Indoor Air Pollution

Over the last 5 years there has been a huge upsurge of concern in the UK about the impact of polluted air on people’s health. Most of this concern has been focused on outdoor air – particularly in major conurbations. In the UK alone, polluted air is responsible for around 40,000 premature deaths a year – and worldwide, the number is estimated at over 6.5 million.

Indoor air is less polluted, right?…………wrong!

We spend up to 90% of our time indoors – at home, at work, at indoor leisure activities etc….often in the belief that indoor air is less polluted and healthier.
But is it?
In fact, indoor air can be over 5 times more polluted than outdoor air, due to human activity, dust, cleaning agents, air fresheners, paints, polishes, chemicals, deodorisers, pesticides, plus “off-gassing” of volatile organic compounds from many types of fabrics, floorings, furniture, adhesives. Add to that, inadequate ventilation and polluted air from outside…..

Your right to breathe healthy air - PLEASE READ THIS - IT'S ABOUT YOU

We all have a very high level of control over what we eat and drink. But when it comes to the air we breathe, we have virtually none. And yet, adults breathe around 11,000-17,000 litres of air per day, depending on activity. We should know about what we breathe, especially when we’re indoors and have no alternative but to breathe the air we’re supplied with. 

There is now much evidence* that polluted air causes major health problems; it inhibits the physical and mental development of children and can even bring about premature death. It has a direct impact on our short- and long-term health and the way our brains and bodies perform.

So when you’re at work or having a workout at your favourite gym, or in your local supermarket how do you know if you’re being supplied with unpolluted air? You don’t – because the quality of the air is almost certainly not being monitored for pollutants.

Your employers or your gym manager might say “Well, we’ve never had any complaints” – but that’s not the point! They don’t know if the air you are forced to breathe in those buildings contains pollutants or not.

For example, without monitoring, no one would know if the air in a city office is polluted with harmful particulates, ozone, volatile organic compounds and high levels of carbon dioxide. And in a crowded gym, the carbon dioxide levels can rise dramatically making your body and lungs work hard to extract oxygen from carbon dioxide laden air.

Arguably, employers have a responsibility to supply healthy air to their employees. The only way they can prove that they are fulfilling that obligation is to monitor the air and display the data on the video screens and/or their website.

And without monitoring indoor air quality how can schools reassure you that the indoor air your children breathe is healthy?

Healthy air? It’s your right, your family’s right.

*For example:
Every breath we take: the lifelong impact of air pollution – Published February 2016 by the Royal College of Physicians and the Royal College of Paediatricians and Children’s Health.

uHoo shows you in real time the level of pollutants in the air around you – at home and at work, – and empowers you to take action to improve air quality.

For the UK, uHoo monitors have NINE environmental and pollutant parameters – more than any other in its class – click on the list below.

Temperature °C

Important not only for reasons of comfort but also because it can have a direct influence on the brain’s cognitive function. Unless acclimatised to hot or cold conditions, some people may find it difficult to concentrate or work in room temperatures above 25°C or below 15°C. 19-21°C is regarded as optimal for offices and 21°C for home comfort. In certain ratios to humidity, temperature can have a direct influence on the development of mould in buildings.

Humidity  % RH

The ideal range for indoor humidity is around 45-55% RH.

Low humidity is a characteristic of winter air as cold air cannot carry as much moisture as warm air.

Many commercial buildings are maintained at low humidity, sometimes as low as 20% and this may contribute to Sick Building Syndrome (SBS)

Low humidity i.e. below 35% can cause: –

  • Dry Nasal Passages:In dry air, mucus membranes can dry out quicker than the moisture can be replenished by the body. This can manifest itself as dry and even painfully cracked sinuses. It can become so severe that the cracked sinuses bleed. This is partly why some people experience nosebleeds during the drier, cooler autumn and winter months.
  • Dry eyes: You have a complicated system that keeps your eyeballs wet with tears. Low humidity can cause the tears to evaporate quicker than the body can make them – resulting in dry eyes which can irritate and even be painful.
  • Sore or Itchy Throat: The same process that is drawing moisture from the nasal passages can also affect your throat.
  • More Illness: As the nasal passages dry out from low humidity, the body’s ability to trap and filter out viruses and microbes that cause illness is impaired. When the sticky mucus membranes of the nasal passages lose their ability to “filter”, more microbes can pass through. Even worse, as the mucus membranes dry and crack, they provide a direct path to the bloodstream for pathogens. Coupled with the fact that airborne viruses survive better in low humidity, this is why ‘flu is so prevalent during the winter.
  • Dry Skin: Itching is the most common symptom and for those with eczema or sensitive skin, the problem can be more pronounced. Beyond simple itching, persistent dry skin can actually lead to tiny cracks and even bleeding. Like the cracking of sinuses, cracked skin again opens the body up to greater exposure to microbes and illness.
  • Chapped Lips:This is likely. It’s the least harmful but most common symptom of low humidity.
  • Increased Static Electricity: Offices and other indoor environments with a low humidity (below 35%) are prone to electrostatic discharge (ESD). ESD is defined as the sudden flow of electricity between two objects of opposite charge. One all-too-common example of ESD is walking across a carpeted area during the winter and touching a doorknob, at which point you may notice a slight shock.

ESD is more common in environments with low humidity. Normally, the airborne moisture helps to dissipate static electricity. Water is conductive, which allows electricity to travel freely throughout the air, minimising electrostatic build-ups. If there’s not enough moisture in the air, electricity will accumulate at various points and discharge when an object of opposite charge is nearby.

Static electricity may not cause injury or health concerns, but it can do considerable damage to delicate computer components.

High Humidity

  • Depending partly on air temperature, Relative humidity at over 60% creates ideal conditions for the development and growth of mould and other allergens, particularly dust mites.
  • The physical problem with high humidity making us feel hotter is not just that we are more uncomfortable, but that our core temperature is actually rising, and our bodies compensate by working harder and harder to cool us down. When sweating doesn’t work to cool us down and we continue to heat up, overheating results, which causes loss of the water, salt, and chemicals that the body needs.

Nitrogen Dioxide NO2

  • Is released into the atmosphere when fuels are burned – for example, petrol or diesel in a car engine, or natural gas in a domestic cooker, central heating boiler or an electricity power station. NO2 can severely affect our health.
  • There is evidence that high levels of it can inflame the airways in our lungs and, over a long period of time, affect how well our lungs work.
  • People with asthma and other pulmonary conditions are particularly affected.
  • Natural gas cookers, widely used in the UK, can contribute to poor indoor air quality, especially when used without an extractor. This why kitchens with gas cookers are required, at minimum, to be vented to the outside by window, door or open vent – convenient in summer but much less so in winter!
  • Natural gas cookers emit nitrogen dioxide (NO2), carbon monoxide (CO), and in certain conditions, formaldehyde (HCHO) – each of which can exacerbate various respiratory and other health problems.

Particulate Matter PM2.5

  • This refers to invisible solid or liquid particles in the air, smaller than 2.5 microns (that’s just one 400th of a millimetre).
  • Depending on the source, these particles can be toxic and/or carcinogenic.
  • They can exacerbate lung and heart conditions, significantly affecting quality of life.
  • Children, the elderly and those with predisposed respiratory and cardiovascular disease, are known to be more susceptible to the health impacts from PM2.5 pollution.
  • The particles can be carried in the atmosphere for days after being created or emitted for example from industrial processes, electricity generating stations, vehicle car exhaust fumes – and even in the home – tiny fragments and fibres from carpets and furnishings, pet hair and dander, human skin, smoke particulates from cooking…and more. See the dust that settles on household surfaces? That consists entirely of particulate matter of one kind or another!
  • According to the World health Organisation “There is no evidence of a safe level of exposure or a threshold below which no adverse health effects occur.”
  • Human-made sources of PM2.5 are more important than natural sources, which make only a small contribution to the total concentration.
  • Within UK towns and cities, emissions of PM2.5 from road vehicles are an important source. Consequently, levels of PM2.5 close to roadsides are often considerably higher than those in background locations.
  • In some places, as indicated above, industrial emissions can be an extremely important source of PM2.5, as can the use of non-smokeless fuels for heating and other domestic sources of smoke such as bonfires.

Carbon Dioxide CO2

  • Carbon Dioxide CO2 is naturally present in fresh air at a concentration of 0.03-0.045% or between 300 and 450 parts per million (ppm).
  • Indoors, the primary source of CO2 is from people where we all inhale air to extract oxygen and exhale carbon dioxide as waste.
  • If a crowded indoor space is not adequately ventilated, carbon dioxide can build up to levels where people start to feel sleepy, lethargic; have difficulty in concentrating and may even experience nausea, vomiting, dizziness, headache, and rapid breathing.
  • The healthy maximum concentration of CO2 is 1000ppm (parts per million), and should never go above 1500ppm. However, a recent study by the Harvard Medical School has suggested that cognitive performance starts to diminish from 600ppm upwards.
  • An unhealthy build-up of CO2 commonly occurs in the home – for example, in an inadequately ventilated room filled with family members – and in crowded offices too with an inadequate supply of fresh air. We’ve all experienced the relief when someone opens a window or door because the air has become “stuffy”.
  • In the workplace, elevated levels of CO2 will impair employees’ cognitive performance, having a direct impact on productivity and profitability.

Crowded school classrooms can have real problems with high CO2 levels – directly affecting children’s ability to comprehend and memorise – i.e. severely impairing their learning ability. It is not uncommon for CO2 concentrations in UK classrooms to exceed 2000ppm and some, even higher at over 3,000ppm.

Carbon Monoxide CO

  • Carbon monoxide is a poisonous colourless gas that has no smell or taste.
  • Breathing it in can make you unwell, and it can kill if you’re exposed to high levels.
  • It is present in the atmosphere at extremely low concentrations.
  • It is a primarily a product of incomplete combustion and is extremely flammable and, in certain conditions, explosive.
  • it is typically associated with poorly specified, poorly maintained or poorly ventilated heating systems – gas and oil central heating boilers, water heaters, cookers, ranges, wood stoves, paraffin stoves, open fireplaces etc.
  • It can be produced anywhere where there is a heating system, homes, playgroups, schools, offices and more.
  • It is also a major component of cigarette smoke,
  • When carbon monoxide is inhaled, it enters your bloodstream and mixes with haemoglobin (the part of red blood cells that carry oxygen around your body), to form carboxyhaemoglobin.
  • When this happens, the blood is no longer able to carry oxygen, and this lack of oxygen causes the body’s cells and tissue to fail and die.
  • It is a known foetal developmental hazard, harming the unborn child. It has been associated with: low birth weight or size, learning disabilities, miscarriage.

Ozone O3

  • Ozone is not generally emitted directly into the atmosphere, but is created by chemical reactions between oxides of nitrogen (NOx) and volatile organic compounds (VOCs) in the presence of sunlight.
  • Emissions from industrial facilities and electricity generating stations, motor vehicle exhaust, fuel vapours, and chemical solvents are some of the major sources of NOx and VOCs.
  • Ozone can even be created in a sunny indoor space where there is a presence of VOCs and nitrogen dioxide – for example in an office block next to a busy highway.

Breathing Ozone can:

  • Make it more difficult to breathe deeply and vigorously.
  • Cause shortness of breath, and pain when taking a deep breath.
  • Cause coughing and sore or itchy throat.
  • Inflame and damage the airways.
  • Aggravate lung diseases such as asthma, emphysema, and chronic bronchitis.
  • Increase the frequency of asthma attacks.
  • Make the lungs more susceptible to infection.
  • Continue to long-term damage the lungs even when the symptoms have disappeared.
  • Cause chronic obstructive pulmonary disease (COPD)

Volatile Organic Compounds (VOCs)

  • Volatile organic compounds are a group of chemical compounds some odourless, others pungent, given off (or “off-gassed”) by a number of indoor sources – and can be particularly prevalent in newly made products such as wood laminates, plastic laminates, carpets, carpet tiles, some furnishing fabrics and foam cushioning.
  • Other sources of VOCs include the burning of fuels such as gas, wood and paraffin, as well as tobacco products. VOCs can also be found in products such as perfume, hair spray, cleaning agents, dry cleaning fluid, paints, adhesives, sealants, fillers, lacquers, varnishes, hobby supplies, and from copying and printing machines.
  • VOCs can be released during use or application and even during storage. However, the amount of VOCs off-gassed from products tends to decrease as the product ages.
  • VOCs are instrumental in the generation of Ozone (O3) when, in combination with pollutant oxides of nitrogen in the air, it is exposed to bright sunlight (the Ultraviolet wavelength).
  • VOCs can cause eye, nose and throat irritation, shortness of breath, headaches, fatigue, nausea, dizziness, and skin problems. Higher concentrations may cause irritation of the lungs, as well as long-term damage to the liver, kidney, or central nervous system.

Air Pressure  mBar