Here's the website for the UK Health and Safety Executive.
http://www.hse.gov.uk/statistics/industry/index.htm
There are not so many people mining, and there are ridiculously strict regulations around mining. (I used to build, inspect, test 'chock interface units' which can be thought of as 'active walking pit props'. A cutting head removes a long stretch of coal, which falls onto a conveyor. That new section needs to be pit-propped, so this first line walks forward with the cutting head.)
Farming has many accidents - busy people, lots of opportunity for accident. Also a high rate of suicide. (Again, access to means and methods. Farmers are one of the small number of people allowed to own guns in the UK.)
It would be interesting to see the number of deaths per 1,000 workers for each sector, to try and get a better comparison.