12061 Jefferson Blvd., Culver City, CA 90230-6219

Endorsement of Improved Test Methods and Slip Prevention Standards for New Flooring


The objective of this endorsement is to reduce the human and financial costs of slips and falls. Such accidents cause some 1200 deaths, and in the workplace alone about $3 billion in lost productivity and compensation costs, in the United States each year.


The Slip Resistance Committee of the Ceramic Tile Institute of America (CTIOA) is endorsing the following:


(1)   The variable-angle ramp laboratory test methods for slip resistance that are already a national standard in Australia, Germany, Italy, and New Zealand and a Final Draft standard in 17 other nations

(2)   The spillage volume displacement test that is a national standard in Australia, Germany and New Zealand

(3)   The detailed pedestrian slip-resistance safety standards for new flooring that are already national standards in Australia, Germany, and New Zealand


It’s necessary to know the results of (1) and (2) above to make full use of the safety standards in (3).


We request that manufacturers of hard and resilient flooring offered for sale in the United States supply potential buyers with slip-resistance category and (where appropriate) spill-volume displacement test results for the manufacturers’ products by January 1, 2003. As a substitute for the ramp test, manufacturers may use any alternative test, or combination of tests and calculations, that is scientifically proven to predict the results of the ramp test or to be as good as, or better than, the ramp test as an indicator of human traction potential.


The ramp tests would replace the horizontal pull-meter test, American Society for Testing and Materials Method C 1028-96, that U.S. ceramic tile manufacturers currently use for laboratory slip resistance testing of their products.


The safety standards that are based on the test results are useful in selection of flooring in ceramic tile, vinyl and linoleum, natural stone, terrazzo, and wood. Buyers of flooring products should use the recommended safety standards when selecting new flooring for commercial, industrial, and recreational applications. They should also consider using the standards for residential flooring, particularly in cases in which occupants are at high risk for serious slip-related injuries.



The Slip Resistance Committee of the Ceramic Tile Institute of America is tasked to advance and disseminate scientific knowledge of slip and fall issues in order to improve safety of walkway surfaces in the built environment, including floors, stairs, and pedestrian ramps.


Pedestrian slips occur from an unfavorable combination of the person involved, the activity the person is involved in, the environment, the footwear (if any), and the flooring. Most slip accidents occur when the footwear or bare feet and/or the flooring are wet or otherwise lubricated. Some manufacturers of flooring and floor coatings presently offer as catalog information slip resistance test results, dry and/or wet, based on test methods standardized by the American Society for Testing and Materials (ASTM).


Experience with U.S. test methods and safety standards for prevention of slip and fall accidents shows that improved test methods and safety standards are necessary. National Safety Council statistics indicate that some 1200 Americans die each year — an average of one death every seven hours — as a result of slip-and-fall accidents on the same level (not on a ladder, stairs, etc.). In the workplace alone, in 1998 slips and falls caused 313,335 injuries (an average of one every two minutes) and over $3 billion (or $340,000 per hour) in workers’ compensation and lost productivity (Ref. 1). Too many floors are potentially slippery under their normal conditions of use. The requests and recommendations below are in the interest of public safety.


Slip Resistance Standards for Specific Situations

The Slip Resistance Committee is endorsing the slip resistance and spill-volume displacement standards in “Classification Guide for Commercial and Industrial Areas” (Table 5 in Reference 2) and “Classification Guide for Public Wet Barefoot Areas” (Table 4 in Reference 2) for new hard and resilient flooring materials. Implementing the slip resistance and spill-volume displacement standards in those tables helps prevent slipping accidents that occur on walking surfaces under wet or otherwise lubricated conditions. These standards are specific to situations of environment and human activity that relate to the use of the flooring. Most of the standards have been used commercially (in Germany) since 1992 (Ref. 3).


The standards specify minimum slip resistance requirements for some 150 situations. For instance, relatively low wet slip resistance is allowed for areas that are nearly always clean and dry. Rest rooms require higher slip resistance. Busy commercial kitchens require still higher slip resistance, and some industrial situations, such as mayonnaise manufacture, require the highest level. For barefoot areas, locker rooms require relatively low slip resistance; stairs outside a pool area need higher slip resistance; and pool stairs leading into the water under certain conditions require the highest.


The standards are useful in selection of flooring in ceramic tile, vinyl and linoleum, natural stone, terrazzo, and wood. They are already national standards in Australia, Germany, and New Zealand. We recommend use of these standards when selecting new flooring for commercial, industrial, and recreational applications. They are also worthy of consideration for residential applications, particularly in cases in which occupants are at high risk for serious slip-and-fall injuries. This includes homes where there are young children who might run, disabled persons, and/or senior citizens who may have osteoporosis, be using multiple medications, or have other medical risks.


Flooring manufacturers can, at their option, supply variable-angle ramp test results to show in which of the standards’ slip resistant categories their flooring belongs. There are five categories (R9 thru R13, the latter being the most slip-resistant) for areas where shoes are worn, and three categories (A thru C, the latter again being the most slip-resistant) for barefoot areas. Some ceramic tile manufacturers who sell their products in the United States already offer this information on request or as catalog information. We request that all vendors of hard and resilient flooring offer such data by January 1, 2003.


Some flooring products have relief surfaces. These products are intended mainly for restaurant kitchens, commercial car washes, or industrial areas with frequent spillage of slippery substances (e.g. in food factories or oil storage areas). The raised areas on the flooring materials are usually two inches or less across. They provide traction, and the lower areas provide volume for dispersal of liquids. For relief surfaces, the amount of volume provided (in between the raised areas) for spillage dispersal is a significant safety parameter in addition to the ramp test results. For flat surfaces, which includes most flooring, there is zero volume for spillage dispersal.


Primary test methods

For testing slip resistance, manufacturers can use the variable-angle ramp test that is specified in the standards and is now a national standard test method in four nations (Australia, Germany, Italy, New Zealand) and a Final Draft of a proposed national standard (including several other test methods) in 17 additional nations (Refs. 4, 5). Reference 4 describes this test in general and Ref. 5 describes it in detail. Several laboratories in the United States, and many in other major flooring-producing countries, have in operation variable-angle ramps built to the existing standards. Two ramp manufacturers offer ramps for sale. Many of the world’s leading ceramic tile manufacturers now publish variable-angle ramp test result categories in catalogs for their floor tile products.


The variable-angle ramp method is a laboratory procedure for assessing traction on wet or otherwise lubricated flooring materials. Human subjects walk a three-foot-long flooring sample under specified conditions that include a standard lubricant. Each person repeatedly adjusts the angle of the ramp to find the steepest slope that he or she can walk on the test flooring without slipping. Each person who walks (tests) the flooring is first tested on a specified standard flooring each day before testing the subject flooring.


A scientific study published in 1989 (Ref. 6) validated the precision of the variable-angle ramp method. The study involved walkers of both sexes (70 males, 28 females), ages 18–58, weights 110–231 pounds, heights 5 feet 2 inches to 6 feet 8 inches, and a wide range of shoe sizes and body types. Statistical analysis of the results showed that by testing with two walkers, the acceptance ramp angle of typical flooring could be determined to within one degree. No other human traction test device has equaled, or even approached, a successful validation of this magnitude.


Appendix E in Ref. 5 specifies the spill displacement volume test method.


Alternative test methods

The Committee recognizes that these endorsements do not specify a field test. We plan to deal with that issue separately as soon as possible.


For catalog information and laboratory testing of new flooring, flooring manufacturers may use any other test method, or combination of test methods and calculations, that is scientifically proven to predict the slip-resistance category that would be determined using the variable-angle ramp tests; or to be (1) at least as good as the ramp method as an indicator of human traction potential and (2) relatable to the ramp safety categories. Such a method, if portable, would also be an obvious candidate for use in field testing.


You can obtain further information from, or make comments to, Ceramic Tile Institute of America in Culver City, California: telephone 310-574-7800, or E-mail ctioa@earthlink.net.




1.   Simpson, R., “An Ounce of Prevention,” Flooring, August 2000, pp. 24–25.

2.      Bowman, R., “An Introductory Guide to the Slip Resistance of Pedestrian Surface Materials,” Standard HB 197:1999, Standards Australia, PO Box 1055, Strathfield, NSW 2135, Australia. Email: sales@standards.com.au.

3.      “Guidelines for floors in work rooms and work areas with increased slipping hazard,” Code of Practice ZH 1/571, Main Organization of the Trade Associations, Central Office for Accident Prevention and Industrial Medicine, Alte Heerstrasse 111, 53754 St. Augustin, Germany, April 1989.

4.      “Ceramic tiles — determination of coefficient of friction, European Committee for Standardization CEN/TC 67 N. 161, February 1998, Milan, Italy.

5.      “Australian/New Zealand Standard: Slip resistance classification of new pedestrian surface materials,” AS/NZS 4586:1999, Standards Australia, Strathfield, NSW or Standards New Zealand, Wellington.

6.      Jung, K., and Schenk, H., “Objectification and accuracy of the walking method for determining the anti-slip properties of floor surfaces,” Zentralblatt for Industrial Medicine, Accident Prevention and Ergonomics, Vol. 39, No. 8, 1988, pp. 221-228. Contact CTIOA for English-language translation.