Pool cleaning fluids have been blamed for a chemical incident which led to the closure of King’s Road yesterday.
Firefighters were called by the Harbour Hotel on Brighton seafront at 12.30pm when a gas alarm went off there.
This afternoon, East Sussex Fire and Rescue Service said the alarm was sparked by disinfectant chemicals used in the hotel’s pool and spa.
A spokeswoman said: “We were called to the Harbour Hotel, King Road, Brighton at 12.30pm following reports of a gas alarm sounding.
“Crews from Roedean, Brighton, Hove, Lewes, Eastbourne, Newhaven and Battle attended.
“The service attend an incident related to the storage of disinfectant chemicals used in connection with pools and spas.
“Crews used four gas tight suits and two breathing apparatus to carry out decontamination of the area.
“Crews left the scene at approximately 4.49pm.
“The hotel has issued a statement to say that the scene is now safe and that the hotel is open to the public.”
The incident closed the A259 for four hours.
Six fire engines were at the scene and Kings Road was closed, initially just the eastbound carriageway but later the entire road, causing gridlock in the surrounding areas and delays across Brighton.
The operation was scaled down from 3pm, and firefighters left the scene and the roads reopened from about 4.30pm.
A spokesperson from Brighton Harbour Hotel said: “A staff member from the hotel had called the fire services, following a report that the hotel’s fire alarm system had been activated.
“The fire services attended the site to investigate further, with the decision made to shut off the road while they do so.
“All safety checks have now been carried out and the East Sussex Fire and Rescue Service have confirmed that it is safe to re-open; with the full hotel having been handed back at 4.35pm and now returned to normal service.”