Industry Relations & Standards
Document No.:
Revision No.:
Issue Date:
DQ4-144-067
E
09-08-2006
Subject: Warning – Metal Halide Display/Optic Lamps [HMI, HMD, HMP, HSD, HSR, HTI, HCD]
Please verify that you have the latest revision prior to use. Do not use if outdated.
H/Warnings/OSRAM/MHID.doc
Printed on: 9/29/2006 9:21:00 AM
Page 4 of 6
Display/Optic metal halide lamps may only be used in the operating positions described in the
OSRAM SYLVANIA product catalog. Please note that lamp photometric values and arc stability
can be effected by the operating position.
OZONE GENERATION:
•
During operation, Display/Optic metal halide lamps produce a spectrum that ranges from
about 150 nm in the ultraviolet region to the infrared region.
•
If the quartz glass bulb is transparent in the ultraviolet region between 180 and 220 nm, this
short-wave radiation will convert a small quantity of atmospheric oxygen (O
2
) surrounding the
lamp into ozone (O
3
). Moreover, the oxygen molecules will link together with the nitrogen
(N
2
) in the air, creating nitrogen oxides (NO
x
). (Some believe that the smell attributed to
ozone is in actuality from the nitrogen oxides.)
•
Ozone gas is toxic when inhaled in high concentrations over long periods of time. Ozone
levels can be measured and monitored with commercial measuring equipment. Always keep
ozone levels below the applicable TLV (threshold limit value).
•
An "ozone smell" (or smell of nitrogen oxide) may be detected shortly after ignition. There
are two probable causes for this condition. O
3
and NO
x
production is caused by the (short-
duration) radiation of the spark gap used for lamp ignition. Or, the cold condition of the
quartz glass bulb has slightly shifted its UV-absorption characteristics thus permitting a small
amount of radiation in the very short-wave ultraviolet range to be emitted by the bulb.
Typically, after the lamp has run up to its operating temperature range, virtually no ozone is
produced by the lamp, as a rule, due to the quartz glass absorption and the self-absorption of
the plasma
.
LAMP COOLING:
1.
All Display/Optic metal halide lamp bases must be kept below 230ºC (446ºF) during operation
to prevent premature lamp failure. If convection cooling is inadequate, forced air-cooling may
be used. Please see OSRAM literature for cooling requirements of specific lamp types.
2.
If forced air-cooling is used, care must be taken to direct airflow at the bases only. Striking
elsewhere on the lamp with the airflow will result in poor lamp performance or premature
failure.
3.
Discoloration, surface pitting, and/or corrosion of the lamp connections indicate a thermal
overload. To obtain optimum lamp performance, components exhibiting these conditions must
be cleaned or replaced.
LAMP REMOVAL:
•
Turn off power to the lamp and allow lamp to cool (forced or convection) for a minimum of 30
minutes prior to shutting main fixture power and opening fixture. Do not remove lamp until it
has cooled.
•
Lamps should be placed in their original OSRAM SYLVANIA packaging for temporary
storage until disposal and/or transportation to a disposal location. See “Lamp Transportation”
and “Lamp Disposal” sections below for relevant information.
