If you live in California, then you are probably familiar with the dangers of wildfires. Wildfires spread quickly and cause a lot of damage to the ecosystem and neighboring towns. Setting aside the obvious danger from the spread of fire, the smoke can be equally as detrimental to your health. Massive plumes of smoke created by wildfire can damage your lungs, but were you aware that the smoke can cause damage to your eyes as well?

Exposure to smoke on any level can cause irritation to your eyes—symptoms such as burning sensations, redness, and tearing up are commonplace with exposure to smoke. Robert N. Weinreb MD, a distinguished Professor of Ophthalmology at the University of California San Diego, claims that “even a healthy person’s eyes can be bothered” when it comes to smoke exposure and, particularly in the case of those with dry eye syndrome, “exacerbate symptoms.”

What causes this irritation is the existence of small particles, which are two and one half microns or less in size (for reference: 25,400 microns = 1 inch), within the smoke that get stuck in your eyes. These particles are too small to be seen with the naked eye. These particles can remain floating in the air long after the smoke has cleared, so if you are around fire or a place where large amounts of fire have been recently, many firefighters recommend the use of protective eyewear.

Most of time eye irritation from smoke can be cured with the use of over-the-counter artificial tears and the use of a cold compress, but if your eyes remain irritated for longer than a few days you should consult your eye doctor.