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Polymeric Lenses

We have recently been advised by the supplier for the polymeric lenses used on some Juno Lighting Group products that these lenses will no longer be offered as "Metal Halide Lamp Containment Barriers", and that the UL listing has been discontinued at their request.

Existing Juno Lighting Group products installed with these types of lenses can be operated as long as the maintenance guidelines as specified by the lamp manufacturer are followed:

  • Metal Halide lamps must be turned off at least once per week for 15 minutes.
  • Fixtures should be relamped at, or before the end of rated lamp life. Allowing lamps to operate until they fail is not advised and may increase the possibility of inner arc tube rupture.
  • These maintenance practices will greatly reduce the likelihood of a non-passive end of life.

For future operation when replacement of the lamp is required, it is recommended that lamps with an "0" code be used. These lamps have a built-in protective containment barrier and can be used in open or enclosed luminaires.

Additionally we have been informed that NEMA has been advised of this issue and the decision was made to create a task force consisting of representatives from the lamp manufacturers and manufacturers of MH Luminaires to address specific lamps used in conjunction with the lamp containment barrier. Part of this project would include UL involvement to review the current standard and associated test methods.

If you have any questions or comments, please contact the Juno Lighting Group Technical Services Department at 888-387-2212 or by email at