Many workplaces in New Zealand can be described as hazardous. That is, the nature of the work and/or workplace, or the combination of the two, can lead to situations where workers may be at risk of workplace accidents. One contributor to such accidents is worker fatigue, which is the result of the nature and intensity level of the work they are undertaking. This can be exacerbated by factors such as the length of the working day, shift work and roles that require high levels of concentration. Most existing risk minimization processes rely on self-reporting methodologies and health and safety procedures; neither of these are necessarily the most effective methods for dealing with workers in hazardous jobs and work environments. Wearable technology which collects physiological data, such as step and heart rates, as an individual performs workplace tasks has been proposed as a possible solution. While wearable devices are minimally intrusive to the individual and so can be used throughout the working day it is unclear how suitable they are for in-situ measurements in real-world work scenarios. In this work, we describe a series of studies conducted with New Zealand forestry workers and present an analysis of the data gathered to consider the suitability of the collection methods as well as the suitability of the data itself as a method to identify fatigue and reduce risk in the workplace.