Norman Lamps, Inc.

T5 fluorescent tubes represent the most advanced and efficient linear fluorescent technology, featuring a slim 5/8-inch diameter that allows for sleeker fixture designs while delivering higher light output per watt than T8 or T12 tubes. The smaller diameter, combined with optimized phosphor coatings and higher operating temperatures, makes T5 tubes the preferred choice for new high-performance commercial installations, indirect lighting systems, and applications where maximum efficiency and light quality matter.

T5 tubes come in two distinct performance categories: T5 High Output (T5 HO) for applications requiring maximum light output, and T5 High Efficiency (T5 HE) for applications prioritizing maximum efficacy and energy savings. T5 HO tubes produce significantly more lumens per foot than T8 tubes, making them ideal for high-bay applications, indirect lighting that bounces light off ceilings, and anywhere you need substantial illumination from fewer fixtures. T5 HE tubes sacrifice some light output for better efficiency, working well for general commercial lighting where T8 would traditionally be used.

Common lengths include 2-foot, 3-foot, and 4-foot, though T5 tubes use metric sizing based on their European origins – a "4-foot" T5 is actually 46 inches (1,149mm) rather than 48 inches like T8 tubes. This length difference means T5 tubes require specific T5 fixtures and are not interchangeable with T8 fixtures. The base type is miniature bi-pin (G5) with 5mm pin spacing, different from the G13 bases on T8 tubes.

Color temperature options mirror T8 offerings: warm white (3000K) for hospitality and retail environments wanting comfortable ambiance, neutral white (3500K-4100K) for offices and commercial spaces, and daylight (5000K-6500K) for industrial applications and areas requiring maximum brightness. T5 tubes typically offer excellent color rendering with CRI values of 80-85 standard, and 90+ CRI versions available for applications requiring superior color accuracy.

The performance advantages of T5 technology come with some practical considerations. T5 tubes achieve peak light output at higher ambient temperatures (95°F) compared to T8 tubes (77°F), which makes them particularly well-suited for enclosed fixtures where heat builds up but can reduce performance slightly in very cold environments. T5 tubes also require specific T5 electronic ballasts – they're not compatible with T8 or T12 ballasts. This means retrofitting T8 fixtures to T5 requires replacing the entire fixture or at minimum the ballast, sockets, and potentially the housing to accommodate the different tube length.

Lifespan for T5 tubes typically exceeds T8 performance, with rated lives of 20,000-30,000 hours and better lumen maintenance (less depreciation over time). A quality T5 tube might still deliver 90-95% of initial lumens at 10,000 hours, compared to 85-90% for typical T8 tubes. This sustained performance means better illumination levels throughout the tube's life and potentially longer intervals between replacements.

The decision between T5 and T8 typically depends on the application and whether you're working with new construction or existing fixtures. For new installations where efficiency, light quality, and slim profile fixtures are priorities, T5 offers clear advantages. For retrofits of existing T8 systems that are functioning adequately, the cost and complexity of converting to T5 usually doesn't justify the modest efficiency gains. LED linear replacements often make more sense than either fluorescent technology for major retrofits.

Standard Sizes: 2-foot (22"/569mm), 3-foot (34"/863mm), 4-foot (46"/1149mm). Note: metric sizing, not same as T8 lengths. Miniature bi-pin (G5) bases.

Performance Types: T5 HO (High Output - maximum lumens), T5 HE (High Efficiency - maximum efficacy)

Applications: High-bay lighting, indirect/architectural lighting, retail and hospitality, offices and commercial spaces, clean rooms, anywhere high-performance lighting is needed