Additional information for employee

We are construction and engineering company. We have four different service lines (Materials testing, Geotechnical, Environmental and facilities). Each of these services has sub services under it. In addition to assigning people to organization and location, we need to assign our employee to service lines and sub services. An employee can be assigned to multiple sub services. For e.g., an employee in California office, can be assigned to Environmental service line but need to assigned to Asbestos, Industry Hygiene sub services.

Have you done similar type of setup in Oracle EBS HR? Where do you suggest storing this type of information?