| The cause and number of coal mining fatal accidents has been recorded since state mine inspection offices began in the mid 1870's. With the advent of the United States Bureau of Mines, coal mine fatalities were analyzed in various ways. This study looks at the data from a novel direction: the relationship between fatality incidence rates and how long a mine has been active. Data from 1991 to 2000 was extracted from both the MSHA fatality reports and the MSHA Address/Employment database. The binomial proportion statistical test was used to determine when deaths exceeded or fell below the expected number of deaths based on the proportion of mine workers for various years of active life.; To obtain reliable statistical results, there must be a minimum number of data point for both variables. For the current study the variables are the number of fatalities and the number of mine employees in a single year. There were insufficient data for assess fatalities at independent preparation plants and surface mine, so only underground coal mining fatalities were analyzed. (Abstract shortened by UMI.)... |
