What holidays do offices/clinics typically observe?

I recently got a job offer at a busy cardiology clinic to be their CT nurse for the 64-slice. The manager said they are closed holidays, but since I have never worked in a clinic, I am not aware of which holidays clinics are usually closed.
I would assume all of the nationally government recognized holidays. New years day, MLK day, Memorial Day, July 4th, Labor Day, Thanksgiving Day, and Christmas.

The 'big six' are usually observed: New Years day, Memorial Day, Independence Day, Labor Day, Thanksgiving, and Christmas. If the office/clinic observes other holidays, count it as an even bigger plus.

I worked in a community health center that observed:New Years DayMLK DayGood FridayMemorial DayIndependence DayLabor Day2 days at ThanksgivingChristmas EveChristmas DayI never complained about that. If it's a private business, they can choose to stay open or not as they wish, though, so just because this place did it, doesn't mean they all will.

Quote from ElvishI worked in a community health center that observed:New Years DayMLK DayGood FridayMemorial DayIndependence DayLabor Day2 days at ThanksgivingChristmas EveChristmas DayI never complained about that. If it's a private business, they can choose to stay open or not as they wish, though, so just because this place did it, doesn't mean they all will.

What's a 64-slice?!

The clinic where I work is "closed" on bank holidays, meaning for some of them there is a nurse there to answer the phone, and do other things that we might not have time for other days.

Quote from roser13What's a 64-slice?!