An ice box lid closed on a worker's head and knocked her out moments later.

The waitress was helping her colleague sort through frozen supplies and leaned her head into the large container in Yasothon, Thailand, on September 2.

She initially held the lid but let go of it, thinking her companion was securing it as she rummaged through the box.

However, the heavy cover hit her head and held her face as she felt dizzy. She stood up holding her forehead and appeared to have recovered but 33 seconds later she collapsed onto the floor.

CCTV footage shows the woman passing out with her colleague rushing to carry her. She was taken to the hospital, and a doctor did a brain scan on her.

When the results came, medics said they did not find abnormalities and discharged her later.

Dr Teera Tangviriyapaiboon, a neurosurgery specialist at the Neurological Institute of Thailand, said that there could have been minor bleeding under the skull due to torn arteries.

She said: ‘The symptoms develop gradually, leading to unconsciousness. Such patients must see a doctor and undergo a brain scan for appropriate treatment.

‘In less severe cases, no lesions may be detected, but patients should still consult a doctor for caution.'