Law or rules (internatinal) on salary of personnel working in the field of Petroleum, Paints, pesticides, etc?

I am currently working in the field of Fuel ie Petroleum. I heard that there is some international law or rules regarding the salary of the people who works in the field of Fuel, paints, pesticides, etc being hazadarous working place and contidion is there any regulations os mimimum requirement for such fields?? I would be highly help ful because my office asked such documents so that mysalary will be increased. any link web sites, national government official employment websites, etc will be helpful for me... pls help.