The standard number is unclear, but an unrelated ISO/IEC TR 18001 already exists, which may result in a renumbering of the ‘18001’ standard.
The work will be carried out by PC 283 - OH&S Management systems - Requirements. PC stands for Project Committee (typically a Technical Committee is used eg TC 176 for ISO 9001). The Secretary will be BSI and the first meeting of PC 283 will be held on 21-25 October in London.
Thanks to IRCA's Inform enewsletter for this interesting snippet.