Table 1. Classification of divers or diving candidates based on severity of COVID-19 suspected illness. The categories of divers are based upon presenting symptoms and severity of disease, including oxygen requirement, imaging, need for and level of hospitalisation, and cardiac involvement. A diver should be placed in the highest category where they meet any (not all) of the criteria. BIPAP = bilevel positive airway pressure support; BNP = brain natriuretic peptide; CK-MB = creatine kinase MB fraction; CPAP = continuous positive airway pressure support; CT = computed tomography; DVT = deep venous thrombosis; ECG = electrocardiogram; ICU = intensive care unit .

Category 0 NO history of COVID-19-suspected illness	Category 1 MILD COVID-19-suspected illness	Category 2 MODERATE COVID-19-suspected illness	Category 3 SEVERE COVID-19-suspected illness
Definition:	Definition:	Definition:	Definition:
Divers who have no history of COVID-19 suspected illness should proceed with normal evaluations. Additionally, we would use these criteria in those who may have had a positive screening PCR or antibody test, but without any history of illness or symptoms consistent with COVID-19.	• Did not seek health care or received outpatient treatment only without evidence of hypoxaemia.	• Required supplemental oxygen or was hypoxic.	• Required mechanical (intubation) or assisted ventilation (BIPAP, CPAP) or ICU level of care.
	• Did not require supplemental oxygen.	• Had abnormal chest imaging (chest radiograph or CT scan).	• Cardiac involvement defined as abnormal ECG or echocardiogram, or elevated cardiac biomarkers e.g., troponin or CK-MB and BNP (or absence of documented work up).
	• Imaging was normal or not required.	• Admitted to the hospital but did NOT require mechanical (intubation) or assisted ventilation (BIPAP, CPAP) or ICU level of care.	• Thromboembolic complications (such as pulmonary embolism, DVT, or other coagulopathy).
		• If admitted, had documentation of a normal cardiac work up including normal ECG and cardiac biomarkers e.g., troponin or CK-MB and BNP.	• Thromboembolic complications (such as pulmonary embolism, DVT, or other coagulopathy).