The ward, which has been closed since early November to allow improvement works, was due to reopen shortly.
However, Manx Care said that routine checks carried out on Friday identified unexpected issues with air and environmental quality that require further investigation.
Manx Care said the findings meant it could not be fully confident in the recent test results. It said some patients attending hospital appointments may be more vulnerable to environmental risks, and that it would therefore be inappropriate to use the ward until the environment is confirmed to be safe.
As a result, Martin Ward will remain closed for at least one further week while additional cleaning is carried out and the environment is retested. The hospital team is also checking that all building systems are functioning correctly, with new assessments to be completed promptly and in line with the required standards.
Manx Care said it anticipates the delay will be around a week, but the position will be reviewed once testing has been completed.
Patients with clinic appointments scheduled to take place in Martin Ward will be contacted directly if any changes are needed. Manx Care has advised patients to attend their appointment as planned if they have not been contacted.
The organisation said services will continue elsewhere wherever possible and efforts are being made to minimise disruption. Clear signage will be in place at the hospital, and from Monday staff will be available on site to direct patients to the correct location.
Manx Care said patient safety is its highest priority and that the decision to delay the reopening had been taken as a precautionary measure. It acknowledged the inconvenience the pause may cause but said it was acting early and cautiously to avoid any avoidable risk to patients and staff.



.jpeg?width=209&height=140&crop=209:145,smart&quality=75)