"HUMAN error" has been blamed for an incident at Louth's Kenwick Park Hotel, which led to five people being treated for the effects of chlorine inhalation.
Three members of staff and two members of the public were treated at the scene before being taken to Grimsby's Diana, Princess Of Wales Hospital for precautionary treatment.
Hotel owner Stuart Flynn told the Grimsby Telegraph the "chlorination" had been the result of a member of staff incorrectly mixing chemicals – including chlorine – in the plant room of Kenwick Park's swimming pool.
Humberside Fire And Rescue, which said the chemicals involved meant the leak was classed as a "major incident", were called to the scene at 3.30pm, sending six appliances.
The hotel was due to be open as normal today.
Speaking at around 6pm yesterday, Mr Flynn said: "A member of staff got the mixture wrong in the plant room, releasing the chemical.
"It was human error.
"One of the leisure club operators got the mixture wrong when preparing some chemicals and there was a reaction, so we evacuated and alerted the fire brigade.
"There were an awful lot of fire engines, but they have now handed the building back.
"We evacuated as a precaution and it was all done very efficiently.
"We told people to come out of the pool, and they did.
"Everyone has been very sensible and very helpful.
"Three employees have gone to hospital to be checked for inhalation and we expect them back soon."
He added there had never been an incident of this nature at the hotel before.
He said: "We have been here 19 years and this has never happened before so we have got a good record.
"The operator obviously made a mistake.
"We're all human. If you're not absolutely careful these things can happen."
Steve Wright, incident commander with Lincolnshire Fire And Rescue, of Louth, confirmed the leak had been as a result of an accident.
He said: "We had accidental mixture of chemicals in the plant room of the pool.
"It caused a gas to be released affecting three members of staff and two members of the public who have gone for treatment.
"It's what we would call a haz mat (hazardous materials) incident, which we would class as major due to the chemicals involved. That doesn't necessarily state how big the incident is, but procedures apply because of the chemicals involved.
"We gathered information and made the scene safe.
"Hopefully everyone will be okay and as far as we are aware they will be."
A spokeswoman for Grimsby's Diana, Princess of Wales Hospital confirmed five people had been seen at A&E following the incident.
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