Just a word from the Antipodes...
Here in Tasmania we used to use "lots" of SOX lamps, mostly 90 and 135 watt ones made by Philips or G.E.C.
They were used over Zebra Crossings and to light the yards of Tasmanian Hospitals and Aged Care facilities, however compared to the UK, with SOX lamps all along its motorways and in suburbs, our use was feeble. Older lamps, such as SLI and SO types are exceedingly rare here.
In the early 1990s the Hydro Electric Commission (now broken up into Aurora Energy, Transend and H.E.C. Power), trialled SOX-18s in some surburban streets in Howrah, Hobart. They were in Philips Kombi Luminares. They never took off, but you still occasionly see SOX-18s as security lights.
In Melbourne, in the suburb of Brunswick, Philips SOX180s used to be used in trough like luminares slung on wires over Sydney Road. They used to swing about in the beeze, how the sodium never splattered all over the electrodes is mystery.
Almost all of these are gone now, all replaced by SON, elliptical bulb with a diffusing coating, can be used in the same fitting as mercury lamps, but require different control gear. 2/ SON / HPS lamps.">SON-T, tubular clear hard glass for floodlighting. 3/ SON-TD, tubular double ended clear quartz, the length and cap are equivalent to those of tungsten halogen lamps.">high pressure sodium lamps in Sylvania Optispan Luminares. A few SOX 90s still hang on at the rear of what was the Douglas Parker Rehabilitation Centre, in Tower Road, New Town, these are the last Low Pressure Sodium Lamps in Service in Tasmania.
There also used to be SLI-H Linear lamps in the sodaberg anode room at the Comalco Bell Bay Aluminium Smelter at the northern end of the Island, but they are probably long gone. I saw them in 1987.