High-pressure sodium vapor lamps for open and enclosed luminaires. : Lamp survival factor: 95 % after 16,000 h burning time. Lamp maintenance factor: ≥ 80 % after 16,000 h burning time (according to DIN 13201). Service lifetime: 4 years (at approx. 11 h/day). Dimmable on conventional control gears and electronic control gears. : Very high luminous efficacy. Very good luminous flux maintenance throughout the life of the lamp. Energy savings of up to 50 % when replacing mercury vapor lamps (HQL). Optimum energy efficiency on POWERTRONIC® PTo 3DIM ECGs. : Streets. Outdoor lighting. Industrial installations. Suitable for use in open and enclosed luminaires. Outdoor applications only in suitable luminaires. : Disconnect mains before installation.. Must not be used if outer bulb is defective.. Protect from spray water..