This is a good question and one we have not answered in a long time.
There is no specific exemption from Service Contract Labor Standards (see FAR subpart 22.10). However, most of these contracts predominantly use a skill mix of professional employees. See the definition of professional employees at FAR 22.1102. You will see at FAR 22.1101 that the Service Contract Act of 1965, now codified in 41 U.S.C chapter 67, does NOT cover bona fide executive, administrative, and professional employees. Note: the DFARS does not implement or supplement FAR subpart 22.11.
See FAR 22.001 where it states that executive and administrative employees are defined in 29 CFR part 541.
So, you will have to determine if under your R&D contract the scope requires offerors to utilize labor categories for which FAR subpart 22.10 does apply. Don't forget to check all of the exceptions within that subpart for applicability.
Additionally, if you have more specific questions you can always reach out to your service components Labor Advisor. A list of all Agency Labor Advisors can be found at SAM.gov.