Skip to Content

Does Fire Emit Blue Light?

Tablets, smartphones, and other electronics are frequently targeted as the sole emitters of blue light, but what about the world around us? As summer draws to a close and we move into the colder months of the year, many people will look to fire pits to create that cozy atmosphere associated with late autumn and the holidays. However, most have no idea whether they’re inadvertently exposing themselves to even more blue light than their daily routine requires. 

Fire does not emit enough blue light, and barely emits any at all. If you’re concerned about how much blue light you’re exposing yourself to, personal electronic devices and even daylight are worse offenders.

This article will dig a little deeper into why you sometimes see blue light when a fire burns, the varying effects of blue light, and if it’s bad for you. Some of the practical blue light applications if that tiny backyard bonfire were to become a raging inferno. 

Does fire emit blue light

Why You’re Seeing Blue Light

Where Is the Orange Coming From?

It’s pretty common knowledge that a flame’s color depends on its temperature. The cooler flames are typically yellow or orange, while hotter flames are blue. That’s why, when lighting a candle, the base of the flame is usually blue.

The flame’s base is the closest to the wick, or the fire’s source, where the fire will be the hottest. Other parts of the flame will be orange because they’re further from the fire’s source. 

However, the upper portion of a flame doesn’t follow the same rules, depending entirely on the type of material being burned. In things like a fire pit, for example, the vivid orange color you see throughout is usually due to sodium. 

Where Is the Blue Coming From? 

This is where the answer gets a little more complex. As previously explained, the blue flame in a wood fire is typically the result of high temperatures. Like the influence of sodium on a wood fire’s appearance, several compounds can also make fire appear blue. Carbon and hydrogen produce a blue flame when gas is fully oxidized in a gas fire, and copper compounds are responsible for the bright blue color present in fireworks. 

Does Fire Emit Blue Light?

Two factors determine a fire’s color, namely, proximity to a fire source or fuel, and the compounds present in the burning. 

Is Blue Light Bad for You?

Why Is It Around? 

Like most things found in nature, blue light does have a function in our everyday lives. If you’ve ever wondered why it’s easier for us as a species to be awake during the daytime, blue light is partially to blame.

It acts as a regulator to our circadian rhythm by suppressing melatonin production, keeping us awake and alert throughout the day. Lack of blue light exposure has also been linked to the development of near-sightedness in children. 

Everything Is Harmful in Excess 

Despite our need for blue light exposure, the mainstream and persistent use of personal electronic devices can lead to digital eye strain, causing fatigue, dryness of the eyes, and headaches. At its absolute worst, it can also cause long-term damage to your retinas. 

There are several ways to prevent this from happening, including limiting screen time if at all possible, using blue light filters installed on your devices, and using specialized glasses also meant to help filter blue light. 

The Relationship Doesn’t End There 

It was recently discovered by the National Institute of Standards and Technology (NIST) that blue light could be used in the event of a large or out-of-control fire to get visual data that couldn’t otherwise be obtained. In this case, the information being obtained would be how materials react and are influenced by fire over time, specifically in building construction and deterioration.

While this is limited to gas fires and fires that don’t generate a ton of smoke, no doubt using this imaging method will help contractors ensure citizens’ safety when designing and determining the materials for new building projects. 


While fire does emit small amounts of blue light, our exposure to it is negligible in the scope of our day-to-day lives. The meager amount of blue light generated in nature is much more palatable and serves to regulate our sleep cycle.

In contrast, the blue light from personal devices suppresses our brain’s melatonin production no matter what time of day it is or where you’re located. Excessive blue light exposure can cause strain on the eyes as well as headaches, so regulating your screen time and taking man-made precautions against prolonged exposure is the surest way to avoid unintentionally harming yourself. 


  • Vincent Steele

    Vincent is a freelance writer based in Santa Ana, California. When he isn't writing articles for Temperature Master, he can be found biking or hanging out with his cat, Shelly.

As an Amazon Associate, we earn from qualifying purchases. We may also earn commissions if you purchase products from other retailers after clicking on a link from our site.