Influence of ventilation use and occupant behaviour on surface microorganisms in contemporary social housing

Abstract

Homes satisfy our most basic needs for shelter and should be designed to provide a comfortable and safe environment. However, provision of housing is constrained through cost and legislation encompassing appearance, structure, materials, provision of services and energy performance. Most of the time these align to human needs, but there are conflicts, particularly with respect to energy and ventilation and their influence on health. In a bid to reduce energy and carbon emissions, the building sector is delivering increasingly airtight homes that aim to reduce uncontrolled ventilation losses 1. There are concerns that without improved designed ventilation provision this strategy may lead to a range of unintended consequences including impacts on occupant health 2. Ventilation affects exposure to a number of elements that are known to influence health, including chemicals, moisture, temperature and microorganisms. There is evidence that poor ventilation may be linked with poor physical and mental health in a number of non-domestic building types 3 , but whilst the literature points to detrimental effects in housing 2,4 , this remains seriously under investigated. In particular, there are currently gaps in knowledge about the range and diversity of microorganisms in the domestic environment, particularly in the context of modern airtight homes 5. People spend a great deal of time in their homes, especially those at the extremes of age, and therefore the indoor microbiome could impact upon human health in ways not yet understood 6. Recent research into the real world performance of buildings has begun to reveal significant performance gaps in environmental conditions, especially poor rates of ventilation, particularly in bedrooms 7. This has led to studies that have examined the consequences of increasing airtightness of modern construction, lack of ventilation, occupant interaction with ventilation, and increasing use of mechanical ventilation 8,9 .

Microbial, environmental and anthropogenic factors influencing the indoor microbiome of the built environment

“…The built environment designs affect not only the human microbiome, health, and behavior but also affect other associated macroorganisms like pets. So, human health can be made better by modifying the indoor microbiome through architectural design [35,50,52]. Efforts are going on to design selective pressures and use microbial resources to create a healthy symbiotic built microbiome [53].…”

“…Incorporation of well‐ventilated spaces into architectural designs has long been known to influence human health, wellbeing, and productivity [52]. Ongoing research tries to decode the influence of specific ventilation design on indoor microbial community structure and diversity.…”

Wind of change: Better air for microbial environmental control

“…The effects on health are different. When high counts of environmental bacteria, such as Staphylococcus epidermidis , Micrococcus and Flavobacterium, are found scattered on skin flakes, these can be considered indicators of inadequate ventilation [ 4 ]. Researchers have suggested that gram-negative bacteria, such as Pseudomonas aeruginosa , or other bacteria such as thermophilic actinomycetes, Streptomyces albus , Bacillus subtilis and complex communities of microorganisms in biofilms are aetiological agents of hypersensitivity pulmonary disease [ 5 , 6 ].…”

Microbes in the built environment

“…Surfaces in various rooms in the homes of older adults were sampled by Sharpe et al 15 . The samples were then examined using microbiological culture methods.…”