The building was evacuated by the hazardous materials response team, and five workers were treated on site before being taken to a nearby hospital. All five were later discharged.
Chlorine is used as a sterilising agent for the water often used in liquid cooling systems for computers and servers. But when exposed to air in concentrated quantities it evaporates, creating chlorine gas, which has been used as a chemical weapon in the first world war and several subsequent conflicts.
Chlorine gas attacks the lungs, reacting with the water in mucosal layers, creating hydrochloric acid which irritates the lung tissue and causes fluid build up, shortness of breath and eventual drowning.
The workers were treated for dizziness and shortness of breath, and given oxygen at the scene, according to reports.
“Five workers at our Maiden data centre were taken to a local hospital following possible exposure to fumes, which may have been released during a spill of a chemical used to clean the cooling systems,” said Apple in a statement. “The spill was quickly contained and poses no threat to anyone else at the facility.”
The data centre in North Carolina is one of several that Apple operates using renewable energy and, at 183 acres, is one of its largest. It is currently being expanded and is tasked with handling iCloud, iMessage and iTunes data, powered by a 50 megawatt solar power plant.
Apple also employs solar power within parts of its production line, including the sapphire screen manufacturing plant formerly owned by GT Advanced. The factory in Arizona suffered a fire last week isolated to the solar array on its roof.
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