To what extent do you remind non-respondents of the musculoskeletal symptom survey?

I am asking this question because of non-respondents to the musculoskeletal symptom survey.

Even though I posted the initial announcement and reminded you one more time before the deadline, there are still quite a few people who haven't signed up yet.

Since working hours vary at the site, it is difficult to tell if they missed the notice or simply assumed it did not apply.

I feel like contacting each person individually would be too burdensome, but I am also concerned that simply closing the matter might make it look like an omission.

In cases like this, how many times do you usually remind them?

I am curious whether you tend to share the matter with the department head if there are no respondents after the deadline, or if the person in charge contacts them individually.