The problem of pollution: indoor v outdoor air guide

As specialists in oil mist removal, Filtermist is only too aware that there’s a global problem with the air we breathe. Headlines such as ‘Air pollution in China is killing 4,000 people every day’ and ‘Unchecked air pollution a death sentence for millions’ scream out at us from the front pages of newspapers and online news sites from around the world.

While most of us may not be able to physically see a smog over our towns and cities anymore as our ancestors did, we certainly shouldn’t be fooled into thinking this means the air is clear. And we definitely shouldn’t believe staying indoors will solve the problem.

What is the problem?

Over the next 30 years, it is expected poor air quality will be the leading cause of premature deaths worldwide.  A third of deaths from strokes, lung cancer and chronic respiratory disease, and a quarter of coronary heart disease deaths are attributable to air pollution, according to the World Health Organisation.

There are natural causes which contribute to the pollution we experience, but the majority are man-made, coming from the great sprawling towns and cities we have built, the cars and lorries we drive and the factories we work in.

Work is already well underway to reduce the amount of pollution in the air we breathe, with world leaders attending conventions, Governments setting targets, and sanctions being put in place. But it seems the world is obsessed with the quality of the air outside, while barely even considering what’s going on inside.

A focus on outdoors
There are multiple laws, policies and regulations which govern every aspect of outdoor life – from the emissions released from factories, to the cars we drive. The UK, for example, is signed up to the Gothenburg Protocol, set out by the UNECE Air Pollution Convention, with strict emission ceilings for sulphur, nitrogen oxides, volatile organic compounds (VOCs) and ammonia. As part of this, the Government must send annual reports, stick to tight limit values for specific emission sources such as cars and electricity production, and provide predictions for future years.

In the UK, the Clean Air Act has been in place since 1956 with various amendments and a National Air Quality Strategy further governs what can and can’t be done. The latest UK development is the launch of a new Clean Air Strategy which is currently under consultation. Where local authorities are not meeting the national objectives, they must declare an Air Quality Management Area and produce an action plan. Many councils have introduced park and rides, better cycle routes and encouraged car share schemes and use of public transport in a bid to reach the goals set out by Government.

How many hours do we spend indoors?
There are no end of rules and regulations when it comes to the quality of the air outside – and rightly so – but it’s estimated those living in developed countries spend approximately 90 per cent of their time indoors.

In fact, one survey which asked 1,000 adults in Britain about their habits on weekdays revealed the average respondent spent 92 per cent of their time indoors. This means just 115 minutes (less than two hours) is spent outside every day with 1,325 minutes spent indoors in a 24-hour period.

So why does Google return 73.7million results for ‘outdoor air pollution’ while a search for ‘indoor air pollution’ returns just short of 8.6million?

While this is a fairly basic and light-hearted way to show where the focus lies when it comes to pollution, it is clear that the world’s attention is very much on the quality of the air outside while the effect our homes and workplaces may be having on our health is largely under-reported.

What about indoors?
There is currently no Government department responsible for the indoor air we breathe. There are a number of different pollutants which affect indoor air quality, from the use of chemicals and smoking, to outside pollutants migrating inside and natural radon gas.

In a Government PostNote published in 2010, it was stated: “In general, the issue of indoor air pollution has been largely overshadowed by the attention focused on air pollution outdoors related to industrial and transport emissions…There is a need for more information about levels of exposure to indoor air pollutants, as well as the risks posed by long-term exposure and from new developments such as nanomaterials.”

In China which has four cities exceeding World Health Organisation air quality guidelines, sometimes with visible smog above them, some are waking up to the idea of the need to focus on indoor air. The newly-opened Cordis Hotel in Shanghai boasts in-room pollution monitors (with PM2.5 levels displayed on every television screen) and claims the air is up to ten times cleaner than the air outside.

Work-related pollution: oil mist
Despite the wealth of regulations governing outdoor air pollution worldwide, there are still some countries such as Germany and China (with the exception of Shanghai) which do not have formal guidelines in place to protect employees against exposure to oil mist and other harmful airborne contaminants.

Even in the UK, the realisation about the damage being done to workers’ health by potentially being exposed to hazardous airborne substances has only been a concern for around the last 30 years. In 1988, the Control of Substances Hazardous to Health (CoSHH) guidelines which were introduced by the Health and Safety Executive (HSE) set down rules which must be followed by every employer.

In the same year, a report entitled Occupational Asthma due to Oil Mists was published by Doctors Robertson, Weir and Burge from the Occupational Lung Disease Unit at what was then known as East Birmingham Hospital.

The HSE then published its HSG258 Controlling Airborne Contaminants at Work guidelines in 2008.
There are employees from other countries who are not afforded the same level of protection when it comes to their health. Thankfully, there are some employers choosing to invest in effective oil mist removal even where there is no legal obligation to install air extraction and filtration systems.

This is partially due to the fact those joining the workforce are waking up to the idea they can demand to work in a clean environment - even in careers traditionally thought of as ‘dirty’ such as manufacturing. In Germany in particular, the unemployment rate is so low job-seekers have somewhat of an advantage when it comes to selecting where to work and companies are looking for ways to attract the most skilled workers. Being able to guarantee their health will not suffer because of a poor working environment is a huge advantage here.

Workers are still suffering
Despite the introduction of guidelines having a positive effect on air pollution over the past three decades, the problem has not been entirely resolved. A report published in 2014 by the HSE (Work-Related Respiratory Disease in Great Britain) estimated 33,000 people who worked over the previous 12 months currently had breathing or lung problems caused, or made worse, by work.

The report estimated 141,000 people who had ever worked currently had breathing or lung problems at least partially attributable to work, with ten per cent of those cases related to airborne materials while welding, soldering or cutting and grinding metals.

Although the problem has reduced, there are still examples of workers being exposed to contaminated air in the UK where the guidelines exist. Employers must continue to be educated about the dangers and how to eradicate the risk in order to stop more workers being left with long-term health problems as a result of their working conditions.

Air Quality Index
The quality of outdoor air is measured using the concentration of particles PM10 and PM2.5. The larger particles (PM10) are around the same size as flour and are visible, they will be stopped in the nose and mouth of the person breathing them in. PM2.5 particles, including oil mist, are the same size as bacteria and will be caught in the throat.

In some cases, the threshold inside a factory is ten times higher than the value considered hazardous in the street.

Typically, cities with low pollution will have 0.015mg/m3 particles while a city would be considered polluted with 0.3 mg/m3 and schools in Beijing have closed due to heavy pollution at 0.5 mg/m3. In contrast, the threshold for allowed oil mist levels in many European factories is 5 mg/m3. While outdoor air pollution particles and oil mist particles are not the same, they are the same size and thus able to reach the same point inside the human body.

Say the word pollution and it immediately conjures up visions of smog, car fumes or smoke from a factory chimney. But pollution is everywhere – in the homes we live in, and in the businesses we own or work for. The world is slowly waking up to the need for clean air whether a person is inside or outside – but the shift of focus from outdoors to everywhere has been a slow one and much work is still needed to educate people about the need for clean air and the contaminants which threaten their health.

Established in 1969 in Shropshire, UK, Filtermist is a leading manufacturer and marketer of oil mist collection units and fume and dust extraction equipment, for all types of manufacturing and engineering processes. The company offers local support in more than 60 countries worldwide through a network of carefully selected distributors.

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