This European standard specifies the physical and performance requirements, methods of test, and marking requirements for industrial safety helmets for general use in industry. Industrial safety helmets are intended primarily to provide protection to the wearer against falling objects and consequential brain injury and skull fracture.
When tested by the method given in section 6.11, the maximum lateral deformation of the helmet shall not exceed 40 mm, and the residual lateral deformation shall not exceed 15 mm. The extent of damage inflicted, if any, should be noted.
The test procedure is set up using Bluehill® TestProfiler to build the ramps and dwell times required in the loading sequence profile as described below. The helmet is placed transversely between rigid parallel compression platens.
An initial force of 30 N is applied perpendicular to the platens so that the helmet is subjected to a lateral force. After 30 seconds the distance between the compression platens shall be measured (dimension x).
The force is then increased up to 430 N, which is held for 30 seconds, after which the distance between the platens shall again be measured (dimension y).
Finally, the force is decreased to 25 N and then immediately increased to 30 N, which is held for 30 seconds, after which the distance between the platens shall again be measured (dimension z).
Bluehill Expression builder is used to simply create the below custom calculations.
- The maximum lateral deformation is the difference between dimensions x and y
- The residual lateral deformation is the difference between dimensions x and z
It is suggested to use a standard Dual-Column Tabletop Frame in conjunction with compression platens.
The Bluehill® Software package is used to input specimen parameters, set the desired speed control, automatically calculate the desired results and statistics, and to produce a test report.
It is important to review EN 397 in order to fully understand the test setup, procedure, and results requirements.