I noticed some flickering in a light fixture that uses compact flourescent bulbs. Examining the bulbs, I saw that one of them was not firmly attached to its base. I can actually move the glass part of the bulb back and forth. For whatever reason, after I wiggled the glass part of the bulb a bit, the flicker was gone when I turned the lamp back on. But I am concerned about safety issues. So long as the bulb is not broken should it be safe to continue using it in this lamp, or could mercury vapor be escaping into the environment through the interstice between the bulb and its base, since the glass part of the bulb is not firmly attached? Thanks in advance for your input.

 

Welcome to the forums! No gas has escaped if the bulb is working. However, if the glass part is loose from the base, I would replace the bulb.

 

Hi Chandler. Thanks for your reply. Just out of curiosity, where is the actual mercury contained in these bulbs? Is it evenly distributed along the rods or in one specific location? The bulb is still working, but I am surrpised it is. I can clearly see a gap where one of the rods is completely removed from the base, but it is emitting just as much light as the others. It seems like the fact it is kind of hanging there unattaced would create an opening for the gas to escape? I would like to learn more so I know in the future, in case I have any other problem with this type of bulb. Reading on the net about bulbs that have actually broken I came up with contradictory information, with some people considering the break a very serious matter and others saying the amount of mercury released from one broken bulb was insignificant and would not have any health repercussions.

 

A fluorescent tube is filled with mercury vapor and inert gas. Straight, bent and curled fluorescents are all made the same way. No mercury is released until and unless the tube is broken.

The base of a CFL serves many purposes, including connecting to power and housing the ballast, or transformer. It also holds the tube or tubes in place. Occasionally, that holding bond is broken and the tube can move while the base remains still. So long as the tube and the electrical wire to it are still both intact, the tube can emit light as it was designed to do.

That said, I would replace it right away, as Larry suggested. The only thing holding it together now is the thin electrical conductor. That could fail at any time and, if the tube fell onto a hard surface, it might shatter, leaving you with released mercury and bits of sharp glass with mercury on them.

While the amount of mercury in a CFL is tiny, it is still a toxic substance and should be treated with caution. Replacing this bulb with a solidly connected one, and properly disposing of this one, will help do that. Personally, I would replace it with one with a cover, both to contain a loose tube and, more importantly, to reduce the amount of UV radiation in the house - particularly if the bulb is visible and it is lighting an area where you, or others, are likely to sit for extended periods.