Another indoor air quality conundrum

Yesterday, the UK government announced that all remaining restrictions relating to Covid-19 are to be relaxed on July 19th. There will no longer be a requirement to work from home when possible (something that seems to have been gradually ignored by many organizations for weeks already) and schools can abandon bubbles and even mask wearing and social distancing.

To mitigate some of the effects of increasing infections and the removal of passive measures such as masks and distancing, better ventilation of buildings is encouraged.

One way to measure ventilation is by using a proxy measure of carbon dioxide concentration, and that is pretty easily achieved with IAQ monitors. Carbon dioxide concentration is a good proxy measurement for ventilation as the higher the levels of CO2, the fewer air changes are taking place. If CO2 levels are high, then increasing ventilation is a good option. Not only will it have an impact on virus transmission, but it will also improve cognitive ability and reduce the risk of drowsiness. High levels of CO2 are very much associated with poor productivity.

Awair Omni OAQ monitor

The easiest way to improve ventilation is to open some doors and windows. In most schools, that is the only way to do it – very few schools have complex HVAC systems that can adjust ventilation rates and still pass air through filters.

If you have an IAQ monitor that measures a range of parameters, such as particulates and VOCs as well as CO2, then as soon as you open a window, you might discover that other pollutants increase rapidly – and then what are you going to do? Balancing the health risks of the different contributors to poor IAQ is hard enough already, without the added complications of a nasty virus

Many schools, especially those in urban areas, as well as office buildings, are situated near busy roads and particulate pollution especially is known to be very damaging to respiratory health. Measurements of particulates near roads are sometimes way above safe limits and high concentrations of fine particulates can kill or seriously damage health.

Photo by thevibrantmachine on

So, here is the puzzle that has to be solved. Will opening windows to reduce the risk of ill health due to airborne viruses (such as Covid-19) cause a bigger impact on health by letting in a whole load of other pollutants, especially fine particulates?

There are, of course, some things that can be done to reduce the amount of particulates getting into buildings.

The first is to reduce them at source. In urban areas, the main source is traffic, especially traffic using internal combustion engines. The rapid increase in electric vehicles is certainly going to help, but it will take many years before they are off the roads completely, and the most polluting types of vehicle are the hardest, at the moment, to electrify (big goods vehicles).

Next, you can try and reduce the chances of those particulates getting inside a building with open windows. This is not going to be easy, but there are some effective measures, and they are mostly green.

Green walls, green screens, climbing and scrambling vegetation, trees and hedges are all capable of trapping large quantities of particulates on their foliage, and have an impact on urban heat islands too.

A Mobilane Ivy screen trapping particulates and keeping the noise down

Trees, hedges and plants like ivy are actually quite cheap too, and they are self repairing. They also reduce noise and look good too.

In the short term, using ventilation to flush out viruses (along with excess CO2) is going to be better than leaving windows closed and minimizing the ingress of fine particulates, but that is not a viable long term solution. Ideally, we should always have good ventilation to flush out viruses (it would be a good idea to use ventilation against all respiratory viruses, not just Covid-19), but if that is the case, we must do more to prevent other pollutants getting inside buildings. Vegetation is going to help a lot, but removing the source of those pollutants has to be the ultimate goal.

An indoor air quality conundrum

Something smells good

I have seen a notable increase in the number of posts on platforms such as LinkedIn extolling the benefits of ambient scenting – the addition of a high quality fragrance to the air inside buildings to make them more appealing (this is not the same as the use of air fresheners, no matter how sophisticated, to mask malodours in settings such as washrooms).

This is actually a subject I know quite a lot about (I’ve had a bit of a love/hate relationship with the subject since about 2007), and I can certainly vouch for the effects that scenting has on mood and the perception of the qualities of a space.

Ambient scenting can be used to reinforce brand values, make a place appear more luxurious and has even been shown in some experiments to reduce anxiety in healthcare settings. Some smells are very good at increasing the perception of good air quality – think of those fragrances that smell especially clean, fresh and hygienic.

Ambient scenting also has a role to play in biophilic design – potentially a very big role. Our sense of smell is our most primitive and we often react to a smell before we are consciously aware of it. Scents redolent of nature, when combined with appropriate visual and textural stimuli certainly add an extra dimension to a space – when our senses are stimulated congruently, our surroundings make more sense to us.

The technology of scenting is highly sophisticated (far more complex than an aerosol can or a scented candle) and is often programmable and even web-connected. Furthermore, the actual amount of fragrance chemicals released into the environment is actually really tiny – just enough to be perceived (this is especially true of nebulising systems). Some systems are designed to scent whole buildings through the HVAC infrastructure, with the fragrance oils introduced directly into the air handling unit.

Cleaner air

As well as spotting the increase in the number of posts about the benefits of scenting, I have also seen an increase in posts about air purifiers. This is clearly a hot topic. Even before the Covid-19 pandemic, poor air quality was high on the agendas of public health officials and building managers. Poor indoor air quality is associated with symptoms related to sick building syndrome and can, at times, pose a risk to the health of building occupants.

The development of new building standards, such as RESET, and the incorporation of IAQ monitoring standards into schemes such as WELL has brought not only management of IAQ, but also the monitoring and reporting of IAQ to the fore.

This is a good thing, and a subject that I have touched upon before. New research has shown that an increasing number of people are expecting more transparent reporting of IAQ in offices, especially amongst those facing a return to regular office work as pandemic restrictions ease.

Air purifiers are interesting products as well. Different systems employ a variety of technologies to remove fine particulates and remove, or breakdown, volatile organic compounds (VOCs).

Unfortunately, as far as I know, none of these air purifiers is able to distinguish between harmful, or unwanted, VOCs and those that smell nice and which were put in the environment deliberately.

The conundrum

The issue that is puzzling me is that many of the companies promoting ambient scenting are also promoting air purifiers, and this strikes me as strange. What drives this corporate cognitive dissonance?

If a company is selling an air purification system, one would hope that their sales people are able to present the features and benefits with some degree of conviction and be able to explain how an air purifier works and what it does to the chemicals circulating in the air.

Likewise, a sales person selling a scenting service should be able to explain how adding more chemicals to the environment can improve the users’ experience of a building (a scenting machine is a product that is designed to actively put more chemicals – no matter how safe they might be – into the environment). I’m not trying to be confrontational here – buildings that smell nice can certainly make using that space more enjoyable. People use fragrances all the time in homes and, of course, on their bodies.

It is quite possible that in situations like these it is likely that the left hand is unaware of what the right hand is doing. The people selling air purifiers may not be the same people that are selling ambient scenting (even if they work for the same company).

Furthermore, the purchaser of the scenting system might not be the same person as the purchaser of an air purifier (even if they work the same customer). If it is the same purchaser, that person now has the burden of potentially making an uninformed choice: is it reasonable to expect a customer to know that the air purifier will eliminate, or at least reduce, the efficacy of their expensive ambient scenting system?

One mitigating argument is that scenting systems are supposed to be situated where air purifiers aren’t. If that principle was universally applied, then there might be no issue – and maybe that is the norm. But I am not convinced that is always the case, especially with an increase in sales of portable air purifiers. These, by their nature, are going to be moved around and quite possibly moved into spaces where there is a scenting system in place. It is also possible that the person specifying the air purifier is unaware of the the presence of the scenting system.


I think it is unlikely that companies are deliberately selling both services to be used in the same spaces. There might be a short-term gain by doing so – the customer is going to get through a lot more expensive fragrance than might otherwise have been the case – but I doubt it would take very long for them to spot the problem.

Being a benevolent sort of person, I suspect that the poor sales people flogging air purifiers and scenting systems might not be sufficiently aware of the other products and services offered by different parts of their company (although their marketing departments ought to be). And if they are unaware, it makes it harder for them to help their customers make informed choices. This is clearly an opportunity for some training to be given (and if you are one of those companies facing this dilemma and would like some training developed for your sales and/or marketing people on this matter – please get in touch and I might be able to help you).

If sales people are actually selling both types of product, especially to a purchaser that might be responsible for buying both types of product, then there is an even greater need for some education to ensure that they remain credible and really understand the needs of the customer.

Biophilic design in the new workplace

I had the great pleasure of being interviewed by Dr Vanessa Champion, editor of the Journal of Biophilic Design last week. We discussed biophilic design in the new workplace and also biophilic design in the home working environment (which is, for many, going to be the workplace for a significant portion of the working week).

Personalisation of space is a key message in this podcast. There are tips on how Biophilic Design supports and benefits the whole person and how it enhances a whole sensory environment. Some designers might separate off those elements from Biophilic Design, but they are all an integral part, including views, improved acoustics, lighting, ergonomics and when used together provides us with an holistic solution. It’s all about comfort.

As a horticulturalist, I also discuss the benefits of plants, and we also talk about new styles of workplace and ways of working. People are talking about new hybrid ways of working, where some are working from home, some are in the office, and some half and half. Creating collaborative spaces, being able to break up big expanses of open plan offices with planting is an excellent idea. It also will give the feeling of comfort, improved acoustics, privacy.

Biophilic design and animal products

Recently, someone asked me whether I thought leather had a place in biophilic designs. It’s an interesting question, which I answered with a few off the cuff ideas, with the promise to think about it in more detail.

My initial response to the question is “it depends”. As someone that eats animals, and has no religious belief, I have no ethical problem with using animal skins and animal fibres, as long as it is not gratuitous or involves endangered wild species. I wear leather shoes, and have, in the past had leather sofas and leather upholstery in a car.

Everyone’s ethics have their boundaries, though, and there may be no logical reason for those limits. For example, I’m not a fan of fur farming (but what is the real moral difference between eating and wearing an animal?), and I am certainly very interested in seeing how lab-grown meat develops.

As mentioned above, I have no religious beliefs, but many do. The ethics of the religious are guided by the teachings of their religion, and there may be taboos about which animals may, or may not, be exploited for food, fibre or hides.

It could be argued that leather is a good use of a waste product. If we, as a society, are content with farming animals, then surely it is right that we use as much of that animal as possible. That might make leather a useful (and arguably a more sustainable) product, but not necessarily biophilic.

Moving back to the main question: does leather have a place in biophilic designs, assuming no ethical objection? From my own, possibly narrow, perspective, I’m not sure that leather is, per se, a biophilic material, even if it is a natural(ish) product. It is highly processed – rarely resembling an animal skin by the time it is tanned, coloured, stretched and made into a product.

For me, biophilic design is first and foremost about comfort – physical and psychological. We are most comfortable when we are in environments that stimulate our senses in a way that reflects our evolutionary history as plains-dwelling animals, using well-adapted and highly evolved senses to find food, fuel, water and shelter. This is something I have covered in previous posts, so won’t go into great depth here.

This might be a biophilic space, but does the sofa have to be leather to make it so?
Photo by Ksenia Chernaya on

In artificial environments, like cities, we can recreate concordant sensory stimuli through design, and that might (and often does) mean the use of artificial materials. In fact, in urban environments, it is only possible to create biophilic environments by using a wide range of synthetic materials and manufactured products.

Floor coverings are an excellent example of where synthetic products can be used in a biophilic design (good examples from Interface, who are pioneers in biophilic design and sustainability), and wall coverings too. Consider also lighting and acoustics. Modern biodynamic lighting and AI-generated soundscapes that recreate natural stimuli are only possible with advanced technology.

One final point. Good designers make sure that they are aware of the users of the environments they design. In commercial spaces, it is likely that vegans, or followers of some religions, will find the use of some animal skins or animal fibres offensive or taboo. In that case, why risk unnecessary hurt when there are alternative materials available.

So, in conclusion – I think that it is possible to create fantastic biophilic spaces without using leather or other animal products. On the other hand, if a designer (and all the users of the space that designer is creating) have no ethical issues with using animal products in design, then they can be used as part of a biophilic design.

Post pandemic plantscaping. Part 2

What’s next for the interior landscaper?

The interior landscaping industry is having to adapt very quickly to changing market conditions, and it has been fascinating to watch how that is happening.

After the initial shocks of Lockdown 1, followed by the gradual reopening of offices and hospitality over the summer, many in the industry looked to adapting conventional ways of doing business to adapt to the physical changes in the workplace. A lot of effort was put into using vegetation to enable or encourage physical distancing – screens, barrier planters, plants used to enforce pedestrian traffic flow around a building, etc. These all had some short-term impact and kept many interior landscapers busy (and in business).

Clean Team Florence sanitizer planter from Livingreen Design

Others looked to diversify their offering. Innovative planter manufacturer, Livingreen Design, developed a range of planters that incorporate a hand sanitizer dispenser, which, along with other hygiene and disinfection services has allowed some plant companies to offer additional valuable services to their clients – although keeping plants extra clean is also a challenge.

It’s going to be relatively easy to wipe down desks and screens once or twice a day with a disinfectant wipe, but we don’t know how well, or for how long, viruses can survive on the surfaces of leaves, flowers or moss. We also don’t know the effects of using surface disinfectants or fogging on plants: many plants are not going to thrive with a daily dose of Dettol spray. With those considerations, it may be that companies decide that plants in offices are going to be too much trouble.

Great for desks and hard surfaces, but what about plants?

Lockdowns 2, 3 and beyond: What can plantscapers do?

Hoping that everything is going to return to the way they were, and planning on carrying on as before, is probably not going to work. The landscape of the workplace (as well as hospitality and retail) is going to be very different – for months, if not years to come. How can the interior landscaping industry adapt?

Doing nothing and hoping for a return to the pre-Covid ways of doing things is likely to lead to bankruptcy. Even with the promise of a vaccine being realised, too many businesses have noticed the benefits of home working and other hybrid set ups. Office costs will be lower, and office buildings will be reimagined. Employees will see many benefits from more home working (time and money saved on commuting, being one advantage) and the towns and suburbs might be revitalized as city centre business districts get quieter.

That means conventional interior landscaping will be less appropriate than it was before. Offices that do remain are likely to resemble co-working spaces and have more in common with hospitality venues than conventional open-plan offices.

Indeed, the trend to such design styles was made evident recently when Plants At Work, the UK trade association for the interior landscaping industry, held its annual awards ceremony. Case studies of some award winners, e.g. SLG Cheltenham, Farfetch or Uncommon, Liverpool Street really show how such a design style is becoming more common.

These new ways of designing interior landscapes may present some challenges. Individual spaces in buildings may be used irregularly, which may mean inconsistent lighting and heating, which may affect the choice of plants used, or their maintenance schedules.

Other interior landscapers are looking towards putting their expertise in designing plant displays, using high quality plants and planters, to use to supply the growing number of houseplant enthusiasts as well as homeworkers missing their office greenery (good examples are In-tray Plants from Indoor Garden Design, or Foli8 from Planteria).

Technology and flexibility

Adapting to customers moving away from their traditional locations in city centres brings a number of logistical challenges. With customer density changing, service operations have to become more efficient. This is where technology offers some interesting opportunities.

Nurtio Technologies has developed an innovative system that combines a sensor (that measures soil moisture, temperature, light and nutrient levels) and a clever artificial intelligence algorithm that can help plan service schedules and alert the interior landscaper if there are sudden changes to the environment.

By learning the behaviours of individual plants (and groups of plants at the same location), the algorithm can predict when, and how much, water should be added and enable some flexibility in service schedules. One interesting opportunity that might arise, especially if access to buildings is tricky, or if plant displays are more dispersed as a result of a move to remote working, is that the business of watering plants can be delegated, leaving more time, or capacity, for skilled horticultural technicians to do the more complex parts of the job: pruning, grooming, pest/disease management and carrying out changes and re-designs.

UK interior landscapers needing more information about the benefits of the Nurtio system should get in touch with me.

One of my happy places

I recently started a contract for a couple of days a week with a UK interior landscaper to help with the launch of a new line of business. Most of my work is carried out from home, at my less than perfect home office set up (OK, it’s the dining table), but last week I needed to visit their premises.

It has been a while since I was last in an interior landscaper’s premises. Despite each company’s differences in set up and size, there is something quite special about walking into the plant storage and preparation area. All the plants stored and being prepared for new installations. Everything labelled and assigned to each plant technician for their weekly routes and racks of containers and sundries ready to be assembled into displays that bring life to commercial spaces.

There is also the atmosphere. There is no doubt that a space with thousands of healthy plants has a special feeling. There is the smell of compost and freshly-watered foliage. It is quiet – even when people are working, there is a sense of calm, and there is a sea of green. I have written before about the human eye’s ability to discern hundreds of different shades of green, and in locations like this, you will certainly many of them.

I spend most of my working life at a desk: writing about workspaces, writing about interior landscaping, joining video calls and meetings (that was my work pattern for years, even before the pandemic), so this trip out was a welcome chance to refocus.

When did you last hear birdsong?

Today is the 22nd of December, 2020. Here, in tier 4 Kent, it is quiet. Schools have broken up for the Christmas holidays and, thanks to a new strain of the Covid-19 virus, we are experiencing a near lockdown. This means the roads, and the skies, are nearly empty.

Oddly, it is also 14 degrees Celsius, the rain has stopped (for a while at any rate), and it is warm enough to sit in the garden with a cup of coffee and contemplate life. As I sat, looking at the garden (and thinking about the jobs that need to be done there, as well as those indoor chores, and for work), I tuned into the sounds. A robin was singing, pigeons and doves were making there less tuneful noises, and sparrows were chirping.

Photo by Pixabay on

Around here, we also have small flocks of parakeets, which add an exotic touch to the area. Whilst they don’t have a pretty song, they do look stunning as they flash by.

That fifteen minute break cleared the mind in a way that a fifteen minute break on the sofa, or at the desk, couldn’t do. It allowed my eyes to focus on distant object (trying to find the tuneful robin in a holly tree), my sense of smell was treated to fresh coffee (which somehow smells better outside) mingled with the evergreen mossy smells of a damp garden and my ears tuned in to that bird. The sensory stimulation was congruent – there were no clashes.

A recent paper in Frontiers in Psychology (Minimum Time Dose in Nature to Positively Impact the Mental Health of College-Aged Students, and How to Measure It: A Scoping Review) investigated the research that has been carried out into how much time in nature is needed to positively impact the mental health of college-aged students.

It turns out that it isn’t very much. The authors sifted through over a thousand papers and carried out a detailed review of 14. The key finding of the review was:

These studies show that, when contrasted with equal durations spent in urbanized settings, as little as 10 min of sitting or walking in a diverse array of natural settings significantly and positively impacted defined psychological and physiological markers of mental well-being for college-aged individuals.

Making yourself aware

One of the questions in the WorkFree assessment tool asks “When did you last hear birdsong?” It is not a trick question, it is there to make you think consciously about the last time you were aware of the sounds of nature. It is there to remind you to take as break from your desk once in a while and go outside and just be in the moment. Tune in to your surroundings and let your senses be stimulated from every direction.

This is even more important in the winter. It is too tempting to just stay indoors. For home workers, it could mean that you don’t even get a daily walk from your front door to the car or station (which office-based workers have to do, regardless of the weather), and that means your world shrinks to a few square metres.

Being in nature does not necessarily mean being in the countryside

The study mentioned above refers to how much time in nature is needed to benefit mental health. The studies excluded long excursions into deep wilderness (which is just as well, given the scarcity of real wilderness in Southeast England) and concentrated on easily accessible nature. That means public parks and gardens as well as walks in the countryside, and almost everyone in the UK is within a few minutes walk of a public open green space, whether it is a pocket park, canal towpath or some woodland.

The benefits of being in nature, for even a brief period, are now well understood.

“The future belongs to the nature-smart – those individuals, families, businesses and political leaders who develop a deeper understanding of the transformative power of the natural world and who balance the virtual with the real. The more high-tech we become, the more nature we need”
Richard Louv

Richard Louv, in his book The Nature Principle, explains it really well. The whole book is very readable and I highly recommend it, but the chapters in the section called “Creating Everyday Eden” are especially relevant to the world of work, especially chapter 15, Nature Neurons go to Work. The book was written just as the benefits of biophilic workplace design were becoming understood – references to office design and indoor greenery abound, but the message is just as relevant now in times of home-based and hybrid working.

Making life easier for interior landscapers in 2021 with sensors and data

Pre-production samples of Nurtio Technologies sensors have arrived for testing. Three different soil probe lengths and a sensor for hydro plants – all fit into a common power unit that connects to a gateway, and which also houses the light and air temperature sensors.

Everything fits together really well and is a breeze to install – here into a 12 yr old semi-hydro Schefflera arboricola. Data being fed back to Nurtio and will be displayed on a dashboard and app.

This is a really well designed system and will bring great benefits to interior landscapers for service planning, training, assurance and customer care. These are ideal for high value displays, such as expensive indoor trees or green walls when you need to know quickly when the environment changes. The system is also have great value for standard container plants too – it will learn about the needs of the plants and help plan service schedules.

If you are an interior landscaper and would like to know more about this system, please get in touch – this could make your service operations in 2021 much more efficient, especially if your plants are more spread out than before in the new world of dispersed workplaces.

More information at

The biophilic home office

Image by Simply-C-Photography for Fusion Spaces

Biophilic design need not be confined to office buildings and other commercial spaces. The benefits of biophilic design can be obtained in the home office too, and without having to spend a fortune. My recent post for Fusion Spaces explores the benefits of biophilic design and gives some very simple and cost-effective tips to help you thrive in your home working setting – it’s not just about plants (although, of course, they are very important), it is about all of your senses.

Why biophilic design is NOT about bringing nature indoors

It might be a tempting shorthand, but too many interior designers and interior landscapers talk about biophilic design in terms of bringing nature indoors. This is simply not true. The last thing you should be doing is to bring nature indoors – at the moment it is wet, windy, cold, muddy and the trees are shedding leaves by the ton. I don’t want foxes and crows gallivanting on my desk or slugs climbing my walls. If I want to be surrounded by nature – which I often do – I go for a walk in the fields or woods nearby.

Biophilic design is about improving wellbeing by using some of the cues of nature. As animals, we are as prone to being stressed in unnatural environments as any other species, which is why enclosures in zoos are designed to be as close to the animal’s natural surroundings as possible (and safe).

As a species, we have spent less than a 1% of our history as a domesticated animal (Professor Alice Roberts’ book, ‘Tamed, explains rather brilliantly why humans are the ultimate domesticated species – we domesticated ourselves). With that in mind, we need to create our enclosures to be as stimulating and stress free as possible.

We can do that by recreating natural stimuli in buildings – physical and mental – and that does include bringing some natural, or naturalistic elements into our buildings, but it doesn’t mean bringing nature indoors, because that is a bit messy.

For any advice on biophilic design, or if you are working on a project where biophilic design is an important element (and perhaps you are thinking only of plants), please get in touch.