Obesity (Recreational Diving Guidance)

Obesity may exclude a candidate from diving as it frequently betrays a lack of general physical fitness. Additionally it may create difficulties when conducting a rescue either with the obese diver attempting to tow with an unconscious diver or when a diver is attempting to get an obese diver into the boat or to another place of safety.

A BMI (Body Mass Index) of more than 39.9 should exclude diving. Due regard should be taken to weight distribution, obesity concentrated in the abdomen should be less acceptable than evenly distributed fat and due allowance should be given to the individual whose excess weight is visibly muscular. Enquiry should be made as to the amount of exercise taken.

A BMI between 30 and 39.9 is not ideal but may be acceptable. The formula tends to discriminate against tall or muscular individuals. In these circumstances taking account of waist measurement may be helpful. A waist measurement in men of greater than 105cms and in women of greater than 90cms is a cause for concern and should be discussed with a Diving Medical Referee.

Qualified divers with a borderline BMI may be given a provisional pass for two or three months when they would be required to produce evidence of improvement to have their certificate extended.

To calculate BMI go to BMI www.nhs.uk and put BMI in the search box at the top right of the page or use the formula body mass index= weight (kg) / (height in metres)²

Reviewed January 2021