Understanding Different Types of Fluorescent Lights: T5 vs. T8 vs. T12 | Shine Retrofits Lighting Blog (2024)

FAQs

Understanding Different Types of Fluorescent Lights: T5 vs. T8 vs. T12 | Shine Retrofits Lighting Blog? ›

T5 lights are the most energy-efficient and ideal for spaces where energy savings are a priority, while T8 lights strike a balance between efficiency and brightness, making them suitable for general lighting. T12 lights, while less efficient, may still be found in certain settings.

T8 bulbs use about 35% less electricity to produce the same amount of light as a T12. T5 bulbs use about 45% less energy than T12s. For some applications, one T5 bulb can replace two T12 bulbs, providing even greater energy savings (a process called “de-lamping.”)

T8 LED lamps which are not direct-wire compatible (with ballast) will require a T8 ballast to operate, so unless the T12 ballast in the T12 fixture is replaced with a T8 ballast, a non-direct-wire compatible T8 LED lamp will not work in a T12 fixture.

Full-size fluorescent lamps are available in several shapes, including straight, U-shaped, and circular configurations. Lamp diameters range from 1" to 2.5". The most common lamp type is the four-foot (F40), 1.5" diameter (also called T12) straight fluorescent lamp.

T8 bulbs come in standard 2-, 3-, 4- and 5-foot lengths. Comparable T5 bulbs are slightly shorter than T8 bulbs. Make sure you check your existing fixture carefully because the two types of bulbs are not interchangeable.

Why are my light bulbs phased out? In July 2012, the U.S. Department of Energy's lighting mandate took effect. Fluorescent T12 lamps and ballasts were phased out and are no longer legal to be produced or imported.

In 2023, T5 and T8 fluorescent and compact fluorescent lamps (CFLs) were phased out in accordance with the European Commission's Ecodesign and RoHS Directives. The reason is to remove the most energy- and resource-demanding products from the market and the use of environmentally hazardous mercury.

Can You Replace a T12 With a T8? When the new lighting standards went through Congress a majority of buildings began to use one of two replacements. The first was T8 fluorescents, but in some cases you can also replace the T12 with a T5 linear fluorescent.

As far as safety is concerned, you can exchange them. If you place T12 tubes in a fixture with a T8 ballast, you will wear out the ballast and have to replace it. If you place T8 tubes in a fixture with a T12 ballast, then the tubes will have a shorter life due to a higher current through the tube.

T8 = 1-inch diameter. T12 = 1-1/2-inch diameter.

Can you change a T12 ballast to a T8? ›

yes you can change from T12 to T8, Just change the light, and you are done.

You can tell the size and maximum wattage rating for a fluorescent tube by the code detailing its dimensions. T8 for example, means tubular (T) followed by the size/diameter (8). There may also be an abbreviated "HO" which indicates a high-output and "VHO" for very-high-output.

The average life expectancy of a fluorescent light ballast is 10-15 years. Any ballast beyond that age should be considered to be at a heightened risk of failure.

T5 light bulbs are available in high efficiency and high output options. High efficiency lamps operate at lower wattages and produce a standard light output. High output lamps deliver more light than high efficiency versions and use a higher wattage.

T5 lights are the most energy-efficient and ideal for spaces where energy savings are a priority, while T8 lights strike a balance between efficiency and brightness, making them suitable for general lighting.

Make sure you know what kind of lamps you're using because a T8 ballast will not work for T5 lamps. While we are focusing on fluorescent lamps in this article, it's also important to check that the tubes aren't self-ballasted LEDs.

The amendments to the RoHS directives from last spring put the end of the fluorescent tube a few days earlier: from August 25, 2023, T8 lamps will be phased out together with T5 fluorescent lamps. It will also hit compact fluorescent lamps with plug-in bases as early as February 25.

What are the new changes to the RoHS Directive regarding fluorescent tubes? From 1st September 2023, T5 and T8 fluorescent tubes will be phased out altogether. All business owners are required to source alternative lighting solutions and discard them as hazardous waste, or through structured recycling to be compliant.

In effect since July 2012, the legislation eliminates nearly all 4-foot T12 lamps, some 4-foot T8 lamps, most 8-foot T12 lamps, and almost all standard halogen PAR38, PAR30 and PAR20 lamps from the market. T12 technology is over 80 years old. Since that time, lamps and bulbs have been developed that just work better.

The main difference between 8ft T8 bulbs and 8ft T12 bulbs is the tube's diameter. T12 tubes are 1.5" in diameter while T8 tubes are just one inch. All other things—socket sizes, lengths, distance between pins—are the same.

How to tell if you have a T8 or T12 ballast? ›

T8 = 1-inch diameter. T12 = 1-1/2-inch diameter.

Energy Efficiency: T8 fluorescent lights are energy-efficient, offering improved efficiency compared to older T12 models.

Method One - Use your smart phone camera

Stand under the light or a place close to the light and point your cell phone camera at the light. If you can see some strong dark strips flickering in your camera, it must be a magnetic ballast based light. Otherwise it should be an electronic ballast based light.