In article ,
jim writes:
The TLC catalog

http://www.tlc-direct.co.uk/Products/QLFRD50W.html

shows (lower middle of page) only 4 LV Halogen lamps as suitable for
LV fire rated downlighters - ie compliant with the latest Bld Reg.

Apparently the lamps need to be dichroic, with an Al reflector and a
clear flat front lens so that heat & light are reflected forwards.

Is it correct that these are the only options?

No, lamps are either dichroic, or Al reflector.
This fitting would appear to require Al reflector, to
reflect the heat out of the front. These are now quite
difficult to find in 12V versions (they used to be much
more common).

Dichroic dump most of the heat out the back, and
presumably this fitting isn't designed to cope with that.
I could imagine it might trigger the intumescent fire seal.

A Web search brought up Philips Masterline ES Energy Saver & Osram
Decostar 51 Energy Saver dichroic, but neither appears to hold itself
out as being for fire rated downlighters.

Not suitable for this fitting.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]