Lecture theatres, science laboratories and student unions are among UK university buildings shut because of crumbling concrete.
Sixteen universities have told BBC News they have closed or partially closed areas containing reinforced autoclaved aerated concrete (Raac).
Lectures have had to move to other areas of campus.
Some student accommodation has also been affected, as universities make areas safe.
The Department for Education (DfE) advised schools, colleges and nurseries in England to vacate areas known to contain Raac, unless suitable mitigating measures had been put in place.
Other public buildings across the UK, built or modified between the 1950s and the mid-1990s, are also affected.
Some shows have been cancelled, after the concrete was found in theatres.
St David's Hall in Cardiff has closed for checks, with comedian Adrian Edmondson, singer Alfie Boe and 1980s rock band Europe due to perform in the coming weeks.
More hospitals have also come forward to report they may have been built using Raac, and the government said it was working quickly to establish the scale of the problem.
