STONE OPERATOR 

MINING FACTS–2008

DEPARTMENT OF HEALTH AND HUMAN SERVICES 

Centers for Disease Control and Prevention 

National Institute for Occupational Safety and Health 

March 2011

Mining Operations 

In 2008, a total of 4,633 stone mining operations reported 

employment to the Mine Safety and Health 

Administration (MSHA).1 Stone mines comprised 31.1% 

of all mining operations. 

Mines producing the primary commodity of 

limestone (crushed and broken) comprised the largest 

number of operations (n=2,046; 44.2%). 

Stone mining operations were located in all states 

and territories except Delaware. 

Pennsylvania had the most stone mines (n=394; 

8.5%), followed by Texas (n=360; 7.8%). 

Employees 

A total of 78,975 employees,2 corresponding to 76,749 

full-time equivalent (FTE)3 employees, were reported to 

MSHA by stone mine operators. 

Within the mining sectors,4 stone mine operator 

employees accounted for 22.5% of all employee 

hours reported. 

Stone operator employee hours were reported for 

both underground (2.6%) and surface (97.4%) work 

locations.5

0

50

100

150

200

250

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 Number of Employee Hours (millions) Coal Operator Metal Operator Nonmetal Operator Stone Operator Sand & Gravel Oper Coal Contractor Noncoal Contractor

Fatalities 

There were seven occupational fatalities among stone 

mine operator employees in 2008, compared to eight in 

2007. 

The stone mine operator fatality rate was 10.6 [95% 

confidence interval (CI): 4.3, 21.9] fatalities per 

100,000 FTE employees. 

0

2

4

6

8

10

12

14

16

18

20

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 Number of Occupational Fatalities

Underground Surface

Nonfatal Lost-time Injuries 

There were 1,626 nonfatal lost-time injuries (33 at 

underground and 1,593 at surface work locations) among 

stone operator employees occurring at an overall rate of 

2.5 [CI: 2.4, 2.6] injuries per 100 FTE employees. A total 

of 75,970 days lost from work6 resulted from these 

injuries, comprising 19.9% of days lost across all mining 

sectors. 

The nonfatal lost-time injury rate was 1.6 [CI: 1.1, 

2.3] for underground and 2.5 [CI: 2.4, 2.6] per 100 

FTE for surface work locations. 

The most frequent classification of nonfatal lost-time 

injuries for stone operator employees involved 

handling materials (n=571; 35.1%). 

Sprains and strains were the most frequently 

reported nature of injury (n=772; 47.5%).

The back was the most frequently reported body part 

injured (n=282, 17.3%) and accounted for 11,936 

days lost from work. 

Distribution of Nonfatal Lost-time Injuries by Accident Class, 2008 (N=1,626)

35.1%

10.3%

12.2%

24.4%

9.8%

8.2%

Handling materials

Slip or fall of person

Hand tools Machinery

Powered haulage

All other

Sum of percentages may not equal 

100% due to independent rounding. 

Note: "Fall of ground" includes MSHA's Accident/Injury/Illness class for fall of face, rib, pillar, side, or highwall; fall of 

roof, back, or brow; and machinery cases when the source of injury was caving rock, coal, ore, or waste.
Mine and Employment Characteristics, 2008

1 2 3 Commodity and Number of Mining Operations Number of Employees Number of FTE Employees

Type of Employer Underground Surface Total Underground Surface Total Underground Surface Total 

Coal Operator 665 1,464 2,129 40,370 49,685 90,055 45,866 54,312 100,178

Metal Operator 105 188 293 5,844 33,282 39,126 5,842 34,840 40,682

Nonmetal Operator 44 676 720 2,579 20,454 23,033 2,725 20,534 23,260

Stone Operator 111 4,522 4,633 1,875 77,100 78,975 2,029 74,720 76,749

Sand and Gravel Operator NA 7,132 7,132 NA 42,307 42,307 NA 33,343 33,343

Operator Total 925 13,982 14,907 50,668 222,828 273,496 56,462 217,750 274,212

Number of Companies

Coal Contractor NA NA 3,467 6,262 37,510 43,772 4,105 22,216 26,321

Noncoal Contractor NA NA 6,128 2,992 72,459 75,451 1,998 38,088 40,086

Contractor Total NA NA 9,595 9,254 109,969 119,223 6,103 60,304 66,407

TOTAL 59,922 332,797 392,719 62,565 278,054 340,620

Commodity and 

Type of Employer

Coal Operator 12 26.2 6 11.9 18 18.7 2,103 4.6 768 1.5 2,871 3.0

Metal Operator 3 NC 2 NC 5 13.8 163 2.8 649 2.1 812 2.2

Nonmetal Operator 1 NC 1 NC 2 NC 95 3.5 412 2.4 507 2.5

Stone Operator 1 NC 6 9.4 7 10.6 33 1.6 1,593 2.5 1,626 2.5

Sand and Gravel Operator NA NA 3 NC 3 NC NA NA 550 1.9 550 1.9

Operator Total 17 30.1 18 9.4 35 14.2 2,394 4.2 3,972 2.1 6,366 2.6

Coal Contractor 3 NC 9 43.4 12 48.3 168 4.1 313 1.5 481 1.9

Noncoal Contractor 0 NC 5 13.9 5 13.2 38 1.9 463 1.3 501 1.3

Contractor Total 3 NC 14 24.7 17 27.1 206 3.4 776 1.4 982 1.6

TOTAL 20 32.0 32 12.9 52 16.8 2,600 4.2 4,748 1.9 7,348 2.4

Mining Occupational Fatalities and Injuries, 2008

Total Underground Surface Total

Nonfatal Lost-time Injuries (per 100 FTE employees)

Rate Rate No. Rate No. Rate No. Rate 

Occupational Fatalities (per 100,000 FTE employees)

Underground Surface

 No. No. Rate No.

NA Not applicable. NC Not calculated when N is less than 5. 95% CI for rates reported on reverse side. Totals may not sum due to independent rounding. 

Data source: Publicly released employment and accident/injury/illness data collected by MSHA under 30 CFR 50. 

Notes: All analyses of accident data exclude office employees. Occupational fatalities exclude all cases under 17 years of age. Further 

statistical methodology is available on the NIOSH Internet [http://www.cdc.gov/niosh/mining/statistics/method.htm]. Caution should be 

used when interpreting rates based on a small number of events. 

1Mines at which only independent contractors were working and did not show any employment were not counted. 

2Average number of employees working at individual mines during calendar quarters of active operations (includes office workers). 

3

Full-time equivalent employees computed using reported employee hours (2,000 hours = 1 FTE). 

4Mining sectors include coal operators, metal operators, nonmetal operators, stone operators, sand and gravel operators, coal contractors, 

 and noncoal contractors. 

5

Surface work locations include surface operations at underground mines, surface operations (strip or open pit), dredge, other surface 

 operations, independent shops and yards, and mills or preparation plants. 

6

Includes actual days away from work and/or days of restricted work activity. For permanently disabling injuries only, statutory days 

 charged by MSHA were used if they exceeded the total lost workdays. 

To receive documents or other information about 

occupational safety and health topics, contact NIOSH at 

Telephone: 1–800–CDC–INFO (1–800–232–4636) 

TTY: 1–888–232–6348

E-mail: cdcinfo@cdc.gov

or visit the NIOSH Web site at www.cdc.gov/niosh. 

DHHS (NIOSH) Publication No. 2011–166