What kind of question are you using when you ask someone ""How long have you been in this field of work?""

The type of question that is mentioned above is "Days / Time period related questions".

Explanation:

Question is nothing but an interrogative expression that usually used to test or explicit information from others. There are various types of questions such as Dichotomous Question (Yes or No type of question), Multiple choice question, Wh question etc. Now having a look at the above provided question "How long have you been in this field of work", we can clearly see that this question is put forth to explicit information like the number of days he has been working in that field.

And the answer for that question will be like, "I am here in this field for the past 3 years" where "3 years" is the key answer for this question and hence we can say that it is a "Days? Time period related question.