The previous answers include some totally accurate statements and some complete rubbish. This is what the NHS website states:
" It is not possible to catch shingles from someone else with the condition. The shingles virus is reactivated from a previous infection with the varicella-zoster virus (the virus that causes chickenpox) and is not transmitted by person-to-person contact.
However, it is possible for someone who has never had chickenpox to catch chickenpox from someone with shingles. In the UK, chickenpox is so common during childhood that 9 out of 10 adults have had it, so will not be affected".
Click through the links ('Symptoms', 'Causes', etc) to get a thorough understanding of the condition.
I've had shingles myself, and I've known many other people who've had it. If I was an employer I would instantly dismiss any employee who failed to come into work because of the illness. (It's perfectly possible to work through the pain, as I did, and the risks to others are negligible).
Chris