Evaluating radio wave exposure in public transports in Melbourne

Project background and aims: Mobile phone telecommunication is the main sources of personal radiofrequency-electromagnetic field (RF-EMF) exposure across different micro-environments globally.1 There is ongoing research evaluating if RF-EMF exposures associated with mobile phones is a potential health risk. The RF-EMF exposure from mobile phone technology generally involves downlink (DL) and uplink (UL) exposures. The former is due to the exposure emission from mobile phone towers, whilst the latter is due to the exposure emission from mobile phone handsets. Mobile UL exposure in public transports has been reported to be considerably higher than several other human micro-environments (e.g., residential area, park, shopping street, etc.). Though several studies have indicated this, there is a lack of detailed data on RF-EMF exposure during commuting in public transport, to or away from the Melbourne CBD at different times during the day. The Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) has been conducting targeted research, including assessment of personal RF-EMF exposures in human micro-environments, to monitor community RF-EMF exposures. As part of this research, it aims to conduct personal RF-EMF exposure assessments in different modes of public transports (e.g., selected tram and bus routes). The aim of this honours project is to evaluate personal micro-environmental RF-EMF exposure in trams across Melbourne. Methodological approach: A purposive sampling of 12 tram lines (covering all directions) will be selected from a total 25 tram lines in Melbourne. Each tram route will be travelled (from the one end to the other end) for three times a day (journey start time windows): morning (8:00-9:30), noon-early afternoon (11:30-15:30), and late afternoon (16:00-17:30). The morning and late afternoon involve the RF-EMF measurements of busy public commuting times (e.g., commuting hours to/from work); whereas the noon-early afternoon involves the measurements during non-busy hours. The measurements of the morning and the late afternoon will also help evaluate RF-EMF exposure on trams when a large number of people commute to and from city during school/office hours. On the other hand, the noon timeslot will be used to evaluate RF-EMF exposures during non-busy hours. The measurements will also be conducted at two tram station locations (last tram station after ‘morning’ on-tram measurements is completed, and the tram station at the start of the journey (noon-early afternoon). An ExpoM-RF4 dosimeter will be used to measure electric field intensity (V/m) of RF-EMF exposure sources across 30 frequency bands (80 MHz to 6 GHz). The ExpoM-RF4, placed in a small waist bag will be attached across the front chest region (while sitting/standing/walking) of the researcher while s/he travels on a tram during the conduct of the RF-EMF measurements. The researcher will turn off his/her personal mobile phone (flight mode active) during the measurements. The measurements on the tram will be conducted during the entire tram journey, whilst the tram station measurements will be conducted for 20 minutes. Each tram journey measurement will have a Journey Info Sheet for each on-tram measurement to record journey and measurement related relevant information (e.g., time of measurement, approximate number of travellers on the tram, researcher standing or sitting, proportion of people using mobile phones (only making/receiving calls or only using it but not making making/receiving calls) etc. Data analyses will compute and compare summary statistics (mean/SD, median/25th, 75th and 95th percentiles) of personal exposures on tram and at the tram stations during different timeslots of the day. The exposure levels will be grouped into several categories (based on RF-EMF exposure sources): total – sum of all measured frequency bands; mobile DL- sum of all DL frequency bands; and mobile UL- sum of all UL frequency bands, broadcast-sum of all radio and TV frequency bands; others-sum of the rest of the frequency bands. Further, statistical analyses (e.g., correlation and regression) will be conducted to evaluate the relationship and effect of local population density and the number of mobile phone towers (such as <500 m away from the travel route) on RF-EMF exposure levels. Necessary knowledge and/or skills: The honours candidate is expected to have general understanding of human environmental exposure to physical substance (e.g., radiation or radio waves). S/he is expected to have willingness to learn and use a device to measure radio wave (i.e., RF-EMF) in the environment during the study. Since the research involves travelling on a tram, it is a requirement that the candidate must be ready to travel (Myki expenses will be reimbursed by ARPANSA) on a tram while collecting data. Ethics approval is not required.