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Mark Grayston looks at the role that bolt-on air purification can play in improving IAQ in commercial buildings

There’s recently been a lot of discussion about the role of ventilation in ensuring the air we breathe indoors is safe, and more consideration has been given to indoor air quality (IAQ) than ever.

And, as we see society opening up again over the past few months, this makes perfect sense.

A study from Clean Air Day has found that the level of pollutants inside a building can be more than 3.5 times higher than the outdoor air.

Keeping the indoor air fresh and well circulated is therefore important to help maintain the health and wellbeing of building occupants.

We’re seeing more companies welcoming employees back at least a few days a week, and in some ways we are seeing a return to a ‘normal’ office and everyday working life.

To accommodate this, building managers are looking for ways to ensure they can deliver healthier indoor environments. 

Most spaces with air conditioning can quickly and simply retrofit extra technology to keep customers and employees safe with cleaner, healthier air

Mark Grayston Mark Grayston Head of Product Strategy and Delivery

Improving indoor air quality

IAQ is affected by several factors, starting with the quality of the outdoor air that’s entering the building through ventilation systems, open doors, windows and gaps in the building envelope.

Depending on location, this air can contain any number of pollutants, including NOx and microscopic Particulate Matter (PM) which can be small enough to penetrate deep into the lungs and other parts of the body. 

In addition, there are also potentially dangerous pollutants that can be brought into indoor spaces by the people that enter them - from their sniffles to perfume, or even cleaning products on clothes.

Removing these pollutants is a first vital step to achieving good IAQ, but there are also sources of pollutants already inside commercial buildings.

These include chemicals from carpets and office furniture, or even from cleaning products, along with bacteria, viruses, allergens, such as pollen, dust and mould. 

Mixed with the pollutants from outside, the result is a cocktail of potentially harmful indoor substances in the air. In fact, studies show that the level of pollutants inside buildings can be as much as five times higher than the outdoors.

The need to ventilate

Clearly, this makes a strong case for good ventilation in commercial buildings, and it's well-known that the Covid-19 virus is largely passed through airborne droplets.

Ventilation should always be the first step to consider when improving IAQ, but the challenge of delivering good air quality is complex and has to be balanced with a number of factors other than just ventilation.

For example, the move to improve the airtightness of buildings (for better energy performance) can make achieving good IAQ more difficult.

This means air conditioning has an important role to play too, as the combination of good ventilation design along with the latest air conditioning and filtration technologies can deliver the IAQ required, even in today’s airtight buildings.

In addition, mechanical ventilation with heat recovery (MVHR) is often a good option, as it can simultaneously extract stale air from a building and supply fresh, filtered air. And while doing this, the units will simultaneously recover valuable heat energy for optimum efficiency.

A simple bolt-on device

When it comes to ensuring air conditioning is effective in supporting indoor air quality, it’s not essential to fit an entirely new air con system.

There are solutions available that can be added to existing air conditioning units, designed to be easy to fit onto wall-mounted units, ducted units and ceiling cassette systems.

For example, Mitsubishi Electric’s new Plasma Quad Connect is a bolt-on device that purifies the air and is also highly effective against dust, viruses, mould and allergens such as pollens – it has even been proven to neutralise six key indoor air pollutants and inhibit 99.8% of SARS-CoV-2.

(Derived from and subject to test results, for and on behalf of Mitsubishi Electric, conducted at the Microbial Testing Laboratory, Japan Textile Quality and Technology Centre, Kobe, Japan.)

The sophisticated technology in this bolt-on device can be added to Mitsubishi Electric internal air conditioning units to work like an electrical air curtain to catch and neutralise even microscopic particles in the air – significantly improving indoor air quality.

Commercial spaces like hotels, leisure facilities, medical centres, retail outlets and offices all need to carefully consider how they ensure high indoor air quality.

There are lots of factors to consider, but most spaces that already have air conditioning in place can quickly and simply retrofit them with the extra technology to keep customers and employees safe with cleaner, healthier air.

Mark Grayston is Head of Product Strategy and Delivery