Normally, security requirements are specified, the optional employee working in each area, dress to suit the job, such as employees in the best floor area must wear shoes sneaker heels.
Typically, the security requirements are identified for their employees working in each area, dress appropriately for the job. For example, in the production area must wear shoes. But it is not like the staff in the lab coat is required whenever laboratory.
Usually based on security policies are supplied to the staff in each area dress to suit the job. Such as employees in the field will have to wear boots and shoes.