Frequent questions

We solve the most frequent doubts about the portable air quality monitor

Huma-i skyblue (HI-120)

If you have any doubts

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When is self-calibration required?

Most gas sensors are affected by the external environment and are likely to change.

Sometimes you’re required to calibrate the sensor by yourself during ventilation or near the window.

Self-calibration cycle,

When VOC does not drop below 0.050ppm during ventilation and/or,

How can I do self-calibration by myself?
  1. Charge for more than 1 hour while the product is off.
  2. Place the product indoors or in a clean environment for more than 5 minutes.
  3. Press and hold the “Power button” until the Huma-i logo is displayed.
  4. "CALIBRATION" is displayed on the screen, and calibration is performed automatically for 3~4 minutes.*** If "CALIBRATION" is not displayed on the screen, turn off the product and return to step 3.
  5. When calibration is finished, the product automatically turns off and on.

PM2.5 and/or PM10 measurement shows “0”

If the value is "0" during measurement, a purifier is operating properly.

If "0" is continuously displayed, the small particles in the sensor area are occasionally stuck to the sensor side due to electrostatic phenomena, which prevents normal measurement. In this case, blow off the suction side of the device strongly 2 or 3 times and it will work normally. This is located on the left side of the product front. If this is not the case and you keep seeing "0", please contact the customer service center nearby.

It turns off automatically after 10 minutes

It is designed to automatically power off when there is no operation for 10 minutes to protect battery life.

If you want to use it continuously, then press the power button lightly to extend the use for another 10 minutes.

The automatic power-off function does not work when the power cable is connected.

There is a slight vibration after power-on

Huma-i shows the air quality level in real-time as the internal fan is actively and constantly sucking in the air just around you.

The fan makes a slight vibration tone.

If you rub a tissue lightly on the fan inlet, you can see that the value changes in real-time.

If you want to learn more about Huma-i measuring algorithm, click the link below.

Recommendation for VOC measurements

We recommend using the following:

1. When you receive the product for the first time, please charge it for more than one hour.

2. We recommend that you connect it to the charger before going to bed.

(It is better to charge the battery frequently as well)

The temperature seems to be measured too slowly

Since the sensor is mounted inside the product, the measurement time may be delayed.

Depending on the external temperature, the measurement time may be different.

The measurement deviation is 5% ~ 10%.

Characters blink in integrated display mode

The integrated display mode displays PM2.5/PM10/VOC or PM2.5/VOC at once in graph form. 

If the measured value is “POOR” or greater than or equal to that level, the letters of each item will blink and warn you.

If the alert function is working, and the air quality is at POOR or UNHEALTHY level, we strongly recommend you to ventilate or wear a mask.

What is shown in the integrated display mode?

Huma-i black model displays PM2.5/PM10/VOC and PM(PM2.5 and PM10 AUTO)/VOC/CO2 with two kinds of integrated display mode.

This mode is displayed in graph form on one screen with 4 categories – GOOD, MODERATE, POOR, UNHEALTHY.

Each category has 18 steps. (72 steps in total)

Even if you do not see the numerical value directly, you can see it in 72 steps, which is very intuitive.

VOC level is high when I wake up in the morning

If you do not ventilate by closing the door overnight, VOC may be released overnight in a new house or new furniture containing hazardous substances, which may increase the VOC level of the house.

Many products used daily can release harmful substances, and the higher the number of such substances, the higher the VOC level can be. Volatile Organic Compounds such as formaldehyde are gradually reduced by frequent daily ventilation.

We recommend that you ventilate in the morning, and ventilate more often if the VOC level is high.

VOC levels do not drop on a purifier

Most purifiers filter out more than 99% of fine dust, but VOC cannot be filtered like fine dust. In order to remove VOC, which is a volatile harmful substance such as formaldehyde, it is most effective to remove the cause or to constantly ventilate daily.

What is hazard of VOC?

The health effects or symptoms of VOC are;

- Irritation to eyes, nose and throat.

- Causes headaches, loss of coordination and nausea.

- Causes allergic skin reactions.

- Causes shortness of breath, nausea and vomiting.

- Causes fatigue and dizziness.

- Causes liver, kidney and central nervous system damage.

- Some organisms can cause cancer in humans and animals.

Especially methylene chloride (contained in adhesive removers and aerosol spray paint) is known to cause cancer in animals.

Benzene is a substance that causes cancer in humans.

Indoor sources include cigarette smoke, stored fuel, paint supplies, and automobile exhaust.

What is the baseline of VOC level?

Huma-i air quality monitor follows the recommendations of the German Health Ministry, which is divided in 4 levels:

GOOD: 0.000 ~ 0.220ppm

MODERATE: 0.221 ~ 0.660ppm

POOR: 0.661 ~ 2.200ppm

UNHEALTHY: 2.201 ~ 10.000ppm

In which cases is VOC generated?

VOC occurs mainly in household products such as:

- Paints and other solvents

- Wood preservatives

- Aerosol sprays

- Detergents and disinfectants

- Insecticides, fragrances and pesticides

- Combustion fuels such as volatiles

- Dry cleaning clothing

- Products with glue

Is PM not measured in the VOC measurement mode?

OLED display shows the VOC measurement value in the VOC mode.

To view all measurement results simultaneously, use the integrated display mode.

Or switch to PM (Particulate Matter) measurement mode to see PM2.5 & PM10 concentration.

Is the VOC value measured in the ICON mode or in the PM mode?

Measurements are being made, but the OLED display in the ICON or PM mode shows PM2.5 & PM10 value.

To view all measurement results at the same time, switch to the integrated display mode.

Or switch to VOC mode to see VOC result.

VOC levels are higher or lower when power is on

Due to the nature of the gas sensor, VOC or CO2 values can be measured slightly higher or lower when power is on, which is normal.

The longer the disconnection period is, the longer it may take to stabilize.

If you do not use it, you can keep it charged for more stable use.

VOC measurements are not displayed immediately

VOC and CO2 sensors require time to stabilize.

It takes around 15 ~ 60 seconds, and it usually shows the measured value in around 15 seconds.

How can I check that the PM2.5/PM10 measurement is working?

If there is a purifier, put it on the purifier outlet.

If the measured value is less than 10 units, it will work normally.

Another method is to rub a tissue on the suction side of the device to generate dust, which can lead to an increase in the PM10 value.

If you smoke, the level will go up tremendously.

However, smoking is harmful to your body, so please do not try it in this way.

PM value goes up if a humidifier is turned on

Basically, fine particles of water coming from a humidifier are perceived by optical sensors as fine dust, which is also seen in high-end equipment. We recommend that you turn off the humidifier and measure. Even on rainy or very humid days, PM measurement is a little higher on the same principle.

What is the PM sensor management method?

For accurate measurement and prolonged use, you can keep the sensor clean by strongly blowing the air intake part 2 ~ 3 times. When storing the device for a long time, please keep it away from dust and humidity. 

How long does the sensor last?

The PM sensor has a life span of 10,000 hours and can be safely used for more than 2 years on a regular basis. The life span of VOC or CO2 gas sensors is 10 years.

Can I charge the device with my own mobile phone or PC charger?

Yes, you can use the mobile phone fast charger due to the built-in high-speed charger protection circuit.

PM levels are different from smartphone application

The PM levels provided by the Meteorological Administration and Smartphone application are basically measured at more than 10m above the ground and are provided by a specific measuring station installed in a specific area. Our device measures the air quality just around you in real-time.

What is the WHO display mode?

Huma-i provides a display mode that meets the World Health Organization (WHO) recommendation criteria.

Especially infants and elderly people with weak immunity are strongly recommended to use the WHO mode.

What is the battery running time?

Huma-i basically uses a rechargeable lithium-polymer battery.

Assuming that you use it for 10 minutes each time, it can be used about 10 times when fully charged.

(It may vary depending on the battery condition.)

If you use a portable auxiliary battery, you can use it much longer.

In ICON mode, PM2.5 and PM10 are switching automatically

ICON mode automatically selects and displays Poor level between PM2.5 and PM10 values.

Looks like there is a scratch on the display

The protective film is attached to the display screen for product protection.

This film is a protective film to avoid scratches that may occur in the manufacturing process.

If you remove the protective film after receiving it, you will be able to see a cleaner screen."

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