Hi Robert, we do use 110V CTE on UK building sites for portable lighting & power tools.
Supply is from a 240/110 Centre tapped earth transformer. These transformers are typically portable units of 2 to 3 KVA with a standard 13A BS1363 plug on the supply cord & BSEN 60309 16A 110V (yellow) sockets on the transformer. Larger building sites have non-portable transformers hard wired in various locations throughout the site, usually on each level. The larger units have both 16A & 32A sockets to cater for heavier loads.
The plugs used are BSEN 60309-2 (formerly known as BS4343) type, colour coded yellow. The US 5-15 plug is never used, it would not be considered robust enough for site use.
I'm sure Paul may be able to provide a link to a site where you could view these transformers.
Hope this helps. David