When purchasing a new bulb for my 200 chevy malibu I was given instructions not to touch the glass part of the bulb. I thought it was an odd instruction then later in the days while talking to my father he mentioned the same thing. Why is this? is it toxic or something?
I think the theory is that you’ll leave oils on the bulb which will cause the glass to heat unevenly and possibly break.
The halogen or similar units get very hot, and the dirt/oil from fingers should cause premature failure.
No, it’s not toxic, but it can shorten the life of the bulb, sometimes considerably. Your fingers deposit oils and other stuff on the surface in the form of a fingerprint. When this stuff heats up, it can weaken the glass to the point that invisible fractures form, allowing air in and the bulb fails. Sometimes, they can even shatter although this is more likely to occur in higher-wattage bulbs such as used in TV studio lighting.
Seller of Task lighting here. I have seen first-hand new bulbs shatter from having been touched. It’s the oils from your skin as noted above.
If you do touch it, all is not lost. Use a soft towel or rag soaked in a solvent like plain rubbing alcohol or acetone to wipe down the bulb before you’ve turned it on and wipe it dry. I imagine window cleaner would do well, too, since it does a fine job with fingerprints on windows. Best thing is to handle it while wearing clean, oil-free cotton gloves to begin with.
We did this one to death, gosh, seems like a year ago:
Pay particular attention to the excellent summation by yours truly:
http://boards.straightdope.com/sdmb/showpost.php?p=6969542&postcount=42
Missing from all the above explanations is that salts from your skin also have a deleterious effect on quartz glass. Quartz (i.e. pure SiO[sub]2[/sub]) glass is used because it has very low thermal expansion and so can withstand greater thermal shock than regular soda glass, which contains sodium to make it easier to work in the molten state. Sodium ions from your fingers will affect the expansion properties locally, leading to rapid failure.
Disregard all pseudo-scientific nonsense. The bulb are phobic and don’t like to be touched. It gives them issues, causing them to crack up.
:smack:
Why didn’t I think of that!
So what you are saying is these bulbs are kind of lighting equivalent of Adrian Monk, and have issues.
Perfect. Got it.
Chefguy it is official, you gave me my first laugh of 2007. Thanks.