The BACnet Information Model is identified by the following URI:

http://opcfoundation.org/UA/BACnet_V2/

Documentation for the NamespaceUri can be found here.

The NodeSet associated with this version of specification can be found here:

https://reference.opcfoundation.org/nodesets/?u=http://opcfoundation.org/UA/BACnet_V2/&v=2.00.1&i=1

The NodeSet associated with the latest version of the specification can be found here:

https://reference.opcfoundation.org/nodesets/?u=http://opcfoundation.org/UA/BACnet_V2/&i=1

" https://reference.opcfoundation.org/nodesets/?u=http://opcfoundation.org/UA/BACnet_V2/&i=1

Supplementary files for the BACnet Information Model can be found here:

https://reference.opcfoundation.org/nodesets/?u=http://opcfoundation.org/UA/BACnet_V2/&v=2.00.1&i=2

The files associated with the latest version of the specification can be found here:

https://reference.opcfoundation.org/nodesets/?u=http://opcfoundation.org/UA/BACnet_V2/&i=2