We regularly field emails and calls from individuals – students, citizen-scientists, and others interested in sensing – that ask for help in building a wearable sensor.  A number of investigators have tried this approach (here, here, and here, for example), with varying degrees of success. Most justify their efforts with a what is portrayed as a logical approach – the WHO (and countless others) say air pollution exposure is bad —> air pollution exposure is a function of human activity and isn’t measured well by sophisticated central monitors –> we must capture exposures on the person using wearable techniques –> this will lead to improved public health. Continue reading →