A product spec defines an end-item-requirement, i.e. what you want when all is said and done. It should define all physical installation interfaces, all functional interfaces & operation, and specify how those interfaces and operations are tested. It should NOT define how the product in made.
Process spec is the ultimate "how-to" spec and is the opposite of a Product Spec.
BOM lists all the parts that make up an assembly. A Product Spec does not have a BOM. A Product Spec may require the use of certain part(s) if that is essential to the end item functionality, but the balance of the parts should not be so defined.
The Product Spec should completely define how the product is inspected and tested.
MIL-STD-961...although what I've posted here is general and in no way unique to military procurement.
These all dovetail with my own understanding and expectations.
A little more background on the situation.....
I am currently working with an employer whose major business in the importing of a wide variety of products for resale in the US market. The company has been in business for a VERY long time....but has just recently decided to bring its QA/QC processes into the 20th century (no, that's not a typo).
Product "specifications" is left up to the suppliers. They essentially tell us what they are selling us. heretofore, it has been up to the supplier to provide as much (or little) detail in their specification as they deem appropriate. Management has now embarked on a project of trying to "tighten" this situation by requesting specific pieces of information. The overall goal -- according to management -- is to "make sure we are getting from our suppliers what we ordered". In my estimation, the types of information being requested straddles across the boundaries of product spec, process spec and a BOM. A form has been developed for this purpose. But, due to the wide variety of products dealt with, it is difficult to have "one size fits all" solution. The result is a single form that is hodge-podge amalgamation of all three....with differing amounts of information and detail for different products....and the decision of what types of information are required being made 'ad-hoc' by whomever deals with that specific product. To make matters worse, the document is then suppied to a third party service to perform product inspections.
I have been involved in some rather intense "philosophical" discussions with management over this issue. I'm trying to come up with a fresh way of conceptualizing the problem so that -- hopefully
-- a fresh solution will preseent itself.
Insight, suggestions, or tales of previous experiences appreciated.....