Our business has been divided into groups, people who can work from home are to do so.
Admittance into the building by essential externals only with advance notice and a declaration of previous travel approved.
Groups are expected to keep to the group while in-office. Staggered groups for breaks, clocking in & out, no mingling of groups in the canteen etc.
So if an entire section of the employees have to self-isolate, others will hopefully be unaffected.
It decreases 'leanness' and flexibility, but at least it's hoped things can keep running.
Surfaces are cleaned repeatedly during the day with alcohol.
Spacing between workspaces is enforced, using the space created by remote workers + placing work desks / machinery further apart.