There are a number of ways humidity causes damage in your building because its level is too high, as:

  • Look for signs of allergies from anyone in the building such as worsening hay fever sneezing or post nasal drip
  • Fog on indoor windows
  • Mold growth; moldy or dusty smell
  • Damp spots, e.g., on ceilings or walls
  • Peeling paint
  • Sweating on the basement floor or walls
  • Condensation on water pipes
  • Any collection of water or mildew
  • Decaying wood
  • Wet spots or water stains on ceilings

For most indications that the humidity is too high, the ‘symptoms’ manifest themselves over a long time, e.g., damp spots and peeling paint. For your assets, the saying goes ‘prevention is better than to cure’. Walls and windows have to be painted again, rotten wood has to be replaced, etc.

And even more important, this means that people inside the building have long suffered from humidity levels that are too high. For many people, it has deteriorated their feeling of well-being and worsened their productivity. It may also have triggered and worsened asthmatic and allergenic symptoms.

How to prevent indoor air gets too moist?

Check your indoor air quality and take care of the humidity. The EPA (Environmental Protection Agency) advises to keep humidity levels between 30–50%. Modern sensors like the AirGuard measure humidity, heat and TVOC and CO2 as well and give you a warning when humidity conditions are not optimal. So, you can open or close a window for instance.

Humidity is a measure of how much water or moisture there is in the air. Many people with asthma have more complaints when the air is humid. When people speak about humidity, they actually talk about ‘relative humidity’. This is the percentage water in the air, compared to the maximum amount of water the air can hold given the current temperature. When the weather is hot, the air can contain more water than cold air. So, the same relative humidity of say 60% might feel more wet on hot days than on cold days. How does humdity affect asthma?

Importance of humidity

Many people find a humidity of 30-60 percent comfortable. During the hot summer months, many people feel that a humidity level of 55% is comfortable. Above this level, the air is considered humid. Because sweat doesn’t evaporate enough to cool you off, you feel hot and sticky when the air is humid. Above the level 65% is felt as oppressive.

But also: humid air is harder to breath. That can be a problem if you have asthma. Many people with asthma feel that a humidity level above 65% may worsen their symptoms of asthma. When you have asthma, it is more difficult to pull enough air into the lungs, because your airways become narrow. This may cause feeling of shortage of breath or wheezing and coughing.

3 Ways Humidity worsens Asthma

Allergens, chemicals and strong scents are common triggers for people who suffer from asthma. But high humidity can be also just as troublesome.

People with asthma have inflamed airways that are sensitive to things that may not bother other people. That’s why humidity, and all that comes with it, can be a problem for people with asthma. Here are some reasons why.

  • Humid air feels harder to breathe in
  • Humidity may worsen air quality
  • Humidity can mean very high temperatures

Humid air feels harder to breathe in

Hot, humid air may feel heavier and denser and thus harder to breathe in. Besides, humidity may activate sensory nerve fibers in the airways. These C-fibers may narrow the airways and stimulate coughing, which makes it difficult to breathe. Besides, when heat and humidity make the air harder to breathe, the body temperature can go up. This causes sweat, which can lead to dehydration. This can lead to make you breathe faster. These factors may trigger asthma symptoms.

On the other hand, when the air is very dry -a relative humidity is less than 15%- it may also lead to coughing when you’re asthmatic. When the air is very dry, the mucous membranes of the respiratory system may dry out. These membranes line your lungs and respiratory system. This leads to an increased risk for infections from viruses: due to the decreasing natural defense from influenza or the common cold virus. Dry mucous membranes may aggravate allergy symptoms and worsen asthma symptoms (most asthmatics have also allergies).

Humidity may worsen air quality

Humidity can also trigger asthma because moist increase levels of mold, dust mites, ground-level ozone. Those are known as asthma triggers.

When the humidity level is higher than 50 percent, mold might begin to grow. Mold is often found at damp places. If you are sensitive for mold, it may trigger your asthma.

Dust mites are also a problem inside when humidity is high. Dust mites live in furniture, carpets, etc.  If the humidity in your home is higher than 50 percent, dust mites thrive and multiply themselves. Their dead bodies and waste may trigger asthma.

Heat and Humidity may also lead to stagnant air from pollutants (like ozone), allergens (dust, mold, dust mites, pollen) and smoke. This may also trigger asthma symptoms.

Asthma worsens feelings of well-being and productivity

For people suffering from asthma, poor humidity levels don’t affect only the feeling of well-being. It has effects on your productivity. An international study in the Journal of Asthma and Allergy shows: “The average percentage of work hours missed in a single week due to asthma symptoms was 9.3%, ranging from 3.5% (UK) to 17.4% (Brazil). Nearly three-quarters of patients reported an impact on their productivity at work caused by asthma. Overall work productivity loss (both time off and productivity whilst at work) due to asthma was 36%, ranging from 21% (UK) to 59% (Brazil). When asked how asthma made participants feel at work, many respondents highlighted how their respiratory symptoms affect them. Tiredness, weakness and mental strain were also identified as particular challenges, with respondents describing concerns about the perception of colleagues and feelings of inferiority”

Control your humidity level

Humidity levels can worsen asthma in 3 ways. It doesn’t only affect the feeling of well-being, but also productivity. Thus, it is very important for offices, schools, institutions etc. to assure that humidity levels are being kept on levels where children, employees, visitors feel most comfortable. Smart sensor solution like the AirGuard help to monitor the indoor air quality.

In a previous blog we already talked about Volatile Organic Compounds. Volatile organic compounds are organic chemicals that become a gas at room temperature. There are thousands of VOCs and a multiple of VOC’s are at the same time present. What are TVOCs?

What are Volatile Organic Compounds?

As said, these are organic chemicals that become a gas at low temperature levels. Or more practically put: they become gas at room temperature.

Or more scientific:

Volatile organic compounds, or VOCs are organic chemical compounds whose composition makes it possible for them to evaporate under normal indoor atmospheric conditions of temperature and pressure

They have a low boiling point, which results in high vapor pressure. This causes many molecules to evaporate or sublimate from the liquid or solid form of the compound to enter the surrounding air. This is called volatility: the ease of a substance to vaporize at a given temperature.

The EPA remarks: “Normal indoor atmospheric conditions of temperature and pressure used here refers to the range of conditions usually found in buildings occupied by people. Thus, depending on the type of building and its geographic location, the temperatures could be from the mid-30s (in Fahrenheit degrees) to the 90° F range and the pressure could be from sea level to the elevation of mountains where buildings might be located. This is not to be confused with “Standard Temperature and Pressure,” often used in analysis and presentation of scientific studies, but defined variously by different authorities. The most used, although not universally adopted, definitions are those of the International Union of Pure and Applied Chemistry (IUPAC) and the National Institute of Standards and Technology (NIST). IUPAC’s standard is a temperature of 0° C (273, 15 K, 32° F) and an absolute pressure of 100 kPa (14.504 psi), NIST’s definition is a temperature of 20° C (293, 15 K, 68° F) and an absolute pressure of 101.325 kPa (14.696 psi).”

Some examples of VOC’s are:

  • Benzene
  • Ethylene glycol
  • Formaldehyde
  • Methylene chloride
  • Tetrachloroethylene
  • Toluene

But in fact, there are thousands of VOC’s. And they are everywhere. They occur naturally or may be human-made.

They can be generated from many products, such as paints, glues, fossil fluids. Some everyday examples you might not even realize: terpenes released when you peel an orange. Or the squalene from human skin oil. When they react with ozone, they form even more toxic molecules.

Some VOCs are immediately dangerous to the environment or humans, but mostly are not. Other VOCs are non-hazardous. If a VOC has impact on your health depends on indoor concentration, time spent indoors and hazardousness of the VOC.

If VOCs are harmful, these are mostly long-term health effects. However, there is still much research to be done. And as stated in the previous article, they may not be harmful for your health, but may lessen your sense of well-being and productivity.

KBO-PCOB pleit voor laagdrempeliger testen en ventilatiecheck in verpleeghuizen. Dit om de verspreiding van Covid-19 tegen te gaan. Wij denken dat het belangrijk is om continue luchtvochtigheid, temperatuur, volatiele deeltjes als CO2 te meten.


“Daarnaast worden niet alleen binnen scholen maar ook binnen verpleeghuizen vraagtekens gezet bij de betrouwbaarheid van de ventilatiesystemen als het gaat om verspreiding van aerosolen via zo’n systeem. KBO-PCOB dringt er daarom op aan dat ventilatiesystemen bij verpleeghuizen voor 1 oktober gecheckt worden door uitbreiding van de taken van het Landelijk Coördinatieteam Ventilatie op Scholen. Vanderkaa:“In verpleeghuizen verblijven kwetsbare mensen, daar moet de luchtkwaliteit goed zijn. Het mag niet zo zijn dat bewoners gevaar lopen door ondeugdelijke ventilatiesystemen.”” (KBO-PCOB website)

Belang luchtkwaliteit: continue check

Wij denken dat het wenselijk is dat de luchtkwaliteit continue gecheckt wordt. Niet alleen vanwege Covid-19. Ook om te zorgen dat de luchtkwaliteit goed is vanwege de kwetsbaarheid van oudere mensen.  Om zo de verspreiding van andere virussen zo goed mogelijk tegen te gaan. Daarnaast kan een slecht binnenklimaat leiden tot klachten als niezen, hoofdpijn, duizeligheid. Ook kunnen allergieën en astma worden verergerd. Een oplossing als Airmex meet zowel luchtvochtigheid, temperatuur, volatiele deeltjes als CO2.

More than half (51 percent) of all elementary school in the Netherlands sent one or more classes home last week because of Covid 19.

“The AVS estimates that nearly 220,000 elementary school students were quarantined at home, out of a total of about 1.6 million students. According to the poll, 1.3 percent of elementary schools were forced to close completely because of corona attacks ” (Metro Nieuws)

Staffing shortage

Metro continues: “According to President Petra van Haren, the pressure is on school leaders. ‘They are constantly looking for substitutes to prevent children from having to go home,” she says. Of the school leaders who participated in the survey, 60 percent had to use substitutes last week. “Because of the staffing shortage, that’s not easy,’ Van Haren says.”

1 Child infected, whole class at home

If in a class a child or teacher is infected with the coronavirus, the entire class must go home. For at least five days as a precaution. Unless they work in small groups that are not close to each other. In most elementary schools, however, this does not happen. Many schools find it practically unworkable. Those who get tested five days after contact with the infected child and get a negative result may return to school. Children who do not test may return to school only after ten days, provided they have no symptoms.

How sensors help

Sensors like the Airmex help monitor air quality to ensure that the Covid 19 virus is as inactive as possible. And to ensure that temperature and humidity levels are optimal for a pleasant stay and an optimal environment for performance. They also measure CO2. CO2 is another important air quality parameter.

For many, Covid-19 was an eye-opener for the importance of indoor air quality. One of the most important pollutants indoors is Carbon Dioxide (CO2). Children spend a large portion of the day at school. Research shows that there are high levels of CO2 in many classrooms. Those high CO2 levels affect the sense of wellbeing, and even worse: school grades.

CO2 levels in school too high

The Western Cooling Efficiency Center (UC Davis ) shows: “Research from around the world shows there are high CO2 levels in many classrooms. For example, in a 2019 study, researchers found that about 85% of 94 recently installed HVAC systems in California K-12 classrooms did not provide adequate ventilation.”They investigated 104 classrooms in California. 85% did not have proper ventilation, which means increased levels of CO2.

In indoor testing between 2010 and 2015, 43% of Toronto schools had a CO2 concentration above 1000 ppm.

Why does the last hour always take ages?

bored child classroom school high co2 levels airmex

After sitting the whole day at school, the last hour seems to take ages. Always getting a headache. You can’t concentrate and think properly. Probably the cause it isn’t the teacher. It’s you, the students.

Students and the teacher breathe oxygen into the lungs as energy. The oxygen sticks to red blood cells and is transported to organs and muscles, so your heart can pump, you can think with your brain and contract your muscles. This ‘burning’ process of oxygen turns into carbon dioxide (CO2) and water vapor, which are released back into the environment.

When the ventilation is poor, the ‘used’ air will not dilute enough with ‘new’, fresh air from outside. So, especially with many people in a closed room (like a class-room) and the ventilation is poor, the oxygen in this room gets more and more replaced by CO2.

CO2 itself is not toxic. In fact, it’s a natural part of the atmosphere. It’s the fact that it’s replacing the oxygen concentration because a high concentration of CO2 is toxic. (That’s why CO2 is called an ‘asphyxiant gas’:  a nontoxic or minimally toxic gas which reduces or displaces the normal oxygen concentration in breathable air.)

How CO2 levels affect school results

Due to the fact that the student inhales less oxygen, less oxygen goes to the brains. If there’s too much CO2, students may find it hard to pay attention to the teacher. Or concentrate on tests. Or stay awake at all. Besides, high levels of CO2 may affect the ability to make decisions. So, without even realizing yourself, high CO2 can damage your productivity and your school results. Besides, when we think of gasses, we think smell will warn us. However, CO2 is odourless.

CO2 might also cause physically complaints:

  • Headache
  • Feeling dizzy or nauseous
  • Tired
  • Trouble breathing
  • Worsen asthma symptoms, allergies and lung health

You yourself might feel complaints, while the student next to you doesn’t feel anything. How you react, depends on several factors – such as: your own health, heredity, personal habits as smoking and drinking, use of medicine, previous exposure to chemicals.

What are high CO2 Levels?

As said, CO2 is a gas that is a natural part of the air. CO2 is measured in so-called parts per million (ppm). Outside, the normal level is about 400ppm. Otherwise said: per 1 million parts in the air, 400 of them consists of carbon dioxide. Before the industrial revolution, this level was about 280 ppm.

In general, occupied rooms with good ventilation have 400 – 1,000ppm. However, from 800 ppm, people may begin to suffer, maybe without knowing themselves.

From 1,000 to 2,000 ppm, people get complaints of drowsiness and poor air. When the level is between 2,000 to 5,000 ppm: complaints of headaches and sleepiness. The air becomes stale, stagnant and stuffy. As a consequence, people have lower concentration and loss of attention. An increased heart rate and slight nausea may also be the case.

From more than 5,000 ppm, the air becomes toxic and more serious effects can occur.

Common HVAC Issues resulting in high CO2 levels

In modern times, schools and other buildings are built with comfort in mind: to create a comfortable, warm space, thanks to isolation and… However, this comfort may come with a downside. Because a room is too closed from the outside world, this may result in the lack of replacing the air inside with fresh air from outside.

In the California study, 85% of the classrooms did not provide adequate ventilation. ‘“We were shocked,” said Wanyu Rengie Chan, one of the lead researchers of the study, “We were not expecting it.”’ They were shocked, because it involved classrooms with newly installed HVAC.

What are HVAC issues, causing high CO2 levels?

  • Problems with installation of HVAC systems
  • Incorrect HVAC systems purchased
  • Incorrect controls and thermostats
  • No follow-up testing after installation
  • Poorly-maintained filters

(Source: Ventilation Rates in California Classrooms study)

CO2 monitoring helps

Children spend many hours indoors at school. Therefore, it is important to have a good indoor air quality. For the feeling of well-being for the children and teacher, but also for the children’s grades. You can measure the CO2 with a CO2 meter, or a sensor which combines the monitoring of CO2 with temperature, humidity and Volatile Organic Compounds, for instance ASN’s Covid-AIRMEX.

Advanced Solutions Nederland’s AIRMEX employs the Nordic Thingy:52 to provide easy-to-use environmental sensors and wireless connectivity for pandemic management

Nordic Semiconductor today announces that Amersfoort, Netherlands-based, Advanced Solutions Nederland (ASN), an IoT and Industrial IoT (IIoT) sensor technology company, has selected the Nordic Thingy:52 Bluetooth® 5.2/Bluetooth Low Energy (Bluetooth LE) compact multisensor prototyping platform to provide the wireless connectivity and processing power for its ‘AIRMEX’ indoor environmental monitoring solution. AIRMEX is an AI-powered temperature, humidity, CO2, and TVOC (Total Volatile Organic Compounds) sensor platform that enables, for example, workplaces, schools, restaurants, and places of worship to monitor and regulate indoor environmental conditions to minimize the risk of the airborne spread of SARS-CoV-2, the virus that causes Covid-19, as well as promote overall healthy living and working conditions for occupants.

This article is retrieved from Nordic Semiconductor: original publication, 04Mar 2021 Oslo, Norway)

Recommendations for air-quality improvement

The ceiling- or wall-mounted device employs the Nordic Thingy:52’s integrated humidity, temperature and gas sensors to provide continuous, near real time monitoring of environmental air quality. Running ASN’s ‘Chameleon’ AI algorithmic application software—developed and ‘trained’ to promote indoor air conditions that specifically minimize the risk of the spread of Covid-19—the Nordic Thingy:52’s powerful 64MHz, 32-bit Arm® Cortex® M4F processor with floating point unit (FPU), allows the solution to process the data from all four sensor. The applications software does more than simply measure and display temperature and humidity readings, rather it provides real-time updates and recommendations for air quality improvement.

The Nordic Thingy:52 integrates many useful sensors which along with its Bluetooth LE connectivity provides a cost-sensitive solution

Dr Sanjeev Sarpal, ASN

The data is relayed to a Bluetooth 4.0 (and later) smartphone, where from the partner ‘Covid-AIRMEX’ Android app, the user is provided with immediate feedback on overall air quality and recommendations on how to improve the environmental conditions. For example, “increase dehumidifier settings” to reduce humidity, or “very high gas levels present” to indicate inadequate ventilation. In the absence of a smartphone, AIRMEX has a multi-coloured LED indicator to provide users with an immediate overview of current environmental conditions.

AIRMEX uses a standard 1400mAh Li-ion battery to provide approximately six weeks battery life in standard operation, thanks in part to the ultra-low power characteristics of Nordic’s nRF52832 System-on-Chip (SoC) at the heart of the Nordic Thingy:52. The nRF52832 has been engineered to minimize power consumption with a fully-automatic power management system that reduces power consumption by up to 80 percent compared with the nRF51 Series. 

Multisensor prototyping platform

The Nordic Thingy:52 is a compact multisensor prototyping platform designed to help wireless IoT sensor projects get off the ground quickly. The product is a fully tested and working wireless sensor platform that can be used by a developer with no high-level development tools or firmware coding expertise to rapidly design wireless IoT devices and associated mobile device and Internet apps. The Nordic Thingy:52 is based on the nRF52832 SoC. The SoC features a 32-bit, 64MHz Arm® Cortex™ M4 processor with a 2.4GHz multiprotocol radio (supporting Bluetooth 5.2, ANT™, and proprietary 2.4GHz RF protocol software) featuring -96dB RX sensitivity, and 512kB Flash memory and 64kB RAM. The SoC runs Nordic’s S132 SoftDevice—a Bluetooth 5-certifed RF software protocol stack for building advanced Bluetooth LE applications—it can support up to 20 concurrent connections in a variety of Bluetooth LE role combinations.

“The Nordic Thingy:52 integrates many useful sensors which along with its Bluetooth LE connectivity provides a cost-sensitive solution,” says Dr Sanjeev Sarpal, Director AI Data Algorithms & Analytics at ASN. “The well written firmware libraries also helped our developers get up and running in a fraction of the time rather than starting a development from scratch, while the reference designs and good documentation were equally an important consideration in selecting the solution.”

Since Covid-19, there is even more attention for indoor air quality. It might be possible that poor ventilation may contribute to the spread of the coronavirus. In any case, some contaminations are already known to decrease indoor air quality. Poor Humidity, Temperature, CO2 and TVOC conditions may be the cause. It influences productivity, leads to less sense of comfortability and well-being and can cause sickness. Beat poor indoor Air Quality with data science.

Indoor concentration of pollution often 2 to 5 times higher than outdoor

Did you ever wonder where you are most exposed to air pollution? Somewhere outside, you say? Wrong, you breath the most polluted air… indoors! Research shows, that people spend 90% of their time indoors. Isolation and modern heating have brought us comfy, warm indoor environments: home, work, recreation, etc., with no cold air coming from under the doors or through windows. However, in many buildings there is a downside. With the tightly enclosed indoor environments, pollution caused indoors or coming from outside has no opportunity to mingle with fresh air. For viruses, heat and certain levels of humidity are perfect environments to stay active.

Pollution may lead to:

  • Irritation of the throat, nose and eyes, such as a dry throat
  • Headaches, dizziness, and fatigue
  • Respiratory diseases, heart disease, and cancer


Besides, the Covid-19 virus is spreading. Since Covid-19, there is a lot of attention for indoor door quality. Besides social distancing, wearing a mask and washing your hands, good ventilation is one of the measures to reduce the risk of infection indoors.

CO2 and TVOC measurement for well-being and productivity

Indoor air quality is depending on… inside and outside factors… Besides temperature and humidity, 2 other factors for indoor air quality are CO2 (Carbon Dioxide) and TVOC (Total Volatile Organic Compounds).

CO2 originates when people breathe, sweat and in all other occasions where there is a burning process involved. CO2 concentration has to remains less than 800 PPM. At higher concentrations people begin to suffer.

Besides, many substances are also source of contamination like cleaning products, paints, varnishes, furniture and glues. These are called Volatile Organic Compounds (VOC’s). Immediate complaints may be symptoms headaches, eye, nose and throat irritation and bad odors. Long term exposure may lead in large doses can damage liver, nervous systems and kidneys.

The impaction of the combination of CO2 and TVOC is even larger. A study shows: “On average, cognitive scores were 61% higher on the Green building day and 101% higher on the two Green+ building days than on the Conventional building day.” 

Data Science helps you to maintain healthy and productive air quality

Temperature and Ventilation are more important than ever. Regulate your temperature to obtain a comfortable and healthy environment. Replace bad air with fresh air from outside. By ventilation or just by opening a window.

When you’re busy, keeping an eye on working conditions may be easily ignored. Sensors which measure temperature and humidity like the Airmex help you to maintain your indoor air quality such, that the risk of spreading the viruses is as least as possible They also help you to keep a comfortable, healthy and productive environment. It warns you on an app when you should adjust your room temperature or when you should ventilate. Those signals are based on data science and based on guidelines as the ASHRAE Standard 55 – Thermal Environmental conditions for Human Occupancy.

Find out how the Airmex can help you.

You have probably experienced a ‘sick building’ yourself. You may not feel well in a room or building, such as irritated eyes or nose. Without knowing exactly where this feeling comes from. Or you experience that you suddenly feel better when you leave that room or building. The term “sick building syndrome” (SBS) is first used in the 1970s. It describes a situation in which reported symptoms among a population of building occupants can be temporally associated with their presence in that building. Typically, though not always, the structure is an office building.

Symptoms of Sick Building Syndrom (SBS)

In short: more co-workers experience the same complaints when they are in the building or in the same parts of a building. Most of the times, complaints disappear or lessen when people leave those buildings or parts.

Symptoms of a Sick Building Syndrom can include:

  • eye, nose and throat irritation (irritation of mucous membranes)
  • lethargy or fatigue
  • headache, dizziness, nausea
  • inability to concentrate
  • sensitivity to odors
  • general malaise-complaints

Indication that the complaints are caused by Sick Building Syndrome are:

  • Are problems temporally related to time spent in a particular building or part of a building?
  • Do symptoms resolve when the individual is not in the building?
  • Do symptoms recur seasonally (heating, cooling)?
  • Have co-workers, peers noted similar complaints?

Difference between Sick Building Syndrome and ‘building related illness’

It is important to distinguish the ‘Sick Building Syndrome’ from building related illness. Building related illness means that symptoms of illness can be directly related to specific airborne building contaminants. Examples are Legionnaire’s Disease or hypersensitivity pneumonitis.

What causes sick building syndrome?

The EPA distinguishes 4 causes of or contributing factors for sick building syndrome (Indoor Air Facts No. 4 (revised) Sick Building Syndrome):

  • Inadequate ventilation
  • Chemical contaminants from indoor sources
  • Chemical contaminants from outdoor sources
  • Biological contaminants

Inadequate ventilation

Due to the fact that outdoor air ventilation is inadequate to maintain the health and comfort of the people inside the people. Another reason for inadequate ventilation may occur if heating, ventilation and air condition (HVAC) systems do not effectively distribute air to people inside the building

Chemical contaminants from indoor sources

Most of the indoor pollution comes from sources inside the building. For example: adhesives, carpeting, upholstery, manufactured wood product, copy machines, pesticides and cleaning products may emit volatile organic compounds (VOCs), including formaldehyde. Tobacco smoke may also be a source, if smoking is still allowed inside the building. Another source may be combustion products, due to unvented gas and kerosene heaters, gas stoves, woodstoves and fireplace

Chemical contaminants from outdoor sources

For example, motor vehicle exhausts which enters the building

Biological contaminants

Examples are bacteria, molds, pollen, viruses and animal droppings

It’s possible that the underlying causes of the above-mentioned factors are:

  • Poor ventilation, due to poor design, maintenance or operation. The ventilation itself can be a source of irritants.  Besides, interior redesign such as rearrangement of offices may cause inefficient functioning of the systems.
  • These elements may act in combination. Where some pollutants themselves are at a very low level, the way they react on each other may cause health effects
  • Elements may supplement other complaints such as inadequate temperature, humidity, or lighting. High humidity may contribute to biological pollutant problems. On the other side, levels below 20 or 30 percent may heighten the effects of mucosal irritants and may be irritating itself
  • Other factors may also play a role, such as stress, noise, insufficient light.

Solutions like the Airmex can help you to create a safe and healthy environment for work, meeting and living. It monitors your air quality and alarms you when the air quality has dropped below acceptable levels

Vanaf 1 maart gaan middelbare scholen weer open na de lockdown vanwege Covid-19. Het basisonderwijs en de kinderopvang zijn vanaf 8 februari open gegaan. Echter: nog niet alle scholen blijken te voldoen aan de richtlijnen voor ventilatie. Dit terwijl goed ventilatie mogelijk de verspreiding van het coronavirus verminderd. En zeker draagt goede ventilatie bij tot het welzijn en is gezonde lucht beter voor leerprestaties

Scholen gaan weer open

Het basisonderwijs en de kinderopvang is vanaf 8 februari weer open gegaan. Vanaf maandag 1 maart gaan de middelbare scholen en mbo-instellingen voor alle leerlingen weer open: op 23 februari heeft het kabinet besloten dat alle leerlingen en studenten minimaal 1 dag per week fysiek naar school gaan. Dit om meer perspectief aan jongeren te bieden: fysiek onderwijs draagt bij aan het welzijn en is beter voor leerprestaties.

Ventilatie schoolgebouwen: 777 schoolgebouwen voldoen nog niet

Het Landelijk Coördinatieteam Ventilatie heeft onderzoek uitgevoerd naar alle scholen (primair en voortgezet onderwijs) in hoeverre scholen voldoen aan de ventilatienormen. Hiervoor heeft zij in september een vragenlijst verstuurd.

Uit dit onderzoek blijkt dat nog niet alle schoolgebouwen aan de wettelijke normen voor ventilatie voldoen:

Onderzoek kwaliteit binnenlucht. De volledige vraag luidt: “Heeft er in het schoolgebouw per ventilatiesysteem een onderzoek plaatsgevonden naar de kwaliteit van de binnenlucht op basis van de capaciteit voor luchtverversing, een permanente CO₂-meting, of de indicatieve meetmethode? Voldoet het schoolgebouw aan de normen die voortkomen uit het Bouwbesluit en aanvullende richtlijnen?”

  • In september 2020 is door 7340 ingevuld. Uitgaande van 9331 is dit 79% van het totaal aantal scholen.
  • 777 scholen geven aan dat zij niet voldoen aan de richtlijnen. Dit is 11% van de totale respons van 7137 schoolgebouwen. Oftewel 22% van de scholen aangeven dat het onderzoek heeft plaats gevonden. Hier zijn technische aanpassingen nodig.
  • 2952 scholen geven aan dat zij voldoen aan de richtlijnen. Dit is 78% van de scholen waarbij het onderzoek heeft plaats gevonden.  Hierbij wordt wel bij 325 metingen opgemerkt dat men nu voldoet, maar zich zorgen maakt over de wintermaanden.
  • 2678 scholen geven aan op korte termijn onderzoek zullen uitvoeren, bijvoorbeeld wanneer er CO2 meters beschikbaar zijn
  • 730 scholen geven aan dat ze het onderzoek niet kunnen uitvoeren. “Als redenen om het onderzoek niet uit te voeren geeft men voor 128 gebouwen het onderzoek ‘later, op een nog niet bekend tijdstip uit te voeren’ en wordt voor 155 gebouwen opgemerkt dat geen CO₂-meters beschikbaar zijn.”

Bij het niet hebben kunnen uitvoeren speelt ook mee dat het onderzoek op korte termijn heeft plaats gevonden: sommige scholen hadden geen technici beschikbaar of gaven het onderzoek geen voorrang.

Scholen blijven open als ventilatie niet goed is

Schoolgebouwen moeten voldoen aan de wettelijke normen voor een gezond binnenklimaat conform het Bouwbesluit en de aanvullende richtlijnen.  Hiervoor stelt het kabinet € 360 miljoen beschikbaar om scholen te helpen de ventilatie op orde te krijgen.

Coronavirus en ventilatie

Op de site van de Rijksoverheid:

“Ventilatie en verspreiding van het coronavirus

  • Overdracht van het virus vindt vooral plaats bij verspreiding van grote druppels, via bijvoorbeeld hoesten en niezen, aldus het RIVM.
  • Het is op dit moment onduidelijk of kleine druppels, de zogenaamde aerosolen, een relevante rol spelen bij de overdracht van het virus. 
  • Ventileren en luchten helpen om luchtweginfecties te beperken.
  • Het RIVM adviseert in ieder geval de bestaande regelgeving en richtlijnen op het gebied van ventilatie en luchten te volgen. Dat geldt ook voor scholen. Bovendien leren leerlingen het beste in een prettige omgeving met gezonde lucht.
  • Het is onbekend in welke mate ventilatie helpt om de verspreiding van het virus daadwerkelijk tegen te gaan.”

Belang van ventilatie op welbevinden en leerprestaties

Sowieso is het coronavirus niet de enige reden voor ventileren:

  • Ventilatie kan helpen gezondheidsklachten als hoofdpijn te verminderen
  • Leerlingen leren het beste in een prettige omgeving met schone lucht. 

Het advies van de GGD is dan ook om scholen niet te sluiten bij onvoldoende ventilatie. Ook het kabinet noemt het belang van fysiek onderwijs voor het welzijn en leerpresaties in haar besluit om middelbare scholen en mbo-instellingen weer te openen, ondanks stijgende covid-19 aantallen.

Scholen die niet aan de normen voldoen, krijgen hierover nu al advies van de GGD, de arbodienst en Kenniscentrum Ruimte OK. Ook kunnen scholen gebruik maken van de handleiding die het Coördinatieteam heeft opgesteld. Zoals nemen van maatregelen als het plaatsen van roosters en het aanvullend luchten in pauzes.

Oplossingen als de Airmex kunnen helpen om de luchtkwaliteit in een schoolgebouw te bewaken door niet alleen CO2, maar ook temperatuur, luchtvochtigheid en volatiele deeltjes te meten. Dit voor een gezonde en prettige leeromgeving te creëren.