The study examined exposure trends amongst a specific cohort of workers (n=55), loosely defined as "engineering trade" employees, but essentially comprising fitter and boilermaker trade disciplines at a variety of workplaces (n =6). Workers' perceptions of their noise exposure was surveyed, and factors likely to influence positive or negative HPD use behaviours. The goal being to identify determinants of Hearing Protective Device (HPD) use behaviour and potentially apply targeted interventions to increase the efficacy of a workplace's Hearing Conservation Program (HCP). Exposures for the study cohort were characterised utilising a combination of shift‐long personal noise dosimetry and short term area (at‐ear) measurements of specific tasks and activities. Risk perception and HPD use factors were examined utilising a questionnaire administered to study participants. Two distinct Similar Exposure Groups (SEGs) were confirmed, reflective of both fitting and boilermaker trade disciplines; both of which exhibited mean exposure confidence ranges wholly above the LAeq8hr 85dB(A) regulatory limit. Workers at the five workplaces where mandatory HPD use policies were implemented reported strong positive HPD use behaviours, and conversely at the sixth (and only) workplace where a mandatory HPD use policy was not implemented, negative HPD use behaviours were reported. On regression analysis this factor (mandatory HPD use policy) proved one of only 2 significant factors determining HPD use (p =<0.01). The research concludes that a mandatory HPD use policy is an essential element in predicting positive HPD use behaviours to ensure exposure control.