Standardized methodological frameworks including the UK Health and Safety Executive Management Standards (HSE-MS) have been proposed to aid comparison across organizations in quantifying job stressors. In contrast, the measurement of job strain (and job-related well-being) has been characterized by lower standardization, resulting in multiple conceptualizations and indicators. Here, we evaluated the psychometrics of the Italian adaptation of Warr’s (1990a) Job-related Affective Well-being Scale (W-JAWS), and its suitability as a job strain indicator to be integrated with the HSE-MS approach. In line with previous studies, data from 541 civil servants supported a 4-factor measurement model (i.e., Anxiety, Comfort, Depression, and Enthusiasm), and highlighted linear relationships with multiple HSE-MS risk indicators (i.e., Demand, Control, Peer Support, Change, and Role). Overall, our findings qualify the W-JAWS as a suitable standardized job strain indicator tool, which could be used synergically within the HSE-MS approach to provide comparable results across organizations and countries.