Curiosity question on lighting.

[zbarry]

I was reading some posts on here and another site that talked about how curled and compacted uvb bulbs can cause blindness or other problems to tortoises eyesight. I myself don't use this kind of bulb I use powersun mercury vapor uvb bulbs, but I was just curious as to how people found out the curled and compacted bulbs were causing problems? And I was wondering if that means the one in the picture I have attached is bad cause I know some people that use that kind and I would like to give them a heads up? Thanks in advance.

 

[wellington]

Yes the one in the picture is'one of the bad ones
The bulbs were recalled a few years ago and supposedly fixed.
However, we still see many people using them and complaining of tortoise having swollen eyes or other eye issues.
The bulbs were not meant to be hung up and down but sideways.
I dont think the manufacturers say this any place on the packaging.
We recommend to just stay away from them. They not only can do damage but they aren't very good in emitting uvb.

 

[TeamZissou]

From what I've read, coil bulbs can produce UV light at shorter wavelengths toward the high end of the UVB range and even into the UVC range. UVC is very damaging. Hospitals and universities have been using UVC lighting to sanitize masks during the pandemic. Imagine that kind of light hitting a tortoise or anyone's eyes. That would be very damaging and painful.

I don't know if that particular bulb produces the harmful wavelengths, but the recommendation in general has been to avoid coil type bulbs altogether. The symptoms of damaged eyes are inflammation/swelling, eyes shut all the time. I guess if the damage isn't too bad, it can clear up in a few days.

MVB bulbs aren't great either, as they significantly dry out the carapace.

 

[wellington]

From what I've read, coil bulbs can produce UV light at shorter wavelengths toward the high end of the UVB range and even into the UVC range. UVC is very damaging. Hospitals and universities have been using UVC lighting to sanitize masks during the pandemic. Imagine that kind of light hitting a tortoise or anyone's eyes. That would be very damaging and painful.

I don't know if that particular bulb produces the harmful wavelengths, but the recommendation in general has been to avoid coil type bulbs altogether. The symptoms of damaged eyes are inflammation/swelling, eyes shut all the time. I guess if the damage isn't too bad, it can clear up in a few days.

Yes, most everyone if not everyone that we have told to stop using the bulb has had the eye issues clear up.
If any permanent damage had been done it has gone noticed.

 

[ZenHerper]

I was reading some posts on here and another site that talked about how curled and compacted uvb bulbs can cause blindness or other problems to tortoises eyesight. I myself don't use this kind of bulb I use powersun mercury vapor uvb bulbs, but I was just curious as to how people found out the curled and compacted bulbs were causing problems? And I was wondering if that means the one in the picture I have attached is bad cause I know some people that use that kind and I would like to give them a heads up? Thanks in advance.

Here is a resource about compact bulbs to pass on:

UV Lighting for Reptiles: A new problem with high UVB output fluorescent compact lamps and tubes?

MVBs are also very irregular in their output, and many produce short wavelengths as well. If you want to continue using them, definitely get a uv meter so that you know what any one bulb is producing EVERY DAY that you turn it on (optimally check several times a day), don't run them all day long, and adjust the height depending on what the meter reads.

The long tubes are just superior and safer in every way.

 

[ZEROPILOT]

I'm with @ZenHerper
I do not reccomend MVB bulbs.
They do not provide reliable, consistent UVB.
In fact, they do nothing very well.
I have a post somewhere in which I tested several of them.
The results were unsettling

 

[ZEROPILOT]

These work well and cause no harm
As far as I'm concerned, CFL and MVB have no use in this hobby
I've got a few hundred dollars of MVB in a box in my garage that I just cant seem to throw away. Simply because I wasted so much money on them

 

[zbarry]

That's interesting. I will definitely look into changing from MVB.