It's not necessarily your responsibility to restrict the use - your customers will need to evaluate whether your product meets their needs. Materials must be evaluated for their specific application so even if you do some basic testing, it may not be sufficient or applicable to what your customers are doing. The material itself may be acceptable but depending on your processing/sourcing/certification, they may not be able to use you as a supplier for higher risk applications. However, if you know your product is not suitable for certain uses (eg, if you know that it is not stable after being irradiated or steam sterilized), you should provide that info.
You will need to be prepared to provide your customers with a lot of information (source materials, traceability, sub-suppliers, etc). For some applications they will expect full traceability to your sources. Depending on the criticality of the material, you may end up being a crucial supplier and need to be audited. Strong purchasing controls and the ability to demonstrate that the product is consistently meeting spec is key.
Speaking from the other side, I have run into lots of struggles with suppliers who say they support "medical device" use but are uncooperative and won't give us the documentation needed to actually be compliant. Of course that's their prerogative as a business, but it wastes everyone's time. State upfront what you can and can't do, and let us manufacturers figure out whether it will work for us.