The health problems associated with poor housing and home conditions, inadequate water supplies, flooding, poor sanitation and water pollution

HHSRS

Housing Health and Safety Rating System – a health-based risk assessment system for housing (in England and Wales)

Housing fitness

A set of basic requirements that homes should meet in order to be considered as acceptable places to live.  Often directly or indirectly based on health criteria

Housing and health

The relationship between housing and health is multi-faceted.  A healthy home needs to have sound structure, to be free of hazards, to provide adequate facilities for sleeping, personal hygiene, the preparation and storage of food, to be an environment for comfortable relaxation, for privacy and quiet, and to provide the facility for social exchange with friends, family and others.  The local environment is also important in determining such factors as fear of crime, access to local services and facilities and in promoting social interaction.

HHSRS

One of the most innovative initiatives on housing and health in recent decades has been the development in England (and Wales) of the Housing Health and Safety Rating System (HHSRS).  This is a health-based risk assessment procedure for residential properties, which replaced (in 2006) the previous housing fitness standard. Local authority Environmental Health Officers conduct risk assessments on rented, social housing and Houses of Multiple Occupation (HMOs)[1].

The HHSRS is 'a means of evaluating the potential effect of any faults on the health and safety of occupants, visitors, neighbours and passers-by'.

The principles which underlie it are that:

• any dwelling should be free from both unnecessary and avoidable hazards; and
• where any hazard is necessary and unavoidable, then the likelihood of an harmful occurrence and the potential harm which could result should be reduced to a minimum.

The HHSRS identified twenty-four categories of potential housing hazards.  Among the more important such hazards are:

Cold/ inadequate energy efficiency

(1) Cold
In Britain, as in many countries, there is a large winter excess of deaths and morbidity, many of which (around 25,000 deaths a year[2]) are attributable to the direct effects of cold.  Although limited, there is some evidence (and good theoretical grounds) to suggest that vulnerability to cold is greater in homes with inadequate insulation / inadequate home heating.  Measures to improve domestic energy efficiency and the affordability of home heating (i.e. reducing fuel poverty) are therefore expected to have appreciable benefits to health in terms of mortality and morbidity.

In England it is estimated that around 1 in 18 dwellings are below acceptable energy efficiency standards. The proportion is higher in older dwellings built before energy efficiency considerations were part of building regulation.

Heat

(2) Heat
The relationship between dwelling characteristics and risk of heat mortality/morbidity is not accurately defined, but is becoming an increasingly important consideration given expectations of higher summer temperatures as a result of climate change.  Dwellings that have large solar gain (south facing, large windows, rooms directly under poorly-insulted roof space) are likely to develop higher indoor temperatures, and may carry greater risks to health.

Falls and accidents

(3) Falls
A high proportion of accidents occur inside the home, and they are a particular concern for the elderly and children.  In England there are around 500 deaths, 230,000 injuries a year from falls on the stairs.   Falls on the level (tripping etc) account for 11% of non-fatal accidents and 2% of deaths in home. Although it is difficult to attribute the risk to characteristics of the dwelling, poor design and maintenance is a factor in many falls.

There are around 65,000 fires in dwellings a year, resulting in 600 deaths, and 15,000 non-fatal injuries.  Smoke alarms can help reduce deaths and injuries.

Damp and mould

(4) Damp and mould
Interpretation of the epidemiological evidence about the health effects of damp and mould is made more complex because damp and mould tend to be worst in over-crowded dwellings, often occupied by families of low socio-economic status.

However, damp and mould have repeatedly been linked to a number of health outcomes, including respiratory symptoms, nausea and vomiting and general ill health. Humidity in the dwelling can cause condensation which encourages the growth of fungal spores. Damp is also associated with an increase in house dust mites. Both of these are known allergens.  The prevalence of dampness varies considerable from country to country. In Europe, North America, Australia, India and Japan it is estimated that approximately between 10-50% of homes are affected by it.

Around 1 in 18 dwellings in England has appreciable dampness/mould (WHO 2009).

Carbon monoxide

(5)  Carbon monoxide
Poisoning by carbon monoxide occurs as the result of poorly ventilated and maintained combustion sources (gas boilers, fires etc).  In England and Wales there are believed to be around 40 deaths and 250 hospital admissions  a year from CO poisoning (Ghosh 2015), but the burden of morbidity and mortality is probably under-estimated in official figures.  Figures vary by country, however it is known that children and fetuses are particularly vulnerable.  There is uncertainty in the burden of disease due to CO poisoning, however it is thought that there are likely to be  significant adverse health effects such as certain neurological symptoms, from chronic low-level exposure to carbon monoxide in the indoor air. A paper by Croxford et al (2008) was the first study to quantify the association between the risk of CO exposure at low levels and the prevalence of community self-reported neurological conditions.

Radon

(6)  Radon
Radon represents one of the most important housing-related hazards.  It is a naturally-occurring, radioactive gas formed as part of the decay chain of uranium-238. It readily diffuses through air, is soluble in water and it can accumulate inside buildings.

It is a particular problem for dwellings in areas with particular geology (notably the south west and north midlands in the UK[3]). The health hazards are well characterised and result from the short-lived, chemically reactive isotopes of polonium, lead, and bismuth that are its daughter products. When inhaled or formed inside the lungs, these isotopes increase the risk of lung cancer.

Radon is thought to be the most important risk factor for lung cancer in Britain after smoking, accounting for around one in 20 cases.  At the action level of 200 Becquerels/metre³, there is approximately a 3% lifetime risk of developing cancer as a result of radon exposure.  Other malignancies resulting from these exposures may include leukemia (acute lymphatic leukemia in children) and skin cancer.  A number of engineering solutions are possible to reduce radon levels inside the home.

Other risks

Other housing related hazards (mainly with rarer occurrence or small/uncertain health effects) include:

• Asbestos and Man-made mineral fibres (MMMF) – a common material in older dwellings, but usually causing low level exposure unless disturbed
• Electromagnetic fields (EMF) – a ubiquitous exposure, though of variable intensity; uncertain epidemiological evidence
• Lead – mainly in old lead paint and water pipes/solder joints
• Chemicals in the home
• Other indoor air pollutants (e.g carbon dioxide   nitrogen oxides, volatile organic compounds and biomass burning products)
• Noise
• Electrical hazards
• Structural failure
• Entrapment or collision
• Explosions
• Uncombusted fuel gas
• Entry by intruders
• Hot surfaces and materials
• Domestic hygiene, pests etc
• Inadequate provision for food safety
• Contaminated water
• Inadequate lighting
• Poor ergonomics
• Crowding and space – a potentially very important factor that has bearing on the risks of accidents, fires, dampness and mould, mental well-being and a range of other adverse effects.

Designing for health

There are many factors that contribute to healthy housing (partly governed by building regulation), but there are some trade-offs in design.  For example, in general, higher energy efficiency is good for health (especially for lower income families that may struggle with fuel bills), but if energy efficiency means reducing ventilation rates, there may be adverse effects on indoor air quality, condensation and mould growth.

Affordability of housing

In addition to traditional risk factors associated with a dwelling, it should also be remembered that the home is one of the major areas of financial expenditure for families.  The lack of affordable housing and threat to many families of losing their home because of debts they are unable to meet has become an increasing problem, and one which often has substantial negative bearings on mental and sometimes physical health.