Table 1.

Questionnaire.

Variable	Dimension	Item	Measurement item
Workload	Work time	I1	To what extent can I determine my daily work time based on my work schedule?
		I2	To what extent can I meet my physiological requirements every day, except for work?
	Work demand	I3	To what extent do your current jobs require you to work hard?
		I4	To what extent do you have a lot of tasks to do in your current job?
		I5	To what extent do you have insufficient time to do your work?
		I6	To what extent do you have excess tasks to fulfill in your current job?
		I7	To what extent do you think there is not enough time to complete the work?
		I8	To what extent do you face conflicts from a variety of different job requirements?
Job satisfaction	–	I9	I am satisfied with the nature of the work I am doing
		I10	I am satisfied with my superiors (who directly instructed me to work)
		I11	I am satisfied with the relationship with the workers I work with
		I12	I am satisfied with my work income
		I13	I am satisfied with the promotion opportunities I can get at work
		I14	Considering every aspect of my work, I am satisfied with my current work situation
Miners’ unsafe state	–	I15	I can't work normally because of the bad environment (climate parameter) underground
		I16	When the body is tired or sick, I will keep working
		I17	I sometimes start working with emotions (affected by family relationships, death of relatives, etc.)
		I18	Before work, I occasionally use drinking to relieve the unhappiness at work
		I19	I think the relevant safety professional knowledge is enough to solve the problems at work
		I20	At work, I sometimes try to save trouble and do not strictly abide by the safety rules and regulations
		I21	At work, I sometimes maintain the safety protection device according to my own habits
		I22	At work, I sometimes use my hands instead of prescribed tools to operate