Poor ventilation and its health implications

Introduction

Ventilation has a very important role to play in every part of human being due to the comfort it provides in the house that is built to protect human’s health which can only be suitable for habitation when it meets the needs of its inmates. Regrettably a lot of houses are constructed without due consideration to proper ventilating openings thereby inhibiting proper circulation of fresh air. And this is due to a lot of factors.  Fabuwa  (2002) defined ventilation as the high process of replacing air in any temperature, replenish oxygen or remove moisture, odour, smoke, heat, dust, air borne, bacteria and carbon dioxide. Ventilation is used to remove unpleasant smell and excessive moisture, introduce outside air to keep interior building air circulating and to prevent stagnation of the interior air.

According to American Society of Heating, Refrigeration, and Air-conditioning Engineers (ASHRAE, 2013) Standard 62.1 ventilation is defined as the intentional movement of air from outside a building to the inside. Air is used for providing acceptable indoor air quality. Ventilation is necessary to dilute odours and limit the concentration of carbon dioxide and air borne pollutants such as dust, smoke, and volatile organic compounds (VOCs). Ventilation is often delivered to space by mechanical system which may cool, heat, humidify and dehumidify the space. Air movement into a building can occur due to uncontrolled infiltration of outside air through the building fabric or the use of deliberate natural ventilation strategies.

Stanke (2007) defined Poor ventilation in relation to individual premises as the inadequate supply of Oxygen that brings about stale and noxious odour in that building which is capable of causing some health complications such as asthma, Pneumonia, heart failure etc. thereby making man uncomfortable and exposing him to ill health conditions. Poor ventilation is mostly caused by poor or lack of proper building plans and construction due to poverty and lack of skills.

Increase in population result in poor housing construction thereby leading to the inadequate provision of ventilating opening in buildings because of the strive to maximize land use. Lack of technology made people settle in slums, troubled areas of the world, civil wars and bombing caused people to settle for sub-standard houses. Aibor and Olorunda (2006) Stated that the nature of housing in the rural areas generally are poor due to the absence or inadequate provision of ventilating opening thereby leading to the increase of incidence rate of communicable diseases such as tuberculosis, pneumonia, heart failure, etc.

World Health Organization (2000) is of the opinion that overcrowding and poor ventilation is a great problem of public health which leads to airborne disease, breeding and infestation of vermin’s. A good house should satisfy all the needs of inhabitants such as adequate ventilating openings, proper lighting, privacy, sanitary convenience and provision of adequate protection against- communicable disease, accidents and weather conditions. Poor ventilation can be improved through the provision of employment, proper planning, and resource allocation by government, rise in household income and reduction in the cost of building materials etc.

Conceptual framework

Ventilation is an important factor for human dwelling in a house. But despite its importance, adequate relevance is not given to it in the construction of houses thereby resulting to serious problems, both in rural and urban sectors. It is known to be tremendously harmful to man when neglected. Therefore it is widely acknowledged that adequate ventilation is essential for good life and a key requirement for an efficient living (Aibor & Olorunda, 2006).

Proper ventilation in houses is a globally accepted phenomenon and one fourth of the world’s population is living in abject poverty which is an indication of the poverty level and socio-economic standard of developing nations which Nigeria is a part of. Most of the houses especially in the rural areas are very substandard and lack proper ventilation which affects the health of its inhabitants. One aspect that constitute grievous problems in proper ventilation of houses is the affordability of adequate and efficient building materials to contrast good houses by the low income class which forms a large percentage of many nations particularly developing countries e.g. Nigeria (World Health Organisation, (WHO), 2008). The problem of adequate ventilation in rural area is generally at the peak which includes lack of adequate planning of houses; attempt to maximize land use, inability to consult the right quarters for approval of building plans and construction. Low socio-economic status people are more at risk.

Shillington (2001) defined housing as a building constructed within the laid down building regulation to occupy persons and their personal effects, possessing all their necessary sanitary conveniences, comfort, shelter, privacy, protection of life and preventing disease associated with housing. A suitable building for human inhabitation must keep up with the building regulation which includes the adequate provision of ventilation. Paramount recognition of housing standards in human development made several international bodies including the United Nations to make a declaration on its place among other issues.

Types of ventilation

Sherman (2012) classified ventilation under three (3) categories

• Natural ventilation.
• Mechanical ventilation
• Hybrid or mixed mode ventilation

Natural ventilation

This is the type of ventilation that occurs naturally i.e. from natural sources e.g. winds and thermal buoyancy force due to in-door and out door air density differences. Purposely built ventilating openings includes window, doors, solar chimneys, wind towers and trickle ventilators. This natural ventilation of buildings depends on climate, building design and human behaviour (Sherman, 2012). Cross ventilation is a type of natural ventilation which occurs where there are pressure difference between one side of a building and the other. Typically, this is wind driven effect in which air is drawn into the building on the high pressure leeward side. Wind can also be driven in a singled sided ventilation and vertical ventilation.

Back–to–back ventilation is an example of a poorly ventilated environment in which buildings are densely situated whereby three to four walls of the houses are shared with other buildings. In this environment natural ventilation is usually of low standard or absent. The environment with back-to-back ventilation is usually associated with poor air quality, unpleasant and musty odour (Kennedy, 2004).

Mechanical ventilation

This is the type of ventilation that occurs artificially through the installation of mechanical equipment or machines e.g. fans installed directed in window or walls, or installed in air duct for supplying air into or exhausting air from a room. The type of mechanical ventilation used depends on climate. For example, in warm and humid climate, infiltration may need to be minimized or prevented to reduce intestinal condensation (which occurs when warm, moist air from inside a building penetrates a wall, roof or floor and meets a cold surface). In this case, a positive pressure mechanical ventilation system is used. Conversely, in cold climates, ex-filtration needs to be prevented to reduce intestinal condensation and negative pressure ventilation is used conversely in cold climate. Air filtration needs to be prevented to reduce intestinal condensation for a room with locally generated pollutants such as bathroom, toilets or kitchen; the negative pressure system is often used. A balanced mechanical ventilation system refers to the system where air supplies and exhausts have been tested and adjusted to meet design specifications. A minimum negative pressure of 2.5p is often maintained relative to the corridor in an airborne precaution room for infections (Hess, 2011).

Mechanical or artificial ventilation according to Hess (2011) can be classified into:

1. Exhaust ventilation
2. Plenum ventilation
3. Balanced ventilation
4. Air conditioning
5. Exhaust ventilation: In this system, air is extracted or exhausted to the outside by exhaust fans usually driven by electricity. As air is exhausted, a vacuum is created which induces fresh air to enter the room through windows, doors and other inlets. Exhausted ventilation is usually provided in large halls and auditoria for removal of air. The exhaust fans are housed in the external walls high up near the roof which facilitate removal of the upper layer of the heated air.
6. Plenum: in this system, fresh air is blown into the room by fans so as to create a positive pressure and displace heat air. Plenum or propulsion system is used for supplying air to air-conditioned buildings and factories.
7. Balanced ventilation: This is a combination of the exhaust and plenum systems of ventilation. The blowing fan must balance the exhaust fan.
8. Air-conditioning: Air-conditioning is defined as the “simultaneous control of all or at least the first three of those factors affecting the physical and chemical conditions of the atmosphere within any structure. These factors include temperature, humidity, air movement, distribution, dust, bacteria, odour and toxic gases most of which affect in greater or lesser degree human health and comfort”. In air-conditioning, the air is first filtered and then saturated with water vapours. The excess of moisture is removed and the air is heated to the desired temperature before it is supplied.

Hybrid or mixed mode ventilation

Hybrid (mixed mode) ventilation relies on natural driving forces to provide the designed (design) flow rate. It uses mechanical ventilation when the natural ventilation flow rate is low (Schild, 2002). Hybrid (mixed mode) ventilation uses both natural mechanical ventilation processes. The natural and mechanical components maybe used in conjunction with each other or separately at different times of the day. The natural component is sometimes subject to unpredictable external weather condition which may not always be adequate to ventilate the desired space. The mechanical component is then used to increase the overall ventilation rate so that the desired internal conditions are met alternatively; the mechanical component may be used as a control measure to regulate the natural ventilation process, for example, to restrict the air change periods of high wind speeds.

Poor ventilation

This is the inability of contaminated indoor air to be replaced with fresh outdoor air to maintain good air quality due to the inadequate or improper building or constructions of houses which would result to damage in man’s health and properties. Poor ventilation exacerbates mental ill health among those living in the house that is poorly ventilated. Therefore poor ventilation is caused by poor housing.

The standard of housing in an area is usually a reflection of the health in such area. Studies have shown that negative aspect of built environment tends to interact with and modify health disparities compounding already distressing condition (Health Council of The Netherland, 2010). Poor ventilation does more harm than good to the inhabitant. Those who live in poorly ventilated building/premises are at a greater risk of developing chronic respiratory disease and premature death.

Fabuwa (2002), stated that adequate allowance is necessary in dwellings where people works, eat and take leisure. He added that when vitiated air occupies a room and its not replaced with fresh air, it deteriorates and conveys a sense of discomfort which could lead to headache, sweating, dizziness etc. it can also lead to the spread of meningococcal meningitis which is predominantly a disease of institutions such as schools and barracks where sleeping quarter are overcrowded. He identified good ventilation as a means of curtailing its spread. A poorly ventilated house is a contributing factor that causes mental illness and also prevents the development of normal family relationship. Students and individuals pursuit on the other hand cannot be achieved in a room that is damp, overcrowded and unconducive. Poor ventilation can also cause irritation, bad temper, mental unrest, behavioural personality disorder.

Causes/factors that lead to poor ventilation

According to Clark et al., (2002) poor ventilation can be, caused by the following factors

• Lack of a good house plan
• High level of illiteracy in the country
• Lack of sufficient funds
• Lack of good skilful personnel and man power
• Poor government policies and regulating framework.
• Poverty-low income level and unemployment.

Lack of good house plan

Most houses constructed in the rural areas and even in the urban areas are constructed without a good house plan thereby leading to negligence on the importance of proper ventilating openings such as windows and doors.

High level of illiteracy

Due to ignorance on the importance of living in a well ventilated building, people tend to live in houses that are not properly ventilated thus leading to problems associated with poor ventilation which includes tuberculosis, pneumonia, common cold, catarrh etc.

Lack of sufficient funds

Lack of sufficient funds (insufficient funds) is a key factor in the increase of poor ventilation because when there is insufficient funds one tends to maximize capital thereby creating very limited consideration to proper ventilation.

Lack of skilful personnel and manpower

When personnel employed to carry out the planning and construction of a building are not skilful in doing their work, the work is done casually without adequate consideration to ventilating openings and even when they are considered they are not properly constructed thereby leading to poor ventilation in the building.

A good number of the cause of poor ventilation in houses includes policy implementation, low income, financing, materials, labour, technology. The incidence of people living in houses which are poorly ventilated and unhealthy is in rapid succession in Nigerian. A proliferation of slums and squatter settlement due to continual migration  of people into cities and shortage of affordable houses for low income household and the poor who constitute over 70% of the urban population (Stanke, 2007).

Effect of poor ventilation on health and the social care

Some of the effect of poor ventilation as highlighted by Shawn (2004) includes:

• High prevalence of disease attack
• Exacerbation of mental stress
• Accident (home accident)
• Excessive heat and cold
• Educational attainment and deprivation
• Indoor pollution
• Communicable disease and ill mental state from coping with normal working life
• Airborne and contact borne disease such as tuberculosis, measles, cholera, scabies etc.
• Deterioration and conveyance of a sense of discomfort which could lead to headache, sweating, dizziness etc.

1. High prevalence of disease attack: Poor ventilation caused by inadequate ventilation openings and overcrowding of a room causes ill ventilation which serves as a route in the transmission of respiratory disease such as tuberculosis, asthma, influenza, etc. this result in an increase in the disease burden with the population, it also affects productivity thus perpetuating the cycle of poverty.
2. Exacerbation of mental illness: Since poor ventilation is also as a result of overcrowding and poorly constructed ventilating opening, this result in the disturbance of the brain cells thereby leading to irritation, intimidation and further complication such as mental disorder.
3. Accident: Overcrowding of the building with various materials, furniture’s or facilities due to lack of adequate space would lead to accidents especially among children.
4. Excessive cold and heat: Poor ventilation or inadequate ventilation in a house would cause excessive heat during the dry season thereby making the building uncomfortable for human inhabitation it gives an irritating feeling.
5. Poor educational attainment and deprivation: The poor design of a house and its lack of adequate ventilating opening often renders the learning environment un-conducive for learning especially during extreme weather condition these factors has serious health implication with attendant social and economic consequences including school absenteeism.
6. Airborne disease transmission: Poor ventilation which does not allow the free flow of air increases the rate of air borne disease transmission from person to person present in a particular place. E.g. tuberculosis, cholera, coughs etc.

Hazard associated with poor ventilation

According to Singh et al. (2005) the hazard associated with poor ventilation can have direct or indirect impact on health and they have potential of causing injury and damages to individuals exposed to them.

These hazards are not restricted to contamination and they include:

• Physical hazard
• Social hazard
• Biological hazard

Physical hazard

This hazard includes heat, cold, inadequate energy, efficiency, poisoning (carbon monoxide, lead) and similar physical hazards are caused as a result of poor ventilation in the house and maintenance of equitable temperature by cooling during dry season and wet season is also conducive to good health. Examples of the physical hazards are;

1. Heat: Building that are constructed without adequate consideration to ventilation e.g. lack of adequate large windows or doors constructed facing the south are likely to develop higher indoor temperatures and may carry greater risk to health.
2. Damp and mould: This type of housing related hazard tends to be worst in overcrowded dwelling often occupied by families of low socio-economic status. However, damp and mould has repeatedly been linked to a number of health outcomes including respiratory disorder, nausea, vomiting and generally in health.
3. Carbon monoxide (poisoning); poisoning by carbon monoxide occurs as a result of poorly ventilated and maintained combustion sources. (Gas boilers fire etc. which cause irritation of the eye and lungs, thus making the entry of disease germs easy.
4. Random: Radioactive gas which enters buildings from underlying soil and rock. When radio and its decay product are inhaled, they eradicate tissues in the body with the largest being delivered to the lungs.

Social hazard

Individual who lives in overcrowded house which reduces the free flow of air are prone to higher risk of being involved in offences due to the lack of improved occupant psychological and physiological needs

Biological hazard

The risk of transmission of communicable disease is high in a house that has poor ventilation and overcrowding. Overcrowding and poor ventilation are problems commonly associated with insanitary dwelling. It is exacerbated by an under supply of larger dwelling and impair ventilation (inadequate windows and doors in the house) they are of great problems in all phases of public health this is because, a house overcrowded with people is bound to generate a lot of solid and liquid waste whose magnitude is beyond the facilities men’s physio-mental performance and well being as over crowded house leads to sustainability and proliferation. They give rise to biological hazard. A house is said to be overcrowded when the vacant floor available for each adult is less than fifty. Square feet; children above ten year are counted as adult in this case (WHO, 2008). A house is said to be poorly ventilated when the supply of air (natural and artificial) is inadequate.

Measures to prevent poor ventilation in houses

The following measures are suggested by Israeli and Pardo (2011) to prevent poor ventilation in Houses:

• A good house must be well ventilated with adequate air openings such as windows, doors and other artificial ventilating equipment or materials such as fans, air conditions etc.
• The building should have adequate space so as to encourage the entrance and exit of fresh and stale air respectively.
• The house should be built far from any odour generation premises.
• Government should embark on programs that will help in arresting the problem of poor ventilation condition.
• There should be provision and implementation of building adoptive bye-laws.
• House owners and possibly dwellers should affect repairs on damaged parts of their building such as windows and doors.

Attitude of people towards poor ventilation

Poor ventilation in houses predisposes man to much ill health condition so it is not wrong to say that most of the houses have the problem of poor ventilation and overcrowding which may have influence on the health of the people.

The attitude in this content denotes the way of thinking and behaviour of people in relation to poor ventilation. Ignorance and technical negligence on the hand of builders and house owners are responsible for increase in the impact of poor ventilation in our society.

American Academy of Orthopaedic Surgeons (2011) observed that the poorest people in a community are usually found living in the quarter settlements and slums. It was also noted that the general public is not fully aware of the problems caused by poor ventilation in houses. The uncooperative attitude of the general public, environmental health officers toward good housing sanitation is the major problem facing poor ventilation and overcrowding in Nigeria (Aibor & Olorunda, 2006).

References

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