Spring 1997

Spring 1997

As a result of the NIST workshop, Geoffrey Frohnsdorff and Jonathon Martin submitted a Report from the Workshop, that was issued in March 1997, Seeking Validation and Consensus on Slip-Resistance Measurements and Standards; Report from the Workshop on: Evolution of Slip-Resistance Standards, which NIST then published as an internal report, otherwise known as NISTIR 5988. The Introduction to that report has been reprinted below for informational purposes. Please contact NIST for a full copy of the report.

Introduction

Injuries resulting from slips and falls are among the most common injuries suffered by U.S. citizens. The large magnitude of the economics losses can be deduced from workers compensation claims reported by a single private insure [1] who is believed to have about 10 percent of the private insurance business. For this insurer, claims resulting from slips and falls in 1990 accounted for 17 percent of the number of claims, and about 28 percent of the total cost (about $650 million) of claims for workplace illnesses and injuries. From the total cost of the claims in 1990, it may be estimated that the cost to the whole private insurance industry of claims for injuries resulting from slips and falls in the workplace is of the order of $6 billion/year. This figure, which does not include the cost of injuries from slips and falls outside the workplace, is only quoted to suggest that anything that could be done cost-effectively to reduce the frequency of slips and falls, and the seriousness of injuries resulting from them, would be of substantial economic importance in addition to its importance in reducing pain and suffering.

While reducing the number of slips and falls and the injuries resulting from them is clearly a worthy goal, it has been given new emphasis with the publication of the "National Construction Goals" by the Subcommittee on Construction and Building of the Committee on Civilian Industrial Technology of the National Science and Technology Council [2]. These goals are:

50% Reduction in Delivery Time;

50% Reduction in Operation, Maintenance and Energy Costs;

30% Increase in Productivity and Comfort;

50% Fewer Occupant Related Illnesses and Injuries;

50% Less Waste and Pollution;

50% More Durability and Flexibility;

50% Reduction in Construction Work Illnesses and Injuries.

In a commentary concerning the goal of "50% Fewer Occupant Related Illnesses and Injuries," the report stated:

"Buildings are intended to shelter and support human activities, yet the environment and performance of buildings can contribute to illnesses and injuries for building users. Examples are avoidable injuries caused by fire or natural hazards, slips and falls,....."

and, in connection with the goal concerning "50% Reduction in Construction Work Illnesses and Injuries," which includes slips and falls, the report stated:

"... although the construction workforce represents about 6 percent of the Nation's workforce, it is estimated that the construction industry pays for about one-third of the Nation's Workers' Compensation. Worker's Compensation Insurance Premiums range from 7 to 100 percent of payroll in the construction industry. Construction workers die as a result of work-related trauma at a rate that is 2-1/2 times the annual rate for workers in all other industry sectors (13.6 deaths per 100,000 construction workers, as compared to 5.5 deaths per 100,000 workers in all other industry sectors.) Construction workers also experience a higher incidence of nonfatal injuries than workers in other industries."

It seems obvious that if the National Construction Goals are to be achieved, serious attention must be given to reducing the number of injuries from slips and falls.

While it is not known precisely what fraction of slips and falls are a result of slipping, a 1977 publication of the National Safety Council [4] quoted in Reference 3 of the present report, stated that "In more than half of the falls, slippery surfaces were identified as a major contributing factor." If this is still the case, understanding and quantitative knowledge of the factors contributing to slipping should be important in seeking to reduce the frequency of slips and falls. An indication of the large number of possibly significant variables can be obtained from the list given in the recently-issued ASTM F1694-96, Standard Guide for Composing Walkway Surface Evaluation and Incident Report Form for Slips, Stumbles, Trips, and Falls [5]. The list of factors includes:

footwear sole

maintenance record

footwear heel

handrails/guardrails

walkway type

weather conditions

walkway construction material

safety program

walkway load

signs and warnings

walkway surface

Walkway illumination

surface levelness

natural outdoor light

surface textures

number of people involved

surface contaminants

Because of the number of possible factors that may influence the sequence of events in any slip and fall occurrence, and the difficulty in collecting reliable data about them, much remains to be learned about this subject. It is generally agreed that there is a need to be able to measure the "slipperiness" or "slip-resistance" of surfaces involved in human locomotion, but agreement is lacking about how to define slip-resistance, or how to measure it and standardize its measurement. This lack of agreement probably hinders progress in reducing the number of slips and falls because of the time and effort expended trying to develop appropriate standards, and because it raises questions about the significance of the data that are collected. Also, the lack of agreement on appropriate test methods leads to confusion in the presentation of evidence in law suits, and hinders the development of rational regulations and codes relating to slip-resistance.

The difficulty in establishing slip-resistance criteria for use in building codes was pointed out in a recent letter (see Appendix VIII) from the Vice President, Codes and Standards, of the Building Officials and Code Administrators International, Inc., in which he stated that:

"... there is a lack of consensus among interested parties, including manufacturers of products affected by this regulation and experts in the field, on appropriate performance criteria, test apparatus and acceptable thresholds. The regulatory community cannot be expected to adopt any particular proposal when the industry is in such apparent disarray."

The extent of the "disarray" is indicated by the number of committees in ASTM (the American Society for Testing and Materials) that are developing standards for slip-resistance. The committees include

C21 on Ceramic Whitewares and Related Products

D01 on Paint and Related Coatings, Materials, and Applications

D21 on Polishes

F06 on Resilient Floor Coverings

F08 on Sports Equipment and Facilities

F13 on Safety and Traction for Footwear

Because of the disarray, an author of this report (GJF), asked several persons who are actively involved in standards activities related to slip-resistance if it might be helpful to hold a workshop to discuss what could be done to clarify the situation. With encouraging responses, the decision was made to organize the workshop described in this report.

ASTM Committee On Standards (COS)

In April of 1997 the Committee on Standards at ASTM held a meeting in the interest of reducing the confusion this has caused. The Committee on Standards at ASTM is interested in reducing overlap in the various standards and fostering a cooperative approach in the development of sound technical standards to aid in the advancement of public safety. COS developed a Management plan for effective communications and coordination between technical committees developing slip resistance standards for pedestrian purposes. The COS management plan has stated that its objectives are to:

Ensure that committees develop slip resistance standards only within their main committee's scope of activity;

Maximize communications between committees developing slip resistance standards;

Coordinate slip resistance standards to best meet marketplace needs and minimize redundancy.

Keith Vidal, P.E. was invited to discuss the current status of the proposed ANSI A1264.2 Standard to the Focus Group. The Committee on Standards has not taken official action as a result of the April meeting, but they certainly became aware of the level of displeasure, distrust and disdain harbored by the various ASTM committees. The log jam that has been ongoing for many years at ASTM has prompted other organizations to continue forth in this area of standards development: one of which is the American National Standards Institute.