lide Systems Options


Original Equipment Manufacturers (OEMs) and specifiers of metal halide lighting
systems should be aware that changes to the 2005 National Electrical Code (NEC) will impact
manufacturers of metal halide luminaires as well as their customers. While these changes have
not yet been published, the process to modify the NEC to incorporate these provisions is
sufficiently far along that the NEMA Lighting Systems Division believes some initial
communication on this matter is advisable to OEMs and specifiers. As more information
becomes available, further updates will be provided. It is also expected that additional
information will be published in the form of papers and articles targeted at various lighting
audiences.

National Electrical Code Background

The NEC is administered by the National Fire Protection Association (NFPA) and is
revised via an open consensus process every three years. The current 2002 NEC is now
undergoing many changes as the result of submitted proposals by stakeholders of all types. A
newly revised version, including any changed requirements, will be published as the 2005 NEC
in the fall of 2004. Municipalities or states are then able to adopt and enforce the most recent
edition of the Code if they so desire. Once adopted, electrical inspectors will apply the
requirements of the new 2005 edition of the NEC when they are involved in the inspection
processtypically for new construction or when an existing building undergoes a renovation
that would require an electrical permit and resulting inspection.

Important Changes in the 2005 NEC for Metal Halide Systems

This information bulletin focuses on one key change that is anticipated to be approved for
the 2005 NEC. Specifically, the 2005 NEC will require that luminaires that use a metal halide
lamp shall be provided with either a containment barrier that encloses the lamp (historically
referred to as an enclosed luminaire) or shall be provided with a means, typically a special
lampholder, that will only accept an ANSI Type O metal halide lamp. (Exceptionthis
requirement will not apply to open luminaires with thick-glass parabolic reflector PAR lamps.)

The intent of this requirement is to require that, when open luminaires are specified in the
future, only Type O lamps will operate in those luminaires. This means that for those

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LSD
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jurisdictions that adopt the 2005 NEC, the historically common Type S lamp will not be an
option for open luminaires in future new construction or in major lighting renovations to existing
buildings.

Implications of this 2005 NEC Change

Existing installations that use open luminaires and Type S lamps will continue to exist,
even in municipalities that adopt the 2005 NEC. Type S metal halide lamps will continue to be
available for those customers that wish to continue to use them in existing open luminaires and
in accordance with appropriate lamp and luminaire manufacturer warnings and instructions.

Existing open luminaires will accommodate Type O lamps without a lampholder
change. Existing enclosed luminaires will accommodate Type O, S, or E lamps without a
lampholder change.

It is expected over time that the mix of metal halide lamps available will naturally shift to
reflect the anticipated adoption of the 2005 NEC and that there will be an associated shift to
luminaires that are either enclosed or that only accept Type O lamps.

When operated in accordance with manufacturers warnings and instructions, open
luminaires with Type- S lamps remain a safe and effective lighting alternative for many
applications. However, when warnings and instructions are not heeded, the operation of an open
luminaire with a Type S lamp may potentially present an elevated level of risk of fire (in some
applications) that would not exist with lighting systems employing either an enclosed luminaire
or an open luminaire with a Type O lamp.

NEMA lamp and luminaire manufacturers support this change to the 2005 NEC code
since it will simplify the metal halide systems options available and will also reduce the potential
risks associated with failure to properly follow the warnings and instructions for systems that
specify open luminaires with Type S lamps.

For more information regarding the proper use of Type - O, S, and E metal halide
systems please refer to the NEMA white paper on this subject that is freely available at
www.nema.org
:

LSD 25- 2000, Best Practices for Metal Halide Systems, Plus Questions and Answers
about Lamp Ruptures in Metal Halide Lighting Systems. (Note: Currently under revision
to include information presented in this bulletin.)




For further information, contact Ron Runkles at 703-841-3278.
July 23, 2004