Playground Surface Impact Testing Expert Overview

Evaluating whether the type of surfacing material and the head impact attenuation of those fall surfacing materials were adequately safe for the height and type of playground equipment used is pertinent to child safety and injury related litigation. The premises safety and supervision experts at Robson Forensic are frequently retained in playground injury cases.

As there are many types of safety surfacing materials under and around play equipment, Robson Forensic provides access to validated, state-of-the-art equipment and laboratory facilities in which to gather data from playground environments. This includes the TRIAX TOUCH E-Missile playground surface impact testing device.

Expert Playground Surface Impact Testing Using TRIAX Touch

TRIAX Touch Surface Impact Testing in Playground Safety Investigations

Playground injury forensic investigations often require a comprehensive assessment of the play environments. The play environment includes supervision of the children, the age appropriateness of the equipment, the condition of the play equipment, and the maintenance of the safety surfacing material under and around that equipment.

The TRIAX TOUCH E-Missile:

…is fully compliant with American (ASTM F1292), European (EN 1177), and many other worldwide standards for the measurement of shock (G) and head injury criteria (HIC) values as would be experienced during an impact of a head-on a surface system.

Safety surfacing material under and around play equipment can be a loose fill product, such as engineered wood fiber, sand, etc. or a unitary system such as rubber tiles or poured in place material.

  • Unitary surfacing systems can show visible wear, especially when the product is exposed to weather and environmental conditions, but it is often difficult to ascertain using quantifiable methods whether it meets the threshold for safety if a child should fall from a specific height onto it. 
  • Loose fill safety surfacing can be measured for impact attenuation by its depth and its condition in relationship to the fall height of the equipment from which a child fell. However, it can decompose and compact in a manner that creates a hard surface with minimal impact attenuation qualities. 

Injuries caused by impact to the safety surfacing under and around play equipment are often evaluated by Robson Forensic experts. Using measurable data to assess the integrity of the safety surfacing can assist in these evaluations.

TRIAX Touch E-Missile Monitor - Expert Demonstration

Forensic Playground Safety Experts calibrating the TRIAX Touch before testing

Expert Witness Demonstration - Preparing to Test Playground Surface

The TRIAX Tripod enables experts to obtain measurements that are both accurate and repeatable from configured fall heights of up to 12 feet. The equipment is calibrated before every use by experts who have been certified as TRIAXTouch Surface Impact Testers. 



ASTM F1292 establishes minimum performance requirements for the impact attenuation of playground surfacing materials installed within use zones of playground equipment. 

In order to determine the impact attenuation of surfacing material we look at the contact caused by a moving object (impact test missile) striking another object (safety surfacing) during which one or both objects are subject to speed.  

Utilization of the TRIAX allows experts to measure the G Max (gravity) or the acceleration of the missile as it makes contact with the surfacing, and the HIC (Head Injury Criterion) which measures acceleration time history of the impact.

This combined data provides Robson Forensic experts with valuable information that quantifies the impact attenuation performance of the surfacing material in question. 

Playground Injury Expert Investigations

The experts at Robson Forensic have investigated hundreds of playground incidents. Robson Forensic provides expertise in all aspects of parks and playgrounds, ranging from design and construction, to maintenance of the equipment and grounds, to the special event programming, including supervision, hiring practices, training, and emergency preparedness.

For more information, submit an inquiry or call 800.813.6736.

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