Knowing what is a comfortable humidity level outside is crucial as it helps determine how to carry on with activities of the day.
A comfortable humidity is the amount of moisture in the air that’s not only appropriate but conducive to a healthy existence.
For many people, the humidity level considered comfortable is between 30 percent and 50 percent. Humidity levels are variable, with more humidity during the summer and less during the winter. Humidity levels also vary from place to place and seasonally.
What is Humidity?
Humidity is the amount of water vapor in the air. In most places, humidity levels in the air are reasonably stable throughout the year.
The two main types of measurable humidity are absolute humidity and relative humidity.
Absolute humidity is the mass of water vapor in a volume of air at a given temperature, divided by the abundance of dry air in that same volume.
When the temperature increases, the water content increases. Absolute humidity is expressed as the number of grams of water vapor in a cubic meter of air (g/m3).
The relative humidity is the ratio of the current amount of water vapor in the air to the amount of water vapor that would be present in the air if it were already saturated with water vapor.
When the relative humidity of the air rises to 100 percent, that means that the air can’t hold more water vapor than it already has.
Fact: If the relative humidity is at 100 percent where the clouds are forming, you're likely to experience some rainfall even if the relative humidity just above the ground is more diminutive.
Now that we’ve understood the comfortable humidity range, what humidity level is uncomfortable? There’s no set humidity threshold above which discomfort starts to increase.
However, the National Oceanic and Atmospheric Administration considers relative humidity levels of 50 percent or more and dewpoints (a direct measure of relative humidity) above 65 F to be high and uncomfortably.
70 Percent Relative Humidity
The Building Science Corporation found that high humidity levels adjacent to a building surface can cause severe damage to the property.
The Health and Safety Executive recommends that indoor relative humidity be maintained between 40-55 percent, while other experts recommend a 30-60 percent level.
High Humidity and Sweating
But when the temperature is high, a humid day makes it hard for sweat to evaporate into the air. This causes a hot, sticky feeling.
So, moisture remains on our skin, unable to evaporate into the air. As a result, our bodies continue to pump out sweat, but we don’t feel any relief.
DewPoint and Humidity
The dew point is the temperature the air needs to be cooled to, at constant pressure, in order to achieve a relative humidity of 100%.
If the humidity reaches 100% before the temperature has dropped this far, then water will condense out of the air as water droplets.
Though there is no hard and fast definition, most people agree that dew points in the 50s or lower are comfortable during the warm months.
When dew points reach 60 to 65, you feel sticky or humid.
If you live in a tropical climate, dew points of 70 or higher can make it hot, especially if there is little wind and the sun is shining brightly.
Outdoors Humidity and Breathing
Breathing is one of the major reasons why it’s important to know what is a comfortable humidity level outside.
Humid air is heavier than dry air.
It has a greater mass per unit volume, and this makes it harder for your body to move the molecules of humid air into your respiratory system so that your cells can absorb oxygen.
In low humidity, the mucous membranes lining the respiratory tract are inflamed and dried out. As a result, the risk of colds, flu, and other infections is increased.
Note: You're likely to feel lethargic and tired on a humid day.
Uncomfortable Humidity and Animals
“Panting” is the name of the process by which animals cool themselves by evaporating moisture from their lungs.
In order to pant efficiently, they need a certain amount of humidity in the air or they won’t be able to get rid of enough heat to keep their body temperature down.
Hot and humid weather can be difficult for animals like cattle to tolerate.
It’s even tougher when high humidity is accompanied by precipitation that reduces the ability of the animals to evaporate water from their respiratory tract or skin.
Evaporative cooling — the process of sweating or expelling moisture from the animal’s respiratory tract and skin — is the primary means by which cattle cool themselves, so they have a more difficult time in wet, humid weather.
Effects of Uncomfortably Low Outdoors Humidity
1. Eye Health
When a person stays outdoors in a low-humidity environment, their eyes tend to become dry and irritated.
According to research, low humidity can also dry eyes through increased evaporation of tears.
This imbalance in tear moisture levels affects the eye mucus, which is necessary for proper function.
Researchers found that at 72°F and humidity levels between 15-25%, a sudden drop in the quality of the eye mucus becomes visible.
2. Excessive Blinking
Dry air can make you uncomfortable, but it also interferes with your performance and productivity.
When the humidity is too low, your eyes water more frequently than average.
More watery eyes can lead to visual problems like blurred vision, making it harder to work on tasks like reading or doing paperwork.
Fact: The healthy tears on the surface of your eyes are essential for keeping them clear and preserving their nutrition, as well as for maintaining their antimicrobial defense mechanisms.
3. Scared Skin
In low humidity, the skin becomes flaky and itchy. In wintertime, your skin suffers from dryness, which can manifest in scaly and itchy patches.
These cracks can be not only uncomfortable but also dangerous, as they increase your risk of infection.
Winter itch is a form of eczema that tends to cause dry, itchy skin in the winter months.
A lack of moisture in the air, combined with the cold temperatures outside, can cause the moisture in your skin to evaporate and make your skin dry at the surface.
Cracks can also develop because of this process.
4. Spreading Viruses
In dry weather, viruses in the air have a greater chance of getting into your body and making you sick because they survive for longer periods and are more easily carried around by particles.
Since droplets usually spread viruses, sneezing does not get rid of them, especially in low humidity.
When someone sneezes, the droplets go flying through the air, but the viruses remain in their droplet form, floating everywhere for a long time.
After someone has sneezed, you can become infected if you have contact with one of these droplets.
Humidity and Sleep Quality
Too little or too much humidity can ruin your beauty sleep. Low humidity makes you feel sticky and uncomfortable; high humidity makes you feel clammy and uncomfortable.
It’s also important to note that mild changes in humidity levels will not affect the quality of your sleep.
But severe swings between high and low humidity that occur within a short period of time may cause sleep disruptions.
However, when you come in from the cold, your body will quickly cool down, just as it will when you emerge from a warm shower.
Note: The varying temperature extremes of such rapid heating and cooling result in sleep interruptions that prevent you from achieving REM sleep—the dreaming stage of sleep.
By maintaining the proper humidity levels, you will have a healthier sleeping and living environment.
Your respiratory health will improve, you will get sick less often, and you’ll feel more comfortable in your surroundings.
When air is dehydrated, you are more likely to have issues with your hair or skin drying out, and experience cracked furniture.
It’s important to know what is a comfortable humidity level outside because it helps beware of allergic reactions that may arise.
If too much moisture in the air, a home may become infested with pests and dust mites. Furthermore, excess humidity can encourage mildew and mould to grow.