Đèn huỳnh quang là loại chủ yếu được sử dụng trong các không gian thương mại và công nghiệp tại Mỹ là tương đối hiệu quả, có cuộc sống đèn dài, và có sẵn trong nhiều phong cách. Chân bốn T-12 đèn là đèn huỳnh quang phổ biến nhất được sử dụng trong các văn phòng ngày nay, nhưng họ đang được nhanh chóng thay thế bởi T-10 và T-8 đèn. | Fluorescent Lamps are the predominant type used in commercial and industrial spaces in the . They are relatively efficient have long lamp lives and are available in a variety of styles. The four foot T-12 lamp is the most common fluorescent lamp used in offices today but they are being rapidly replaced by T-10 and T-8 lamps. Energy efficient T-8 lamps are more expensive than the T-12 lamps however they provide 98 as much light and use about 40 less energy when installed with an electronic ballast. Electronic Ballasts - When replacing standard fluorescents with the more energy efficient T-8s it is necessary to replace the existing electromagnetic ballasts with the electronic ballasts which operate at higher frequencies and convert power to light more efficiently. Energy saving electromagnetic ballasts can cut fluorescent lighting energy consumption by as much as 10 . The life of these ballasts is approximately twice that of their conventional counterparts. High Intensity Discharge HID refers to lighting provided by mercury vapor metal halide and high-pressure sodium lamps. Although originally designed for outdoor and industrial uses HIDs are also used in offices and other indoor application. The principal advantage of mercury vapor HID lamps is their long life although they are only slightly more efficient than incandescent lamps. Reflectors - Highly polished retrofit reflectors are being marketed for use with existing luminaries light fixtures and can achieve a 50 reduction per fixture. Installing reflectors in most luminaries can improve its efficiency because light leaving the lamp is more likely to reflect off interior walls and exit the luminaire. Although the luminaire efficiency is improved the overall light output from each is likely to be reduced which will result in reduced light levels. To ensure acceptable performance from reflectors measure before and after light levels at various locations in the room to determine adequacy. Lighting Controls - .
