EAM Maintenance BOM

I understand that a Bill of Materials are assigned at Activity level - does anyone know of anything at Standard Operation Level?

I have a requirement for a customer to carry out an activity, but that activity could be made up of a combination of operations, for which there could be multiple material requirements.  I'm trying to automate as much as possible but can only see the functionality to have a BOM per activity, not at the lower level of Standard Op.

the method currently adopted by the business has an initial inspection with 15 different types of follow up work - of which there could be a combination of to 5 of these follow up types.  they current;y add these as bill items in their current system and each of these bill items have a number of materials associated with them.  I had hoped to create a single WO with Activity, add in the Standard Operations - which would hopefully have Materials associated with them.