Bulbs stop working for a multitude of reasons; this is nothing out of the ordinary.
If you’re anything like me, you probably keep a backup supply of spare bulbs in the cupboard. If not, replacement bulbs are readily available both online and offline.
Switching out an old bulb is a relatively straightforward task. However, with certain bulbs, you have to take extra precautions to avoid touching the bulb with your bare skin.
Does this apply to LEDs?
Since LEDs produce light through electroluminescence rather than heat, it is fine to touch them with bare hands. That being said, it’s best not to handle them any more than absolutely need to.
If you’ve never used an incandescent bulb before or are unaware of their workings, you may be intrigued about why they shouldn’t be touched.
Fear not, that’s what I’m going to be investigating in this article.
I’ll also be exploring why this doesn’t apply to LEDs, and setting out a full list of bulbs that shouldn’t be touched.
Why You Shouldn’t Touch Incandescent Bulbs With Hands?
To appreciate why incandescent bulbs should not be touched, you first need to understand how they work.
Incandescent bulbs consist of a thin carbon filament inside a glass vacuum bulb.
An electric current heats the filament until it becomes hyperactive and releases extra energy in the form of photons (light). Naturally, there is a lot of heat involved in this process.
Even if your hands are freshly washed, the skin contains natural salts and oils. Touching a bulb, or any object for that matter transfers these oils and contaminates the surface.
This is the premise behind collecting fingerprints for use as criminal evidence.
But oil is an excellent heat conductor. So these oily fingerprints create a hotspot on the bulb’s surface.
Essentially, when the bulb is turned on, the excess heat radiating off the carbon filament begins to heat the oily fingerprints.
As I’ve mentioned, incandescent bulbs require a lot of heat, so this oil can reach temperatures of 1,100 degrees Fahrenheit!
However, this creates a temperature imbalance, as the bulb is not evenly heated. The oily area of the bulb is now a lot hotter than untouched areas of the bulb.
The glass of an incandescent bulb is extremely thin, the hot spot will manifest into a weak spot.
Eventually, this weak spot will blister or crack, allowing air to penetrate the bulb and oxidize the carbon filament. If this happens, there’s likely to be a loud ‘pop’ sound, a flash of light, and the incandescent bulb will stop working.
Alternatively, in the worst-case scenario, an oily hotspot will cause the bulb to spontaneously shatter, sending shards of hot glass flying in all directions. I’m sure you agree that this is extremely dangerous.
For this reason, it’s essential to wear vinyl, latex, or rubber gloves when changing or fitting an incandescent bulb. If gloves are not available, you can hold the bulb using a clean paper towel.
Nevertheless, if you accidentally touch an incandescent bulb, remember to clean it with methylated spirit to remove any oily residue.
Does The Same Apply For LEDs?
Who’d have thought that something as trivial as fingerprints would be enough to make an incandescent bulb explode? I think this says a lot about their outdated, tenuous technology.
So what about contemporary light sources – is it okay to touch LEDs with bare hands?
LEDs produce light using a semiconductor chip – positively charged electrons meet with negatively charged electron holes to form photons (light). This process is known as electroluminescence.
Since this system involves no thermal radiation, it doesn’t matter if you get oily fingerprints on an LED bulb.
Don’t get me wrong, LEDs do produce heat, but nowhere near enough to heat the oil and cause a weak spot.
Even if a weak spot miraculously occurred and caused the bulb to crack or break, this would have no impact on the LED’s functioning.
Unlike incandescent and halogen bulbs, LEDs do not require a vacuum or inert gas to operate.
Despite this, it’s probably best not to manhandle your LEDs too much. While LEDs can tolerate oil and human touch, they’re not a toy and should be left alone as much as possible.
Related: Do LED Bulbs Use Tungsten Filaments?
What Types Of Bulbs You Shouldn’t Touch With Hands?
To summarise what I’ve covered so far: incandescent bulbs will break if they’re touched with bare hands, but LEDs will remain unaffected.
As I’m sure you’re aware, these are just two out of many types of bulbs. So what about the others, can they be touched?
Let’s start with halogen bulbs because of how they operate. These are often thought of as incandescents younger sibling.
Much like incandescent bulbs, halogens produce light by heating a metal filament.
The addition of halogen gas allows the tungsten particles to be redeposited onto the filament when the bulb is switched back off.
This is intended to increase the lifespan of the filament, and therefore the bulb.
Since they’re more robust than incandescent bulbs, halogens can be made brighter by running them hotter.
To accommodate this, the bulbs are made from quartz instead of regular glass.
It’s here that their problems lie.
As well as oils, touching a bulb also transfers sweat. Sweat contains salt (sodium), which, at high temperatures, can fuse with the quartz envelope.
But this new glass-like substance has a much lower melting point than the quartz alone. Consequently, when the bulb is switched on, this area will rapidly blacken and melt. This process is called vitrification.
Once a hole is made, and the halogen gas can escape, the bulbs’ filament will snap and cease working.
These problems with oil and salt apply to all bulbs that rely on thermal radiation and/or feature quartz bulbs.
Therefore, as a general rule of thumb, it is safe to touch all bulbs that do not have these attributes.
For a full breakdown, please see the table below.
|Type of Bulb||Can You Touch It With Your Hands?|
|Fluorescent / CFL||✓|
Thanks to advancements in technology, changing a light bulb is much easier than it used to be.
It’s no big deal if you don’t have gloves or a paper towel to hand, LED bulbs are safe to touch.
Nevertheless, if you want to air on the side of caution, you could always wipe over your bulbs with rubbing alcohol.
Did you know about the dangers of touching incandescent and halogen bulbs?
Do you feel comfortable touching LEDs with your bare hands? Let me know by writing a comment in the section below.
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