Four people have been taken to hospital after chemicals inside a Guy’s Hospital plant room were mixed in a way that produced chlorine gas.
London Fire Brigade (LFB) said several people who came to the aid of a member of staff were treated for inhalation of the gas.
London Ambulance Service (LAS) said it treated nine people at the scene and took four patients to hospital.
Guy’s and St Thomas’ NHS Foundation Trust said the site has now reopened.
Around 150 people were evacuated from the basement and ground floors of the hospital, near London Bridge railway station.
Two fire engines, two fire rescue units, a command unit and specialist hazardous materials officers were sent to the hospital following the incident just before 09:00 BST.
Firefighters carried out a sweep of the area “to check for no elevated readings of chlorine gas”, the building was ventilated and the incident was contained just after 11:00.
LAS said in a statement: “We treated nine people at the scene. We took four patients to hospital and discharged the other five patients at the scene.”
Guy’s and St Thomas’ NHS Foundation Trust confirmed the chemical incident happened in a “non-patient area” of the hospital.
It added in a statement: “One staff member was injured and several people, who came to the aid of the person, were treated for the inhalation of chlorine gas.
“The site has now reopened and people should attend their appointments unless they are contacted by us directly.”
Guy’s is a 400-bed major London teaching and research hospital that provides cancer treatment and other services including dentistry and orthopaedics to patients.
