Overall the many studies that have been conducted on the microbiomes of the built environment have started to identify some general patterns regarding the microbes are found in various places.
[57] Pakpour et al. in 2016 reviewed the patterns relating to the presence of archaea in indoor environments (based on analysis of rRNA gene sequence data).
Factors that are thought to be important include humidity, pH, chemical exposures, temperature, filtration, surface materials, and air flow.
For example, it has been shown that people leave behind a somewhat diagnostic microbial signature when they type on computer keyboards,[71] use phones[72] or occupy a room.
For example, Diekmann et al. examined the connection between volatile organic emissions in automobile air conditioning units.
[citation needed] There are a growing number of research projects and groups focusing directly or indirectly on microbiomes of the built environment.