Asbestos
The presence of and exposure to asbestos fibres and Manufactured Mineral Fibres ((MMF). Includes rockwool and glass fibre blankets. White, blue and brown forms of asbestos fibres included.
Impact on health
- These tend to occur a long time after first exposure.
- Inhalation of asbestos fibres can cause damage to the lungs and, at the more extreme, cancers.
- Affect the protective membrane surrounding the lungs causing plaques and fibrosis.
- They can also cause certain forms of lung cancer, including mesothelioma. MMFs are skin, eye and respiratory irritants and may cause dermatitis.
Causes
- Part of a wide range of building products found in older houses and flats.
- Located in places not likely to be disturbed.
- Sprayed coatings and partitioning.
- Chrysotile materials in positions at risk from damage or disturbance.
- MMF used in loft and cavity wall insulation.
Prevention
- Damaged or disturbed asbestos assessed for repair, sealing and enclosure
- Removal by licensed contractors
- Existing asbestos managed in situ
- Keeping a record of asbestos location in the building
- Protecting it from damage by occupants.
- MMF minimal possible exposure to fibres during maintenance, installation and removal.
Biocides
Threats to health from chemicals used to treat timber and mould growth in dwellings.
Impact on health
The potential for harm to human health varies depending on the particular biocide.
Causes
- Where biocides used incorrectly.
- Where a dwelling becomes occupied before the fumes have dispersed.
Prevention
Use of biocides should avoided wherever possible. Treatment of the cause or underlying problem will make their use unnecessary.
Lead
- There are two main sources inside dwellings – paint and water pipes.
There may be traces in soil close to busy roads or from older or industrial buildings close by.
Impact on health
When lead is absorbed it builds up in the body. It can have toxic effects on the nervous system and blood production. It may have a detrimental effect on mental or intellectual development in children.
Causes
- Lead paint on the inside and outside of older building
- Lead water pipes in older buildings
- Contamination of the soil
Prevention
- If paintwork is completely sound, covering over old lead paint is a safer option than removal.
- If the paintwork has deteriorated, removal will be necessary.
- Proper precautions taken during paint removal to prevent ingestion of airborne lead particles. This will also prevent the settling of lead particles in the building or on surrounding land.
- Lead pipework should not be present in dwellings. Installation of lead pipework is now prohibited in UK dwellings.
- Leaded paints are no longer generally available.
- EU legislation allows for the use of white lead in listed buildings.
- There are legal limits for the levels of lead in drinking water and guidelines for levels in soil.
- There is no UK guideline level for lead in house dust.
Radiation
The main source of harmful radiation in dwellings is from radon gas. Radon is colourless and odourless. It is not possible to detect it, either in the air or the water, without testing and measurement. Radon can dissolve in water. Airborne radon poses a more significant threat.
Impact on health
Potentially the second most common cause of lung cancer after smoking. There is also a possibility of causing leukaemia/acute lymphatic leukaemia/skin cancer. Variations in radon gas exposure depend to a great extent on geographical location. Some regions are more affected by radon than others.
Causes
- Natural sources account for 85% of the total exposure. The majority of which is from radon gas in buildings.
- Radon dissolved in private water supplies is only found in significant quantities in areas where levels of radon gas are high.
- While there is no completely safe level of radon, the risk is small where the average level of airborne radon is at or below 20 Bq m-3 .
- Radon gas occurs naturally in the UK, but the amount varies from place to place. Concentrations tend to be highest where the underlying rock is granite.
- Radon occurs naturally in very low concentrations. In confined spaces, it can build up and reach concentrations hazardous to health.
- Indoor levels depend on the concentration of radon in the ground.
- Levels affected by state of repair, level of heating and ventilation.
- Radon levels can vary between similar houses, even those in the same street.
- Lower atmospheric pressure within buildings draws radon gas in through holes, cracks and gaps in the floor. This occurs more with suspended timber floor. Any breaches of solid floors or damp proof membranes will allow the gas to enter the dwelling.
- Open chimney flues (whether used or unused), can draw radon-rich air from under the dwelling.
- Extractor fans can aggravate radon problems if a suitable air inlet is not provided.
- Problems with radon gas typically affect the lower storeys of a building. Flats located above ground floor level tend to be less affected.
- Radon is not found in major public water supplies at levels which pose a threat to health.
Prevention
- For existing dwellings, a radon sump, a hollow under the floor with a low power fan to disperse the gas into the open air.
- Increasing the air flow under timber floors.
- Installing a whole house positive pressurisation system.
- All new dwellings should achieve radon gas levels as low as is practicable. For existing dwellings in affected areas remedial measures should be adopted.
Fuel gas and other volatile compounds
Threat of asphyxiation from escaping fuel gas into the dwelling. Exposure to a range of organic chemicals (VOCs) following refurbishment of a property.
Impact on health
- Inability to breathe leading to asphyxiation.
- Short-term irritation and allergic reactions to the eyes, nose, skin and respiratory tract.
- Higher concentrations resulting in headaches, nausea, dizziness or drowsiness and can aggravate asthma.
Causes
- Defects to the gas installation or appliances.
- Exposure to fumes from paints, glues, solvents, etc.
Prevention
- Gas supplied by an authorised supplier. Standard composition and pressure.
- There should be appropriate pressure regulators, meters and pipework.
- Regular testing to ensure there are no leaks or other defects. In particular if there have been any alterations to the dwelling or to the gas installations.
- Appliances installed, serviced and maintained by a competent person.
- Adequate low level ventilation or means of ensuring any escaping LPG can drain away. Particularly important where the floor level is below the adjacent ground level.
- Detection which could provide warning to occupants if there is a gas is build up within the dwelling. Enabling occupants to take action and/or to escape. The appropriate siting of such detectors will depend on which gas is being supplied.
- Use of low emission materials and products.