Background: Nursing workload remains an issue in current health care contexts. The use of quantitative methodologies, methods and tools to measure workload has not produced adequate data to inform workforce policy to resolve workforce concerns about workload. Objective: This study aimed to identify the influence of both culture and climate as factors in nursing workload. Methods: This research used an overall critical ethnographic methodology to investigate the real lifeworkload issues of nurses. Methods included fieldwork observations and informal discussions over a 3 year period and 11 in-depth interviews. Results: The study identifies the impact of safety mandates on nursing workload as an invisible phenomenon within current workload methodologies. Such mandates add to nursing roles and routines, and become a ‘taken-for-granted’ activity that is not always directly related to patient care, nor is a visible factor in workload measurement. Conclusion: Given that workload measurements are formulated on direct patient care activities, indirect and unrecognised activities may create additional nursing workload.