Updated 15-IX-2003
Mercury Vapour
Mercury Pressure
Mercury Spectrum
Lamp Nomenclature
Timeline of Developments
Mercury Vapour
J.T. Way
Küch and Retschinsky
MA Medium Pressure
MB High Pressure
MC Low Pressure
MD Water-Cooled
ME Super Pressure
UHP Ultra High Pressure
Mercury Vapour
Fluorescent Coated Lamps
Tungsten Ballasted Lamps
Lamp Electrodes
Additives to the Arc
Electrodeless Designs
Future Developments
Mercury Vapour
High Pressure Circuits
Low Pressure Circuits
Electronic Operation

Mercury Lamp Nomenclature

During the 1930's most of the world's countries introduced their own comprehensive systems of nomenclature to identify the many different kinds of mercury lamps which had become available. Generally these are based on logical code letter systems but in North America, lamps are assigned completely random letters to identify each type. Some of the more commonly encountered systems are disclosed in the tables below. In all cases, more than one letter may be selected from the Third Part to denote special features of the lamp.

British & French System (also Australia, Northern Europe, India, Hong Kong, Africa, Middle East)

First Part Second Part Third Part Final Parts
M Mercury A Medium Pressure C Cadmium additive -R Reflector shape
B High Pressure D Deluxe colour -G Spherical shape
C Low Pressure F Fluorescent bulb -T Tubular shape
D Water-Cooled I Iodide additives -L Linear double ended
E Short Arc L Laboratory lamp
M Coal mine service
SD Super-deluxe colour /V Vertical cap up
T Tungsten Ballasted /D Vertical cap down
U UV Suntanning lamp /H Horizontal
W UV Woods glass bulb /U Universal

Dutch System

First Part Second Part Third Part Final Part
H Mercury O Ordinary Pressure L Luminescent bulb -N New phosphor (YVO4)
P High Pressure W UV Woods glass bulb -C Comfort phosphor
I Iodide Additives
R Reflector bulb
B Spherical bulb
ML Mercury blended L Luminescent bulb
R Reflector bulb
U UV Sun-tanning bulb
W UV Woods glass bulb
CS Compact Source I Iodide Additives
SP Super Pressure P Pulsed Operation

German System

First Part Second Part Third Part Final Part
H Mercury G Glass arc tube A Clear outer bulb -R Reflector bulb
Q Quartz long arc L Luminescent bulb -B Spherical bulb
B Quartz short arc V UV Woods glass bulb
M Quartz medium arc S Silberweiß / cool white
N Low Pressure G Goldweiß / warm white
W Tungsten ballasted D Deluxeweiß / deluxe
SD Super deluxe
I Iodide additives
O For optical projection

Russian System

First Part Second Part Third Part Final Part
D Discharge lamp R Mercury L Fluorescent bulb Z Reflector shape
t Self Ballasted I Metal Halide T Tubular shape
O Horticultural SH Spherical arc tube
LH Long Arc
UV Ultraviolet

Czech & Slovakian Systems

First Part Second Part Third Part Final Part
R Mercury Rtutova V High Pr. Vysokotlaká C Clear Bulb Ciry -G Germanate phosphor
L Fluorescent Luminofor -B Halophosphate bilá
Y Yellow GlassZlut -X Vanadate phosphor
U Blacklight
K UV for Suntanning
R Reflector Reflektor
I Metal halide Iodure
M Blue/Indium Modra
Z Green / Thallium Zelena
F Iron Iodide Fe
G Gallium Iodide Ga

Hungarian System

First Part Second Part Third Part Final Part
H Mercury G High Pressure LI Luminescent S Internal starter
MI Metal Halide F Fluorescent


First Part Second Part Third Part Final Part
L High Pressure R Mercury F Fluorescent R Reflector
I Iodide
MIX Mercury blended


First Part Second Part Third Part (Wattage) Final Part
H Mercury lamp F Fluorescent ellipsoidal 40W -X Deluxe phosphor
FG Fluorescent spherical 50W -BL Blacklight UV bulb
BH Mercury self-ballasted FR Fluorescent reflector 100W -UV UV & visible output
G Clear spherical bulb 175W
R Clear reflector bulb 200W
T Clear tubular bulb 250W
K Cold atmosphere lamp 300W