An occupational noise evaluation study was carried out by Massey University students on locomotive engineers and on-board staff on the two main train sets operating on the Wellington Rail Suburban Network. All measurement results conducted as part of the study show full compliance with the criteria for workplace noise exposure prescribed within the Health and Safety in Employment Regulations 1995. The health and safety noise criterion level permits a maximum dose of 100% which is equivalent to 85 dB LAeq for a normalised 8 hour working day. The highest measured sound exposure was 13% of the total permitted exposure. All occupational noise measurements were observed and written accounts were taken by the three person investigation team. Observations revealed atypical behaviour of one participant which likely compromised one set of readings. This atypical result was removed from the analysis and therefore did not alter the study conclusions. Regardless, such observed behaviour from the study team, reinforces the value of observed real time field monitoring during collection of data.