Air conditioning can be a cool thing to have when it gets hot outside—literally and figuratively. But there can be drawbacks to staying in an air conditioned area too long, especially if what it’s doing to the air isn’t apparent.

You’ve probably experienced the relief of going from being bathed in heat and humidity to entering an air conditioned room. It can feel like that great reveal in a rom-com when two people realize that they are meant for each other. Thinking, sleeping, moving around and do seemingly everything can be a lot easier when you aren’t sweating profusely and feeling like a potato in microwave. Being in lower temperature surroundings can reduce the risk of heat-related problems such as dehydration and stroke. Plus, air conditioning can improve indoor air quality by filtering our different allergens, pollutants, insects and other organisms. Moreover, lower humidity can decrease the risk of mold growing and your stuff getting damaged.

However, it’s not always all rainbows and unicorns with air conditioning. One of the risks of air conditioning is that it can make the air too dry. Thais can dry out your eyes, skin and potentially airways. Therefore, it is a good idea to make sure that you stay properly moisturized and hydrated while staying in air conditioned areas for extended periods of times.

Another risk is not enough ventilation when the air is just re-circulated without replenishment with new fresh air. This can lead to the build-up of indoor pollutants from the various appliances and equipment that you are using. For example, running a laser printer can spew toner particles into the air that you may end up breathing in if there isn’t enough ventilation in the room. Similarly, if someone has brought infectious pathogens like severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) into the area, an air conditioned room may not have enough ventilation to keep it from hanging on to borrow words sung by The Supremes and Kim Wilde.

Therefore, stay aware of how much ventilation is occurring in a room. Check whether the air conditioner is simply re-circulating the same air or providing ventilation as well. See if the air conditioning unit is filtering the air too. If not, consider installing or using a machine that has a high efficiency particulate air (HEPA) filter than can effectively remove at least 99.97% of dust, pollen, mold, bacteria, and any airborne particles that are as small as 0.3 microns (µm). It also may help to periodically open the windows to air out the room.

A third potential risk is the air conditioning unit itself. All air conditioners are not created equally. They can vary significantly in design, quality and age. When an air conditioner is not kept clean, mold and other debris can build up in the machine, turning it into one of those mist machines you may see at a music concert, except that you can’t see the mist and all the bad stuff in it. A poorly designed or too old air conditioner can spew all sorts of other pollutants into the air. So, stay aware of what machines may be doing stuff to your air, regularly clean them and replace them if needed.

Finally, when you stay in air conditioned rooms all day, you may be missing all the great outdoors has to offer. Unless you live inside the Caesars Superdome—or whatever sponsor’s name is attached to it these days—in New Orleans, indoor areas may not provide you with enough room to stay as physically active. Remaining indoors won’t give you the benefits of exposure to sunlight—yes, the sun is not all bad—such as stimulating Vitamin D production and regulating your sleep-wake cycle. Then there are all the mental health benefits of being outside and exposed to nature.

So, before it gets too hot to handle, get a handle on how your indoor areas are being air conditioned. And even when the heat is on outside, try to still find ways to make it outside here and there as long as you take precautions.