Avoiding accidents with bath and shower mats

Assessing a bath or shower mat’s ability to reduce the risk of slip.

Bath or shower mats have seen a revival in recent years, with a wide range of colours, designs and materials now available. Indeed, it could easily be forgotten that these accessories often provide an important safety-related property – that of reducing the potential for a user to slip when getting into, out of or using a bath or shower. This factor is even more important when the elderly or young are involved.

For many years, bath and shower mats have commonly been labelled as ‘anti-slip’, ‘non-slip’ or similar, despite the fact that there is no formally agreed method of assessing the slip resistance of such products. This shortcoming is now a thing of the past. Work started by the British Standards Institute (BSI) in response to requests from Trading Standards (the UK enforcement authority for consumer product related problems) is now complete with the publication of BS 8445:2012 – ‘Bath and shower mats – Testing – Assessment of slip resistance properties’. The foreword of the standard states that is has been developed in order to set minimum performance standards that bath or shower mats shall meet – in an attempt to reduce the number of slip-related instances.

It specifies the slip characteristics, test methods marking and user instructions for bath or shower mats intended to be used inside a bath or shower during bathing or showering. Although the standard covers products intended for use in domestic, hotel and self-catering environments, it does not extend to items used in hospitals or care homes, which are excluded from the scope of the standard.

Product assessment

Testing is carried out using a ‘ramp’ method (figure 1). The mat is adhered as per the manufacturer’s instructions to a standard acrylic sheet intended to simulate a bath or shower surface. An ‘operator’ then walks barefoot backwards and forwards over the mat, while a solution of warm, soapy water flows across the surface. The ramp is tilted at an increasing angle until the operator slips or can no longer walk safely (termed the ‘angle of insecurity’ in BS 8445:2012.) The angle at which failure occurs is recorded, along with whether the feet slipped on the mat or the mat slipped on the acrylic surface.

The slip test is carried out five times and the mean value of the angle at which slip occurs is noted. The test is repeated using a second operator. If the difference between the mean values obtained by the two operators is greater than 2 degrees, the test is repeated.

The mean failure angle is used to specify minimum performance criteria and can also be mathematically related to the coefficient of friction.

Classification of bath/shower mat slip potential
Angle of insecurity	Dynamic coefficient of friction (CoF)	Slip Potential	Level
14 to 19 degrees	0.24 to 0.36	Moderate	Comfort
20 degrees and above	> 0.36	Low	Slip resistant

In order for a mat to be classified as being slip resistant, it must achieve an overall angle of 20 degrees or greater. Where an angle of between 14 and 19 degrees is achieved, a classification of ‘comfort’ is given. These mats are considered to have moderate slip potential.

The standard also requires mats to be sufficiently flexible to conform to the shape of a bath or shower tray, and to have a minimum size of at least 450 mm x 300 mm (bath mats) and 450 mm x 450 mm (shower mats), of which at least 300 mm x 300 mm shall be uninterrupted standing area. The standard also includes information on the markings that shall be present on an individual item, as well as informative labelling or user instructions that accompany the product. This includes information on care and maintenance of the product, instructions for use and any product specific warnings, such as the use of natural latex which may cause an allergic reaction in some individuals.

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