Sleep disorders, above all obstructive sleep apnoea, present a significant safety risk through impaired judgement and excessive sleepiness and are associated with comorbidities that affect Safety Critical Work. A worker referred with fatigue, poor performance or incidents is assessed for the broad range of possible causes, medical conditions such as anaemia, diabetes, hypothyroidism, cardiac disease, chronic obstructive pulmonary disease and sleep disorders, psychological conditions including depression, anxiety and post-traumatic stress disorder, occupational factors such as rosters, shift work, sleeping arrangements, bullying and conflict, and social factors, then categorised and referred to the general practitioner as required; the chapter interfaces with the operator's fatigue risk management program required under the ONRSR safety management system guideline. Periodic Health Assessments, and Triggered assessments where indicated, include the Epworth Sleepiness Scale (0 to 10 normal, 11 to 15 mild to moderate, 16 to 24 moderate to severe sleepiness) and the STOP-Bang questionnaire to establish the risk of obstructive sleep apnoea and identify workers who should undergo a sleep study, using the polysomnography packages described (Table 21) and sleep physician input. The fitness criteria in Table 22 set the position for untreated and treated sleep apnoea by severity (apnoea hypopnoea index) and sleepiness, including the requirement for demonstrated CPAP or other treatment compliance which a triggered review may verify from device data, and for narcolepsy and other sleep disorders, for Category 1 and Category 2 workers.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.