Gravesend chemical cloud not harmful, say firefighters
A cloud of irritant gas accidentally released on Gravesend Pier prompted emergency crews to be called.
People were urged to keep windows and doors shut, and roads were closed with motorists told to avoid the area.
Kent Fire and Rescue said the gas could cause breathing problems, but it was more likely to affect those with pre-existing conditions.
It said the gas was not harmful but anyone who felt they had been affected should seek medical advice.
Nearby residents were advised to continue to keep windows and doors shut "for a further two hours", until about 23:00 BST.
The fire service said MDI isoscyanate, a component in expanding filler foam, had caused the problem.
It was being used by contractors to repair a floatation tank on a pontoon on the pier, it added.
The work was said to have caused a chemical reaction which created the gas cloud.
It is likely the chemical smell will remain in the air for several days, the fire service said, but it is "not harmful".
Kent Police provided support to fire crews.