Fact Check

Do CFL Light Bulbs Emit Harmful Levels of Radiation?

CFL light bulbs are claimed to be dangerous compared to conventional incandescent bulbs because they emit higher levels of radiation.

Published Mar 29, 2015

 (Kyrylo Glivin / Shutterstock)
Image Via Kyrylo Glivin / Shutterstock
CFL light bulbs are dangerous compared to conventional incandescent bulbs because they emit higher levels of radiation.
What's True

The use of some types of CFL bulbs results in greater exposure to some forms of radiation than incandescent bulbs under some conditions.

What's False

It's not true that all use of CFL bulbs should be avoided because they emit harmful levels of radiation.

On 23 March 2015, a video that purportedly showed a radiation detector picking up a "soft attack" from a CFL (compact fluorescent lamp) was posted to Facebook from an unvetted and anonymous source, along with claims that CFLs are dangerous because they emit unhealthy levels of radiation:

If you are using these type of bulbs, I'll show you the reason why you should not. Here I have a electromagnetic radiation detector. We're at zero right now. When I come to this light bulb, you'll see why you shouldn't use it.(Radiation detector starts beeping)

That's how much radiation these things emit. I advise you to go back to the old incandescent. This is not healthy for you.

Claims about electromagnetic radiation and electromagnetic fields (EMFs) — produced by everything from radios to light bulbs to cell phones — causing deleterious health effects have been around for decades, with no definitive scientific evidence proving such claims. The World Health Organization (WHO) concluded in a survey of available scientific literature on the topic that "current evidence does not confirm the existence of any health consequences from exposure to low level electromagnetic fields" such as those produced by CFL bulbs:

In the area of biological effects and medical applications of non-ionizing radiation approximately 25,000 articles have been published over the past 30 years. Despite the feeling of some people that more research needs to be done, scientific knowledge in this area is now more extensive than for most chemicals. Based on a recent in-depth review of the scientific literature, the WHO concluded that current evidence does not confirm the existence of any health consequences from exposure to low level electromagnetic fields.Some members of the public have attributed a diffuse collection of symptoms to low levels of exposure to electromagnetic fields at home. Reported symptoms include headaches, anxiety, suicide and depression, nausea, fatigue and loss of libido. To date, scientific evidence does not support a link between these symptoms and exposure to electromagnetic fields. At least some of these health problems may be caused by noise or other factors in the environment, or by anxiety related to the presence of new technologies.

Moreover, a Science-Based Medicine round-up of claims surrounding CFLs noted that although those lamps can put out more EMF than other types of bulbs, that fact poses no health hazard. Moreover, the EMF levels fall off so sharply with distance that measuring them from a few inches away (as shown in the video) is highly misleading:

The major health claim being made against CFLs, however, is that they put out "dirty electricity" which can allegedly cause a variety of health problems. There is now a video circulating on Facebook making such claims. Fear of dirty electricity goes beyond CFLs — the new bulbs are just the latest target.What about CFLs specifically? They do indeed put out more EMF in certain frequencies than incandescent or halogen bulbs, but there is no evidence that this level of EMF poses any health consequences. Further, one thing is absolutely clear — EMF falls off sharply with distance. Even after a couple of feet the EMF put out by light bulbs falls from tiny by many orders of magnitude to negligible. The EMF intensity at a distance of inches (as shown in the Facebook video) is irrelevant.

What about other forms of radiation emitted by CFLs, such as ultraviolet (UV)? A Canadian government study in 2009 found that CFL light bulbs do result in exposure to more UV radiation when used within a distance of one foot from the subject. The United Kingdom Health Protection Agency came to a similar conclusion, and the FDA recommends that single-enveloped CFL light bulbs should not be used at distances closer than one foot for more than one hour per day:

Unless you are one of the few individuals who have a medical condition (such as some forms of Lupus) that makes you particularly sensitive to either UV or even visible light, you should be able to use these lamps at the same distance as you would use traditional incandescent lamps. However, a recent study from the United Kingdom Health Protection Agency has found that there are measureable levels of UV from single envelope CFLs when used at distances closer than 1 foot. As a precaution, it is recommended that these types of CFLs not be used at distances closer than 1 foot, for more than one hour per day.

This does not, however, mean that CFL light bulbs are unsafe for consumer use. In fact, the aforementioned organizations all concluded that CFL light bulbs are just as safe as incandescent light bulbs when used at a distance greater than one foot:

CFLs as demonstrated by the test results do not pose a health hazard to the general population from either the ultraviolet radiation or the associated electric and magnetic fields. UVR At 30 cm, single-envelope CFLs have a maximum daily UVR exposure similar to the test results for a 60W incandescent lamp. Therefore, it is recommended that single envelope CFLs not be used at distances less than 30 cm to avoid any long-term health effects in the general population.Based on an analysis of the spectral irradiance data for CFLs at a distance of 30 cm, (and by extension greater distances), the bulbs do not pose a significant risk of acute injury to the eyes or skin, as compared to traditional incandescent lamps.

It should also be noted that the amount of UV radiation emitted from a CFL bulb can be reduced by using double-enveloped (enclosed in a second layer of glass) bulbs. In fact, double-enveloped CFL light bulbs were found to emit less radiation (even at distances as close as 3cm) than incandescent light bulbs:

The glass used in CFLs already provides a UV filtering effect. In addition, any additional glass, or plastic, or fabric used in lighting fixtures that is between you and the CFL will further reduce the already low levels to still lower levels since these materials act as additional UV filters. Increasing the distance between you and any radiation source, including CFLs, will also reduce the small level to a lower level.However, if you still wish to take additional steps then you might wish to purchase the type of CFL that has an additional glass or plastic cover that enclosed the CFL to make it appear more like a traditional incandescent lamp. These covers provide an additional reduction of the low level of UV to a lower level.

While it is true that CFLs may emit more radiation that other types of light bulbs at short distances, CFLs are considered just as safe as incandescent light bulbs for general use.


FDA.   "Compact Fluorescent Lamps (CFLs) — Fact Sheet/FAQ."     4 June 2014.

Kiger, Patrick.   "Separating Myth from Fact on CFL and LED Light Bulbs: Five Concerns Addressed."     National Geographic.   8 January 2014.

Dan Evon is a former writer for Snopes.

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