| Product Type: | Replacement Lamp |
|---|---|
| Size: | 1-1/2" |
| Used With: | UV-12 |

The bulbs are mercury vapor bulbs so it is common to see little mercury beads in the bulb.
The silvery ball is mercury. The bulb ionizes mercury vapor to create the UV light. It should be treated as hazardous waste when the bulb is replaced. A facility that recycles fluorescent lights should be able to accept the used bulb. Not sure about it being defective. Most manufacturers try to minimize the amount of hazardous material in their products.
I don't think this is a problem. In fact, I think it is necessary for the ball to be present for the light to work properly, part of the chemical reaction that produces the light in the cylinder. You could try contacting the manufacturer for more details Thank you, Forrest Livings Skyview Elementary Sent from mobile device, please excuse any typographical errors.
My understanding is that it is a 12 month bulb when my HVAC technician checked the bulb at 12 months that the bulb did not need to be replaced for another ~6 months or longer.
It is one year bulb.
I believe it is a one year bulb, however, I've been getting about 18 months out of them. Thank you, Forrest Livings
The bulb should be replaced each year upon recommendation from tech & manufacturer of my heating unit.