Standards Development

Scope

This document is designed to provide information to convenors that will help in choosing test limits in relation to a particular injury type and severity. It is worth noting that accident investigators use a scale known as the Abbreviated Injury Scale, AIS (AAAM). This was developed (in the USA) so that injury severity could be recorded in databases regardless of the body region and type of injury thus avoiding lengthy medical terms that were unfamiliar and difficult to interpret.

This document begins by reviewing the AIS scale and its application to head and burn injuries. Thereafter, each measurement type is reviewed and the severity of injury for given values is identified where possible. A section on burn injuries and fatigue related to heat exposure has been included to assist with Standards for equipment to protect firefighters. The Appendix describes the skin structure and the category and consequence of burn injuries.

Purpose

Members of helmet Standards committees frequently need to define limits for test procedures. Such limits relate to test values that indicate the potential for injury and yet it is often difficult for members to know the type and severity of injury that is represented by a given test value. Unfortunately, the data for such an analysis is generally difficult to obtain because measurements generated by test apparatus do not relate directly to injury severity because a headform for example does not respond in an impact like a human head. Hence, it is necessary to find a relationship between these test measurements and injury severity. This report shall include and try to describe the injury metrics related to the most common test methods in the European helmet standards.

Significant changes proposed:

− Using the obligatory CEN simple template,

− added clauses for a Scope and Terms and definitions

− added Table with test methods and metrics correlated to different injury risks

− Updated Table 2 AIS scale with head injury severity

− Differentiating between linear and rotational shock absorption

− Updated metrics for linear shock absorption

− Added metrics for rotational shock absorption

− Peak rotational acceleration and velocity, BrIC and Combined injury metrics

− Added Force transmission

− Removed Neck injury as it is not within the scope of head protection

− Removed Noise injury as it is not within the scope of head protection

− Updated Annex A