The Value Representations used for Private Data Elements shall be the same as those VRs specified for Standard Data Elements in Section 6.2. The encoding shall conform to the requirements for those VRs and shall be in accordance with the negotiated Transfer Syntax. A Private Data Element with SQ VR (a Private Data Sequence) may include Items with both Standard and Private Data Elements. Standard Data Elements used within a Private Data Sequence shall use the VRs as defined in PS 3.6 for those data elements.
The semantics of Standard Data Elements within a Private Data Sequence, and the definition of Attribute Values, are implementation dependent.
For a Standard Extended SOP Class the Attributes (07FE,0010) Pixel Data, (5400,1010) Waveform Data, and (60xx,3000) Overlay Data shall not be included within a Private Sequence Item, nor within a standard Sequence Item nested directly or indirectly within a Private Sequence Item.