Carbon Monoxide and Nitrogen Dioxide are formed when fuels such as coal, wood, oil, and natural gas are burned. Most commonly these are produced in houses from open fires, wood burning stoves/log burners, gas hobs or cookers, and gas or oil central heating systems.

Particulate matter can be a mixture of both solid particles or liquid droplets suspended in the air that is mostly caused by burning fuel, cooking, and road traffic pollution. These particles are split into three main size categories based on the particle diameter and measured in microns (µm).These categories are PM10 (10µm), PM2.5 (2.5µm) and particles with a diameter less than 0.1µm - commonly known as Ultra Fine Particles (UFP). These particles enter the body through respiration, and depending on the size can cause issues in the lungs and even, in the case of UFPs, can enter the bloodstream causing issues throughout the body.

Volatile Organic Compounds are generally caused by cleaning and personal care products, building materials and other common household products such as cleaning products, air fresheners, deodorants, and other aerosol-based products. They can also be released over time from carpets and furniture.

Along with second hand smoke (SHS), Environmental Tobacco Smoke is well known for its negative health implications and trapping this smoke in an indoor area compounds these effects.

Radon is a natural radioactive gas that is colourless and odourless, formed and released from the earth as it decays. Radon is not an issue in outdoor air as it disperses easily but can become trapped in buildings built in geographical areas where Radon emissions are higher. It can affect buildings of all types but is often significantly more common in buildings with basements.

Indoor Air Quality (IAQ) refers to the cleanliness and healthiness of the air inside a building. It involves factors like airborne pollutants (dust, pollen, mould spores, VOCs), temperature, and humidity. Maintaining IAQ is crucial for occupant well-being and comfort. Key aspects include proper ventilation to exchange indoor air, control moisture, and enhance oxygen supply. Ventilation systems, including fans and filters, play a vital role in improving IAQ and involve effective ventilation strategies for minimising pollutant sources. Regular monitoring is essential for a healthier indoor environment.

Kitchen fans are designed to remove air from the kitchen that contains particulate matter and gases associated with burning fuels to improve the quality of the indoor air. Cooker hoods are designed to extract from directly above a hob and pull the air through a filter to remove the particulate matter. These can then either extract externally or recycle the filtered air back into the kitchen. If the cooker hood extracts externally at a rate of 30l/s or higher, you do not need an additional extractor fan in the kitchen. However, if the extractor fan recycles the air back into the kitchen or if you do not have or do not want a cooker hood, then an additional kitchen fan is needed. You can either install an intermittent extractor fan that achieves a minimum of 60l/s or a continuous flow extraction unit.

Calculating the minimum trickle flow rate for a continuous flow kitchen fan is again not completely straight forward, but as a general rule of thumb, set your trickle speed for a minimum of 13l/s if in doubt - this will more than meet the building regs threshold.

If you have a longer duct or a larger than average kitchen, then it may be worth seeking advice on suitable extraction rates which can be calculated for you through a specification based on the room size and duct lengths involved.

Radon is a naturally occurring radioactive gas that in its natural state is colourless, odourless, and tasteless. This makes it imperceptible to human senses, and individuals may not be aware of its presence without testing. Radon gas increases the risk of lung cancer if exposed to high levels over prolonged periods and smokers or individuals with pre existing respiratory illnesses are at a higher level of risk from exposure. It is formed by the decay of uranium, a radioactive element found in varying amounts in soil and rock. Radon can migrate from the ground into buildings, where it may accumulate to potentially harmful levels. It can affect buildings of all types but is often significantly more common in buildings with basements.

Radon levels can vary geographically, and certain areas may be more prone to elevated radon concentrations due to the local geology. It is essential for property owners, especially in radon-prone regions, to test for radon regularly.

Radon testing kits are available for use in homes and other structures. If elevated levels are detected, mitigation techniques, such as increased ventilation and the installation of radon mitigation systems, can be implemented. Because radon is a potential health risk, individuals are encouraged to test their homes for radon regularly, especially in areas where elevated radon levels are more common. It is important to use a kit that will be tested in a validated laboratory.

If you want to check whether you are in a geographical area prone to Radon, or if you need to order an accredited domestic test kit, you can order a report based on your address at the UK Health Security Agency website in the link below.

https://www.ukradon.org/

If you have completed a test and the results show an elevated Radon level, please feel free to contact us and we will be happy to look at suitable systems to combat this issue for you.

Volatile Organic compounds are generally caused by cleaning and personal care products, building materials and other common household products such as cleaning products, air fresheners, deodorants, and other aerosol-based products and even carpets and furniture. You can try to avoid bringing sources of VOCs into your home, but this is not an easy task without completely changing your way of life! The simpler option is to integrate a suitable whole-house ventilation system to effectively extract VOCs from your home.

Many fan systems that use filtration are supplied with filters that can be either replaced or are washable and reusable, but not all. Depending on the type of filtration being used, some filters will have to be disposed of and replaced periodically. It is always worth checking with the manufacturer to confirm whether a specific filter can be reused or not.

If you are installing a grille to an external vertical surface, then no resistance grilles are best. These grilles help to minimise backdraughts while causing no airflow impedance by keeping an open aperture for the out-going air. In contrast, gravity grilles incorporate hinged slats that fall closed when the fan is not in use and are blown open when the fan is in use. The downside to these grilles is that the fan has to push the slats open causing back pressure in the ducting which can put a fan motor under undue strain and shorten the life of the unit while also reducing the fan’s extraction rate. The slats can also clack in higher winds, causing an irritating noise.