Numbers Refer to Number of Persons Involved



1951-72

U.S.A.

1959-72

CAN.

U.S.A.

1973

CAN.



Terrain



Rock

1131

99

90

2



Snow

594

95

32

3



River

4

0

1

0



Unknown 

2

2

8

0



Ascent or Descent



Ascent

848

115

80

1



Descent

767

73

38

4



Unknown 

116

8

13

0



Immediate Cause



Fall or slip on rock

612

53

63

2



Failure of piton or nut

41

2

12

0



Falling rock or object

155

27

8

0



Failure of rappel

78

3

2

0



Slip on snow or ice

233

27

9

1



Fall into crevasse

32

11

3

0



Loss of control — Voluntary



glissade

67

5

2

1



Avalanche

113

38

3

0



Lightning

31

3

0

0



Skiing

6

3

0

0



Faulty use of crampons

10

1

1

1



Exceed abilities

120

5

1

0



Exposure and/or Exhaustion 

88

2

9

0



Heat prostration

3

0

0

0



Failure to follow route

4

0

2

0



Stranded

91

11

2

0



Illness Medical (incl. Pulm.



Edema and Frostbite)

33

3

10

0



Prussik knot slipped

2

0

1

0



Unknown

12

2

6

0



Contributory Causes



Climbing unroped

459

43

11

1



Climbing alone

132

14

7

0



Exceeding abilities



(inexperienced)

410

57

34

1



Darkness

43

3

0

0



Inadequate equipment

188

16

2

0



Old rope

8

1

0

0



Piton or nut failure

46

3

6

1





1951-72

1959-72



1973





U.S.A.

CAN.

U.S.A.

CAN.



Bad weather

72

7

9

0



Exposure and/or Exhaustion

36

1

15

0



Party separated

34

6

2

0



Age of Individuals











Boys

5

0

} 1

0



Under 15

63

4







15-20 

603

42

45

1



21-25 

392

38

30

3



26-30 

203

45

14

0



31-35 

114

16

5

0



36-50 

} 182

} 27

4

0



Over 50





1

0



Unknown 

169

24

31

1



Affiliation with Climbing Groups

Unaffiliated

592

37

35

2



Affiliated

600

106

36

1



Unknown 

529

53

60

2



Estimate of Experience

None or little

806

71

41

2



Moderate

455

47

37

1



Experienced

278

60

34

2



Unknown 

192

18

19

0



Month of Year

January

54

2

9

1



February

89

12

4

0



March

89

3

6

0



April

99

3

2

0



May

150

11

15

0



June

201

31

21

0



July

314

65

28

2



August

314

55

14

2



September

174

7

16

0



October

94

3

6

0



November

76

1

3

0



December

57

1

7

0



Unknown 

8

2

0

0