“Tube light” – It is very familiar to everyone and can be noticed almost everywhere in houses, offices, hospitals, etc. But, do you know that not all tube lights are same? Do you know that there are three different types of tube lights? Yes, there are three different types of tube lights and they are T12, T8 and T5 tube lights. Let us see in this article, how they differ from each other and which is better by comparing some key parameters like cost, energy consumption, durability, performance, pleasantness of the light and the affect on environment.
Dimensions
Before we look into differences in their dimensions, let us first understand what does the codes T12, T8 and T5 mean. “T” means tubular (structure of the bulb) and the numbers 12, 8, 5 means the diameter of the the tube light measured in 1/8th inch.
| Tubelight (type) | Diameter (inches) | Length (inches) |
| T12 (regular) | 1.5 | 48 inches |
| T8 (thin) | 1 | 48 inches |
| T5 (Ultra thin) | 0.62 | 45.2 |
T5 tube lights are thinner and shorter.
Cost
The prices for 4 ft tube lights that emit 2,500 lumens of brightness are
| Tubelight (type) | Initial cost | Maintenance |
| T12 (regular) | Rs.40.00 | Stand-Rs.300(forever), Ballast-Rs.150(50,000 hrs), starter-Rs.20(5000 hrs) |
| T8 (thin) | Rs.48.00 | |
| T5 (Ultra thin) | Rs.140.00 | Special ballast – Rs.500(10,000 hours) |
Initial investment and maintenance is cheaper in T12 and T8 while T5 tube lights are significantly expensive.
Energy consumption
Energy consumed to emit 2,500 lumens brightness
| Tubelight (type) | Energy Consumed |
| T12 (regular) | 40 Watt |
| T8 (thin) | 36 Watt |
| T5 (Ultra thin) | 28 Watt |
T5 tube lights comparitively consume less energy than T12 and T8s
Durability
| Tubelight (type) | Durability(in hours) |
| T12 (regular) | 10,000 |
| T8 (thin) | 10,000 |
| T5 (Ultra thin) | 15,000 |
T5 tube lights have 50% more life span than T8 and T12 tube lights
Performance
| Tubelight (type) | Lumens per watt | Utilization |
| T12 (regular) | 78 | 0.46 |
| T8 (thin) | 92 | 0.76 |
| T5 (Ultra thin) | 103 | 0.9 |
Note: Utilization is often measured in CU (co-efficiency of utilization) which is the ratio of light fallen on the plane or surface to the total light emitted from the light bulb.
Performance of T5 tube lights is little more than T8 and T12 tube lights
Pleasantness of the light
| Tubelight (type) | Color of light |
| T12 (regular) | 62 CRI |
| T8 (thin) | 85 CRI |
| T5 (Ultra thin) | 85 CRI |
Note: CRI is color rendering index used to represent color and nature of the light emitted.
The more CRI, the whiter the light is. So, T8 and T5 tube lights emit bright day light that is pleasant. But, since T5s are thinner and smaller they glare and are harsh on eyes.
Environmental friendliness
| Tubelight (type) | Mercury content |
| T12 (regular) | 21 mg |
| T8 (thin) | 10 mg |
| T5 (Ultra thin) | 6 mg |
The less mercury content, the more eco friendly it is. Hence, T5 tube lights are eco-friendly
Conclusion
Among the three, T12s are inefficient. So, there is no point in comparing it with T8s and T5s. And, with little extra performance, T5 tube lights are way too expensive than T8 tube lights. So, T8s are economical than T5s.
Note: It is better to dispose tube lights after 6,000 burning hours because it contains mercury; with light rays, it may cause skin rashes. So, it is better to dispose them and dispose them carefully witout breaking and getting into direct contact with the mercury in the tube light.