Guide to UVB Lighting: What Bulb Do You Choose?

UVB lighting is something that is so important to reptiles and is one of the key aspects to truly successful husbandry. I have made videos on why snakes need UVB lighting and why every reptile should have access to it. That’s great, we have established how important UVB lighting really is, but we haven’t actually tackled the topic of how you should provide it, or how to choose what bulb to use.
I’m going to aim to make this the most detailed guide on UVB lighting on Youtube , so bear with me, we are going to go into some serious detail here, By the end of this video I hope to have explained the topic well enough for you to make an educated decision for your animals, to make this video a easier to use tool in the future I will break this video into chapters, you should see the segmented timeline bar at the bottom of the video as well as timestamps in the description.
First of all, lets go over some of the things you are commonly told about UVB lighting in pet shops. One of the things you are told is that a 12% desert tube is for a bearded dragon and a 7% Tropical tube is for a chameleon. But what does that actually mean?
Bulb percentages
The percentage listed on a bulb, is the percentage of the bulbs output that is UVB. So for example, a 7% UVB Arcadia shade dweller is also 17% UVA and 76% visible light. So the higher the percentage of UVB listed, the higher the intensity of the UVB available. This is why people refer to these 12% UVB bulbs as being used for sun baskers like bearded dragons.
So that’s it were done right? Well no, its not as simple as that. This isn’t taking into account the distance between the bulb and where the animal will be able to bask from.

The strength of the suns ultraviolet radiation is expressed as the ultraviolet index or UVI for short. The stronger the radiance, the higher up the indices we get. For example, a really clear sunny day in the UK we might get a UVI of 4 and on a cloudy not so sunny day we may have a UVI of 1 or 2.
So, each species has a preferred UVI they bask at that both meets their needs and is at safe levels.
This can be measured with a solarmeter, which is a handheld device with a sensor, when you press the button it gives you a reading. This is exactly what Gary Ferguson et al used in 2010, that UVI that wild reptiles in the wild were basking at was recorded as well as the habitat and light availability, species were then divided into four UVB zones which we now know as Ferguson zones.
These zones are:
• Zone 1 – crepuscular or shade, thermal conformer.
• Zone 2 – partial sun or occasional full sun basker, thermoregulator.
• Zone 3 – full sun or partial sun, thermoregulator.
• Zone 4 – Mid day sun basker, thermoregulator.
You will notice each of these zones represent difference ranges of UVI. It is the correct UVI at the basking spot that we desire, not what percentage is listed on the bulb and creating some arbitrary link to a certain species.
So how does percentage link to UVI? Well the higher the percentage, the higher the UVI is at an equal distance to the basking spot than a lower percentage bulb.
So lets say we had a reptile that needs a UVI of 4. A lower percentage bulb would need to be at a closer distance to achieve a UVI of 4, but a far higher percentage bulb would need to be much further away to achieve a UVI of 4, or we risk a much higher number than we want.

The Arcadia lighting guide:
https://www.arcadiareptile.com/lighti...

ZooMed lighting guide:
https://zoomed.com/wp-content/uploads...

Exo Terra lighting guide:
http://www.exo-terra.com/download/lig...

Reptile Systems:
https://www.aquariumsystems.eu/fergus...

Support the channel:   / reptilesandresearch  

Timestamps:
0:00 Introduction
0:45 Percentages on the bulbs?
1:29 Ultra Violet Index
2:03 Ferguson Zones
2:50 How does percentage link to UVI?
4:18 Shade & Sunbeam method
5:38 Different bulb types
6:13 Different brands
6:34 Arcadia Reptile
6:47 Exo Terra
8:02 ZooMed
8:35 Reptile Lighting FB group
9:00 Reptile Systems
9:23 Mesh affects output
10:04 Glass blocks UVB
10:11 Selecting bulb position
10:49 Solarmeter 6.5
11:54 Summary
12:44 Thank you Dr Baines

References:
Baines, F. M., Chattell, J., Dale, J., Garrick, D., Gill, I., Goetz, M., ... & Swatman, M. (2016). How much UVB does my reptile need? The UV-Tool, a guide to the selection of UV lighting for reptiles and amphibians in captivity. Journal of Zoo and Aquarium Research, 4(1), 42-63. https://ww.jzar.org/jzar/article/view...

Ferguson, G. W., Brinker, A. M., Gehrmann, W. H., Bucklin, S. E., Baines, F. M., & Mackin, S. J. (2010). Voluntary exposure of some western‐hemisphere snake and lizard species to ultraviolet‐B radiation in the field: how much ultraviolet‐B should a lizard or snake receive in captivity?. Zoo biology, 29(3), 317-334.https://onlinelibrary.wiley.com/doi/a...