The emergency incident took place last night at Whiteley’s Solent Hotel and Spa after two chemicals were accidentally combined, creating the noxious gas.
The leak sparked a ‘large-scale’ response from emergency services, with eight ambulances scrambled alongside more than a dozen firefighters and a specialist hazardous materials teams.
A total of 24 guests at the spa – including a number of children – were transported to University Hospital Southampton with ‘non life-threatening injuries’.
Now, the hotel’s general manager, George French, has insisted an investigation has been launched to find out how the leak took place.
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In a statement today, he told The News: ‘We evacuated all guests from the hotel on the instruction of the fire service and have been co-operating with them throughout the night and continue to do so.
‘Unfortunately, some of our guests who had been using the spa facilities yesterday evening were taken to hospital as a precautionary measure. Our main priority is our guests’ and team members’ health and wellbeing and we will share further information as soon as it becomes available.
‘This incident is under investigation so we are unable to release specific details but Solent Hotel is currently open and the spa and fitness facilities re-opened as normal at 8am this morning.’
As previously reported, firefighting crews were scrambled at 8.44pm following reports that a number of hotel guests had been ‘overcome by fumes in the spa area’ following the chemical mix-up.
Hampshire and Isle of Wight Fire and Rescue Service began immediate emergency care, set up a casualty handling area and requested the ambulance service to attend.
A ventilation fan was used to clear the fumes and firefighters took the vessel containing chemicals to fresh air. Gas monitors were used to check that the scene was safe.
Firefighters from Hightown, Fareham, Cosham, Portchester, St Mary’s and Romsey worked alongside paramedics and the hazardous area response team from South Central Ambulance Service (Scas).
Station manager Dave Graham said: ‘This was a large-scale incident with multiple people requiring medical treatment for the inhalation of gas.
‘We worked well alongside our colleagues from Scas and Scas hazardous area response team to make sure that everyone received the help they needed and to ensure that the scene was made safe.
‘We handed the incident over to the hotel management.’
The emergency came to an end at 1.27am.
Scas deployed eight ambulances, alongside four ambulance officers and its hazardous area response team.
A spokeswoman for the ambulance service added: ‘24 patients, ranging from children to those in their 50s, were assessed and treated by our ambulance teams for breathing difficulties. Following treatment at the scene by our crews those patients were taken to University Hospital Southampton for further assessment for those non life threatening injuries.’
The four-star venue ‘award-winning’ spa boasts eight treatment rooms.
Its hotel accommodation ranges from £130-a-night in one of the site’s ‘signature rooms’ to £205-a-night for a premier room.