Problem Addressed

Many people suffer from poor indoor air quality (IAQ) leading to health problems for the individual and high costs (sick leave, medical costs) for wider society. Awareness of the importance of IAQ and related symptoms is on the rise in the UK, where the incidence of asthma is among the highest in the world.  

 common cause of poor IAQ is the spread of chemical and/or biological agents from the building itself into the indoor air. The problem is often, but not always, due to building moisture. How can we address symptoms of building related illnesses (BRI) such as asthma, skin and eye irritation, fatigue, concentration difficulties?

Solution Overview

The cTrap (surface emissions trap) cloth is a functional fabric that improves the indoor air quality (IAQ) by capturing and binding harmful airborne chemicals that are spread from the building into the indoor air. The problem is particularly pronounced in damp buildings. cTrap is a four-layer laminate in the form of a cloth, delivered on a roll. The cloth is attached indoors on walls, floors and/or ceilings, depending on where emissions are originating. A flooring of choice can then be laid over the cTrap cloth or, when the emissions are coming from the wall or ceiling, a thin plasterboard. With fast installation and direct effect, cTrap ensures a clean and healthy indoor environment, without using chemicals or consuming energy.  

cTrap is a laminate of two functional layers – one adsorbent layer and one layer of a hydrophilic polymer – plus one inner and one outer protective layer. It is air tight and stops and adsorbs all emissions, including volatile organic compounds (VOC), that are being spread from the surface to which the cloth is being attached. At the same time, the cloth allows water vapour to pass through with almost no resistance at all. The cTrap thus does not affect the moisture balance of the building, and there is no risk of water condensation which might lead to mould growth. The cloth can be attached on any surface.  

The product contains no chemicals, and no chemicals are used during installation. Furthermore, the cTrap works without consuming energy and stops and binds emissions irreversibly. The manufacturing process also bears environmental impact in mind, using exclusively renewable and recycled products. cTrap is a result of Prof Lennart Larsson’s research at Lund University, Swedenand there is a wealth of scientific documentation as concerns adsorption efficiency, water vapour resistance, air tightness etc. 

cTrap is a unique product which solves IAQ problems which are due to spread of chemical and/or biological emissions from the building itself into the indoor air.  It is a unique product developed from a PhD project at Lund University Sweden. cTrap is patented in the UK, most EU countries, North America, and China.  

Case Study

Example case studies:  

  • wooden house with a “summer cottage” mould-like smell indoors. The building had previously been treated with preservatives that, under moist conditions, form highly odorous chloroanisoles. The ceiling, walls and floor in the bedroom, but not living-room, were covered with cTrapTetrachlorophenoltrichloroanisole, and pentachloroanisole were detected in the air of the living-room, but only tetrachlorophenol was found in the bedroom, and in a concentration 93% lower than in the living room. The mouldy odour disappeared immediately following the cTrap installation.  
  • A building where a tar layer had been attached onto aconcrete slab, as moisture barrier. The air concentrations of polycyclic aromatic hydrocarbons (PAH) were 1726 ng/m3. The disturbing smell inside the building persisted even after the tar had been removed. The cTrap cloth was installed on about 75 percent of the wall surface, the smell disappeared, and the PAH  concentration decreased to 139 ng/m3, a reduction of 92%. 
  • townhouse where the tenants suffered from itching and headaches when at home. A PVC flooring had been glued onto the concrete slab which had become moist through diffusion of water from the ground. The air concentration of 2-ethylhexanol, a compound formed by hydrolysis of glue and/or phthalates, was 63 µg/m3. cTrap was attached onto the existing flooring, the air concentrations of 2-ethylhexanol decreased to 1.5 µg /m3, and the symptoms disappeared. The same low value was found in a follow-up study 6 years later – and the tenants still reported no symptoms. 

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