Case Studies - Assessment of Flooring in the Millennium Galleries, Sheffield

A number of factors come into play when specifying flooring materials for public buildings such as the new Millennium Galleries in Sheffield. Aesthetics are clearly important, as are durability and ease of cleaning, but from a safety point of view it is slip resistance which carries the most weight. The statistics are clear; over 30% of all non-fatal major injuries in Local Authority and HSE-enforced premises are caused by a slip, trip or fall at the same floor level.

At the request of Sheffield City Council, HSL scientists undertook an assessment of the slip resistance characteristics of the flooring of the Millennium Galleries prior to the opening of the building. Tests were carried out in a number of areas of the Galleries including the entrance foyer, restaurant, kitchens and lavatories. Two test methods are recommended for this type of assessment. The first involves the use of a pendulum with a rubber pad which swings across the floor surface and measures the coefficient of dynamic friction. The second instrument measures the micro-roughness of the floor which for a smooth surface, such as the terrazzo-type tiles laid in the Galleries, is typically less than 10 millionths of a metre.

Drawing on HSL's wide experience of interpreting slip resistance test results, it was concluded that the likelihood of someone slipping when the floors were clean and dry was very low. However, if the floors became wet then there was a significant risk of slipping. Clearly, certain areas of the Galleries flooring might become wet: for example the entrance foyer and lavatories, or, in the case of the cafe and bar, have drinks spilt on the floor. To overcome these potential problems, two approaches were adopted. A substantial area of matting was installed in the foyer to absorb water brought in by the public on wet days, and the flooring in areas of gallery where fluid contamination was likely was treated with an acid etching process to improve slip resistance in the wet by roughening the surface. The etching process had been tested by HSL in the laboratory prior to its application and further on-site testing showed a significant reduction in the slipperiness of the floor surface in the areas treated.

The Galleries opened to the public in April 2001 with displays tracing the history of the cutlery industry in Sheffield and a major exhibition of items loaned from the Victoria & Albert Museum in London.