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Fascinating study on how lighting, acoustics and CO2 levels affect learning

March 3, 2020, 8:17 GMT+1
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  • Professor Stephen Heppell launches a fascinating study on how lighting, acoustics and CO2 levels affect learning...
Fascinating study on how lighting, acoustics and CO2 levels affect learning

What has a dramatic affect on learning and behaviour? Is it teachers? The curriculum? Interesting and engaging lessons? Or is it environment?

It may come as a surprise to some that the conditions in the classroom can have a huge impact on children’s ability to learn.

I was a schoolteacher for more than a decade, and have been a professor since 1989, working with schools and governments around the world to improve learning spaces.

Myself and my colleagues recently met with Essex County Council, explained to them the link between CO2 levels, lighting and acoustics on learning, and we were subsequently invited into Fingringhoe Primary School, in Essex, to test our theories.

We did that with the aid of a compact device we’ve developed called the Learnometer, which contains a series of internet-connected ambient sensors and onboard software to help us measure and analyse environmental data.

Our hope is learners, and therefore schools, can ultimately perform better by optimising the physical environments they use for learning.

Research carried out by ourselves and others confirms that poor light levels, variable temperatures, inappropriate sound volumes, humidity, excessive amounts of CO2, and air pressure can all impair learning.

The Learnometer is able to automatically sample a classroom environment and make suggestions via a unique algorithm as to what could be changed so that students to learn and perform at their best.

The focus throughout our research has been on the aggregation of marginal gains. Take light, for instance. In a classroom, you need good light for your brain to work well.

Outdoor light often measures up to many thousands of lux; indoors, 1,000 lux would be a good taget, but 500 will do.

Below that, however, learners’ attention, level of engagement, powers of recall and more will start to decline. Their behaviour and performance will become noticeably worse.

We therefore took one classroom at the school, assigned it to a class and talked to the children about what we were doing.

The pupils were surprised to be shown how children sat in a dark corner of the room were those at risk of losing concentration, while their peers in a lighter area by the window were still sharp by the end of the day. They’d previously thought that this was purely down to them personally.

Over the 2019 summer holidays, in collaboration with Essex County Council’s key suppliers, we gave the room a makeover. An old floating ceiling was pulled down, the room was repainted, acoustic panels were installed and tiered seating and writable surfaces were put in.

We carried out acoustic modelling to examine the impact of bass resonance on the kids, particularly those struggling with attention issues.

The room itself is a Victorian classroom, with a lovely high vaulted ceiling that turned out to have skylights. It’s a great room which seems to have been spoiled over time by years of modification.

We’ll now await the results of these changes, and see what improvements to the children’s learning and behaviour they might make.

Professor Stephen Heppell is Felipe Segovia Chair in Learning Innovation at Universidad Camilo José Cela, Madrid


An acoustically demanding environment

Schools are the most important and acoustically demanding environments that we design. The vast majority of teaching still depends on verbal communication in surprisingly difficult conditions.

If we design a meeting room or lecture theatre for 30 adults it will have very carefully controlled acoustics, low background noise and probably a speech reinforcement system, but we still expect teachers to manage merely by raising their voices in often noisy rooms with the legal minimum of acoustic treatment.

We know that better acoustic conditions improve children’s understanding, concentration and ultimately academic results and reduce stress for pupils and teachers alike.

We also know that children with hearing impairments and other special communication needs, including ASD and ADHD, must be taught in rooms with shorter reverberation times, lower noise levels and smaller class sizes.

That is acknowledged in the DfE’s own standards and guidance, yet we persist in putting them into large, noisy, mainstream classrooms with the cheapest possible acoustic treatment.

Essex County Council is one of the few authorities which have recognised and addressed this problem by designing all new classrooms to a better acoustic standard, and I sincerely hope that their work, supported by Ecophon’s research, encourages other education authorities to start providing the acoustic conditions that pupils and teachers deserve.

Adrian James, Director Adrian James Acoustics


Bring your own plant

Countless studies confirm that the right plants can have an active role in reducing CO2 and increasing oxygen particularly in any closed space.

We have been encouraging schools to harness the power of plants through Bring Your Own Plant projects, which really do make things better during the school day. Better oxygen brings behaviour, engagement, wellbeing and other gains.

Firstly – which plants? Helpfully NASA has published their own research because colonising Mars et al will need some plants that do a great job making oxygen from exhaled CO2.

James Clarke at learniture.co.uk then made some of that list congruent with a list of plants that do not cause irritation or worse in contact with children, and that gives a definitive list of these few ideal plants (super sensitive kids, leave out 3 and 4):

  • 1: Dwarf Areca palm – (Dypsis lutescens)
  • 2: Boston Fern (Nephrolepis exaltata)
  • 3: Devil’s Ivy (Epipremnum aureum)
  • 4: Chinese Evergreen (Aglaonema commutatum)
  • 5: Spider Plant (Chlorophytum comosum)
  • 6: Aloe Vera

Secondly, having given this list to the children, they buy and bring into school “their” plant, which they should name affectionately. Naming seems to make this a very popular activity but keeps the plants, their welfare and their impact foremost in the students’ minds.

They often greet their plants in the morning for example and observe / monitor their moisture levels etc. Ideally, the plant needs to be in a white pot – normally the school provides these for uniformity and to make sure they fit the plant-pot holders.

Photosynthesis uses light absorption, white pots reflect light a little more to help balance this.

Thirdly, measuring the CO2 at perhaps three points during the day, before and after the plants were added will surprise you. It provides a good data visualisation and graphing task too, of course.

Target CO2 is to keep below 1,000 parts per million (ppm) throughout the day, and you will all notice when levels are worse (above) than that.

Professor Stephen Heppell


A massive makeover

In our Year 6 classroom, carbon dioxide levels were high, lighting was poor, the false ceiling was brown and ladybird infested. Even the best lessons had pupils yawning!

We were nervous about pulling down the brown, false, hessian ceiling to see what lay above, so, after checking things weren’t too serious with a selfie stick and phone camera, we pulled down a small section.

Fortunately, we weren’t the ones standing underneath when it was pulled down… Years’ worth of dust and insect skeletons rained down. The false ceiling and roof trusses were dismantled, along with anything else that appeared unnecessary.

Disused, trailing cabling and trunking were removed. Next, the classroom was painted a bright white, from top to bottom, to reflect light around the space. Followed by lighting and acoustics.

Key Factors that we have changed included:

  • air quality (oxygen/CO2 levels)
  • temperature
  • light and brightness (colour of walls and ceiling can affect this)
  • sound/acoustics
  • Heppell benches
  • writing walls

The room has also been fitted with a folding writable wall, and the Heppell tiered benches. There is even a special wall of plants – each one owned by individual pupils — to increase oxygen levels.

The change from tables to tiered benches has enabled teachers to think more creatively in how they allow pupils to make appropriate choices about how they complete learning tasks.

Suzy Ryan, headteacher at Fingringhoe Primary School


A collaborative approach

Delivering projects collaboratively, through frameworks has many advantages, not least the ability to bring together all stakeholders on a frequent basis to share knowledge, learn from others and improve outcomes.

At one of those Best Practice sessions, Professor Stephen Heppell explained how small incremental changes can make such a difference to a classroom environment. By the end of his excellent and animated presentation, we had 70 people in the room extremely keen to make learning better!

So Fingringhoe Primary School was approached, and with the amazing support from their headteacher, staff and children, a brief was developed with Stephen and the pupils.

It concluded the need to improve the lighting, acoustics, CO2 levels, replace some furniture, introduce write on surfaces and make some decorative changes.

The aims of the project are to build a grounded set of improvements that are cost effective, attainable and proven which can be promoted and emulated by other schools, inform other work in our estate, help build reflective practice amongst colleagues and children, promote physical activity and make learning better today.

While this study is still at its early stages, the classroom teacher has already stated to me that she would not wish to revert to her previous classroom and, best of all, some children have written to me about their classroom to say “the white walls have helped us because they make us more awake” “the ceiling being replaced has stopped the echos”, “we can concentrate as the noise levels have changed” and “It wakes us up and makes us want to learn”.

A report will be produced by Stephen Heppell after the end of the academic year.

Greg Keeling, Engineering & Technical Team Manager, Essex County Council


Five fundamental factors

There are five fundamental factors for an optimal learning environment: natural and artificial lighting, acoustics, air temperature, air quality and ergonomics.

Stephen Heppell’s vision for Fingringhoe meant opening up the classroom by removing the outdated false ceiling and letting the light back in. The result: a much improved lighter and airier space, but with a very high ceiling and increased acoustic challenge.

Bigger volumes, especially with hard surfaces, result in longer reverberation times (more echo) and therefore, poor speech intelligibility.

Independently tested by Adrian James Acoustics, the new space at 1.2 seconds fell well outside design standards, BB93: Acoustic design of schools.

Several notable research projects, not least the respected “Essex Study” by Essex County Council, show that pupils will find it difficult to focus and retain information, with teachers more likely to take days off sick with vocal strain and headaches.

The challenge lies in absorbing the lower bass frequencies that we sometimes experience coming from cars or noisy neighbours playing their music too loudly.

The ability of these frequencies to resonate and pass the energy through masonry walls, for instance, means that they can also pass through traditional suspended ceilings and bounce back into the room.

This high-energy, low-frequency sound is particularly disruptive to hearing impaired, ASD and ADHD students.

Part of the solution lies in utilising a bass absorber at strategic points within the classroom. In this instance Ecophon’s cost effective bass traps were placed behind Ecophon acoustic pin boards and rafts.

The result: not only does the classroom meet the required refurbishment standard of 0.8 seconds, but actually meets the 0.6 seconds for newly built schools, bringing this 100-year-old school into the 21st century. Increased attainment and improved pupil behaviour will undoubtedly follow.

Shane Cryer, Concept Developer – Education at Saint Gobain Ecophon


Suppliers and contributors

  • Barnes Construction
  • Beardwell Construction
  • Essex County Council Infrastructure
  • Delivery and Education
  • Directorate Teams
  • Ecophon (Acoustic Walls and Ceilings)
  • Gratnells (Educational storage supplies and Learnometer)
  • Learniture (for next generation learning spaces furniture)
  • Professor Heppell and Team
  • Thorlux Lighting

Main image credit: Gratnells