The following clarification to this policy is provided to address differences in the equipment of at least one manufacturer...

The intent of the guidance included in OBM bulletin #4 was to address the electronic aspect of noise reduction headsets. Apparently some noise reduction headsets, specifically those manufactured by BoseŽ, are capable of having the noise reduction electronics turned off. In this mode, the headphone is converted to serving as non-electronic hearing protection equipment instead of electronic noise reduction equipment. Passengers are allowed to wear non-electronic hearing protection during all phases of flight.