The pilot study involving compulsory face masks in several busy parts of Amsterdam and Rotterdam shows the use of masks did not lead to any change in behaviour, or a reduction in visitor numbers, the researchers said on Friday.

The mask requirement was introduced in shopping streets, markets and Amsterdam’s red light district in August, following a sharp rise in the number of positive coronavirus tests in the two biggest Dutch cities. People who refused to wear a mask faced a fine of €95.

Researchers at the Netherlands Institute for the Study of Crime and Law Enforcement, analysed surveillance camera footage and compared the results with areas where face masks were not required.

They found that when the pilot started, 55% of people wore a mask, but that this had risen to 75% by the end of the month.

However, one third of people with a mask did not wear it correctly over both their mouth and nose, the researchers found.

Visitor numbers

At the same time, there was no real difference in the number of people visiting any of the places where masks were compulsory, or in how well they kept to the 1.5 metre social distancing rule.

Shopkeepers had complained their sales were down up to 40% in the areas where masks were compulsory.

Rotterdam and Amsterdam were given the go-ahead to introduce facemasks in busy areas by the national government early in August as their coronavirus infection numbers spiked, to see what effect they had on distancing and public awareness.

The RIVM public health institute has never supported the use of non-medical face masks and the government has instead emphasised the importance of limiting visitors at home and keeping a 1.5 metres distance.

Note: this article was amended on Friday afternoon to rectify a misunderstanding.