The 69-year-old star performed a solo concert at Wolverhampton’s Civic Hall on Monday, where allegedly a “small number” of those in the audience fainted.
One Robert Plant fan gave an account to local publication Express and Star, claiming he couldn’t get into the 3000 capacity venue, so had to give up and go home.
He said: “In the first 20 minutes I saw six or seven people being carried out of the hall after collapsing.
“I go to a lot of concerts but I had never seen anything like it.”
The fan, called Scott Campbell, continued: “There was a large team of St John Ambulance people who were all kept busy.
“We tried the balcony but the only place to stand was behind a big pillar which blocked our view. We left after half an hour because we couldn’t see anything.
“I asked to see a manager because if there was a fire and you were in the middle of the hall, there would be no way of getting out. She said the fire doors would be opened but it looked to me as if they were already open.
“I’ve seen Robert Plant before but I was looking forward to seeing him on his home turf. I’ve not been to the Civic for a gig before and I don’t think I’d go again after that experience.”
The City of Wolverhampton Council have since released a statement, which said: “The Robert Plant gig at the Civic Hall was a sell-out and the venue was at capacity for this music legend. Just under 3,000 people attended.
“Unfortunately, as sometimes happens at busy, crowded indoor gigs, there was a small number of people who fainted due to the heat. St John Ambulance were on hand to provide first aid to anyone who required attention.
“While the Civic Hall meets the required health and safety standards, it is an 80-year-old building and improvements to the ventilation and heating system are part of the planned refurbishment scheme.”