Playgrounds can be a source of great happiness and joy for children. However, they can also be a 
source of injury. To minimize injuries from trips and falls, especially falls from equipment, playgrounds 
are being equipped with shock absorbing surfaces under and around equipment. While various materials 
provide shock protection, some of the most protective surfaces are being provided by scrap rubber derived 
materials. There have been questions or concerns raised about tire derived materials being used for 
playground cover. This Briefing Sheet is intended to provide answers to these questions. The information 
provided below is taken from a variety of sources, including State & Federal agencies, laboratories contracted 
by State agencies, research hospitals, licensed testing companies and rubber manufacturers. 

Two types of rubber playground surfacing material are on the market today: loose fill and solid mats. Loose 
fill generally consists of chips of rubber ranging from one half inch to three quarters inch in size. All non-rubber 
materials are removed, and the chips are washed before being placed on the play ground. Rubber, does not 
contain asbestos nor fiberglass as reinforcement fibers. 

Safety Value of Scrap Rubber Material as a Playground Cover: 

According to the Mayo Clinic (Mayo Health O@sis, May, 1998), about 70 percent of playground injuries are a 
result of falls. The Consumers Product Safety Commission recommends that "hard surfacing materials, such 
as asphalt or concrete, are unsuitable for use under and around playground equipment of any height unless 
they are required as a base of for a shock absorbing unitary material such as a rubber mat." (CPSC document 
1005). The CPSC defines unitary materials as "...generally rubber mats or a combination of rubber-like 
materials held in place by a binder that may be pour in place at the playground site and cures to form a 
unitary shock absorbing surface." (CPSC document 1005). 

Shock Attenuation: 

The Mayo Clinic recommendation is to use playground mating/flooring that "gives", such as rubber. The 
State of Illinois conducted a direct comparison between scrap tire rubber and other loose fill playground 
surfacing materials at a depth of six inches. It is reported that wire-free scrap tire chips have roughly twice 
the cushioning effect of other material. (Report to the Illinois Department of Commerce and Community 
Affairs, January 1994). 

Critical Heights for a 6 Inch Uncompressed Layer* 

Wood Mulch          5 feet 

Fine Sand             5 feet 

Medium Gravel     7 feet 

Rubber Chips       12 feet 

Rubber shreds/chip data from the Illinois Department of Energy & Natural Resources. Measured in 
accordance with ASTM F12-93 and ASTM F355-86. Data on other materials from U.S. Consumer 
Product Safety Commission, CPSC Document 1005. 

*According to the testing criteria, the higher the height, the safer the material. Flammability: 

Rubber chips were tested in 1995 in accordance with the Federal Hazardous Substance Act (16 CFR 1500.44) 
to determine whether this material would be considered "flammable" (a material is considered flammable 
if it ignites and burns with a self-sustained flame at a rate greater than 0.1 inches per second along its major 
axis). From the test results it was concluded that scrap rubber material is considered non-flammable. 

Other Advantages of Wire-Free Scrap Rubber Chips: 

Clean and non-toxic 

Does not produce toxic leachate 

Resilient 

Does not attract or maintain moisture   

Economical, lasts for years 

Reduces dust and mud around playing area 

Does not attract cats, dogs, rodents or insects 

Will not rot or decay 

Not susceptible to reduced performance due to rainy weather or freezing temperatures 

What if a Child Swallows a Rubber Chip? 

In 1994 the Maryland Environmental Services (MES) put this question to a series of tests. At the MES 
request, a testing laboratory subjected 3/4 inch pieces of rubber chips to hydrochloric acid (stomach 
acid). "Visual examination of insoluble residue appeared to indicate only fibrous reinforcing strands 
were dissolved by the hydrochloric acid. The tire rubber did not appear to be affected in any way; i.e. 
chalking, cracking, spauling, fracturing, etc." (PSI report No. 486-40013-001). What does this mean? If a
 piece of rubber is swallowed, it should not cause any acute or chronic problems. Short-term issues, 
such as an upset stomach will be a function of the amount of rubber swallowed. As to the fate of the 
rubber chips swallowed, they are eventually evacuated from the body, just like any other non-digestible 
material. 

Additional Information: 

For further information on playground safety, contact the Consumers Product Safety Commission, 
Washington. DC 20207; http://www.cpsc.gov. We suggest obtaining their publication on Playground 
Surfacing Materials, CPSC Document #1005. The STMC is not-for-profit, advocacy organization, founded 
and supported by the United States based rubber manufacturers. The Council is part of the Rubber 
Manufacturers Association, the trade association representing the United States rubber industry. 
The Council’s primary function is to assist in the promotion and development of environmental sound 
and cost efficient markets for the scrap rubber generated in the United States. 

Playground Installation Specifications

Proper Playground Equipment Placement

The use zone for each piece of equipment is made up of two parts:

	The Fall Zone: an area under and around the equipment where protective surfacing is required, and,
	The No-Encroachment Zone: an additional area beyond the fall zone where children using the equipment can be expected to move about and should have no encroaching obstacles.

With the exception of spring rocking equipment, equipment under 24 inches in height, and the zone between adjacent swings (see below), the fall zones of adjacent pieces of equipment should not overlap. However, adjacent pieces of equipment may share a single no-encroachment zone.

Regardless of the type of equipment, the use zone should be free of obstacles that children could run into or fall on top of and thus be injured. For example, there should not be any vertical posts or other objects protruding from the ground onto which a child may fall.

Recommendations for Fall Zone

Stationary Equipment

The fall zone should extend a minimum of 6 feet in all directions from the perimeter of the equipment.

Slides

The fall zone in front of the access and to the sides of a slide shall extend a minimum of 6 feet from the perimeter of the equipment. Note: This does not apply to embankment slides.

The fall zone in front of the exit of a slide shall extend a minimum distance of 6 feet from the end of the slide chute or for a distance of H + 4 feet whichever is the greater. H is the height of the slide platform and the H + 4 foot measurement is made from a point on the slide chute where the gradient has been reduced to 5o from the horizontal (see Figure 16).


Shaded Area Denotes Fall Zone with Protective Surfacing


Figure 16 Fall Zone for Slides

Single Axis Swings

Because children may deliberately attempt to exit from a single axis swing while it is in motion, the fall zone in front of and behind the swing should be greater than to the sides of such a swing. It is recommended that the fall zone extend to the front and rear of a single axis swing a minimum distance of 2 times the height of the pivot point above the surfacing material measured from a point directly beneath the pivot on the supporting structure (see Figure 17). The fall zone to the sides of a single axis swing should follow the general recommendation and extend a minimum of 6 feet from the perimeter of the swing structure in accordance with the general recommendation for fall zones. This 6 foot zone may overlap that of an adjacent swing structure.


Shaded Area Denotes Fall Zone with Protective Surfacing


Figure 17 Fall Zone for Single Axis Swings

Multi Axis Swings

The fall zone should extend in any direction from a point directly beneath the pivot point for a minimum distance of 6 feet + the length of the suspending members (see Figure 18). In addition, the fall zone shall extend a minimum of 6 feet from the perimeter of the supporting structure. This 6 foot zone may overlap that of an adjacent swing structure.

Merry-Go-Rounds

The fall zone should extend 6 feet beyond the perimeter of the platform.

Spring Rocking Equipment

The fall zone should extend a minimum of 6 feet from the "at rest" perimeter of the equipment but adjacent spring rockers with a maximum seat height of 24 inches may share the same fall zone.

Composite Equipment

The above recommendations for individual pieces of equipment should be used as a guide in establishing the fall zones around pieces of composite playground equipment. Note that in Section 9.2.2 it was recommended that single axis swings not be a part of a composite structure.


Shaded Area Denotes Fall Zone with Protective


Figure 18 Fall Zone for Multi Axis Tire Swings

Recommendations for No-Encroachment Zone

No specific dimensions can be recommended for the noencroachment zone around individual pieces of playground equipment. These dimensions will vary according to the types of adjacent pieces of equipment and their orientation with respect to one another.

For example, the recommended fall zone at the side of both a slide and a swing is 6 feet. Since fall zones should not overlap (with the exception of certain adjacent spring rockers), a slide could be placed with its side no closer than 12 feet to the side of a swing. Therefore, there may be no need to add an additional no-encroachment zone. Conversely, it would not be desirable to have a slide exit facing the front or rear of single axis swing.

No-encroachment zones extending beyond the fall zones are recommended for moving equipment or equipment from which the child is in motion as he or she exits. This allows more space for children to regain their balance upon exiting the equipment and also provides added protection against other children running into a moving part.

For a single axis swing, it is recommended that there be a barrier beyond the fall zone in front of the swing if it is located in a playground facing other pieces of equipment.

Information Source:

http://www.cpsc.gov/cpscpub/pubs/327.html visit the CPSC site at this link for more information.

This article is a excerpt from the "Handbook for Public Playground Safety", Pub. No. 325
U.S. Consumer Product Safety Commission, Washington, DC 20207.