violent.  Frequent sudden rock failures, 
as with underground explosions, are the most insidious hazards that miners have to face.  
There is an obvious correlation between the great depth of mining and the shockingly high 
accident rate in gold mines.  (see Chapter 3.2.4) 
 
-Brittle and Abrasive Rocks. 
 
The failure of hard brittle rocks tends to occur suddenly and often with great violence.  This 
feature of rocks surrounding gold reefs contributes greatly to the high frequency of seismic 
events experienced in gold circles.  It should be noted that mines operating in soft rocks do 
not, as a rule, experience rockbursts of the type observed in hard and brittle rocks. 
 
Hardness and abrasiveness of quartzite have been major factors in retarding the 
development of mining methods that do not use explosives to break the ground.  Lack of 
development in this direction has hampered the modernisation of the gold industry in South 
Africa for several decades. 

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