A head start

EVERY YEAR head injuries are sustained by workers across many industries in Great Britain with devastating consequences. The latest work-related fatality figures for 2022-23 show 21% of fatal injuries were due to being struck by moving, flying or falling objects.¹

The risk of being struck in the head is extremely high in construction, forestry and heavy manufacturing. It is mandatory to wear head protection on site, but the helmet worn needs to be appropriate for the task and environment to offer protection. When equipment is selected without consideration for the varying protection levels offered by different types of helmets, workers can be at risk even while doing the right thing and wearing their hard hats. 

Industrial helmets

Industrial safety helmets meet the EN 397 standard which includes shock absorption and penetration testing to the top of the helmet. 

A 5kg hemispherical striker is dropped from 1m onto the crown, creating an impact energy of 50J, and the force transmitted to the headform must not exceed 5kN. A penetration resistance test is conducted with a 3kg conical striker dropped from 1m which must not contact the headform. 

There is no side impact test for EN 397 helmets, only a lateral rigidity test, which is a slow, progressive force loading followed by measurement of any deformation. 

Industrial helmets are often used in construction and manufacturing applications where there is a high risk of falling or ejected objects in environments without fall hazards. 

Mountaineering helmets

Mountaineering helmets meet EN 12492. This standard includes tests for top, side, front and rear shock absorption, as well as penetration resistance testing to the top of the helmet. 

Shock absorption testing is conducted with two 5kg strikers. A hemispherical striker is dropped from 2m onto the crown, creating an impact energy of 100J. A flat striker is dropped from 0.5m onto the front, rear and side of the helmet with the headform tilted to 30°, creating an impact energy of 25J. In all impact tests, the transmitted force must not exceed 10kN. 

Two penetration tests are performed within a 50mm radius of the helmet’s crown. A 3kg pointed striker is dropped from 1m and must not contact the headform. The helmet must also incorporate a retention system with non-detachable chinstrap which is tested for strength under 500N of force. 

Mountaineering helmets are often selected for work at height in construction and forestry. All-round shock absorption combined with the retention system function protect against repeated impacts from multiple directions and keep the helmet firmly on the head. 

High performance helmets

The EN 14052 high performance helmet standard includes both shock absorption and penetration testing to the top, front, rear and side of the helmet. 

Shock absorption testing is conducted with a 5kg hemispherical striker. The striker is dropped from 2m onto the crown of the helmet, creating an impact energy of 100J, and the force transmitted to the headform must not exceed 5kN. The same striker is dropped from 1m onto the front, rear and side of the helmet with the headform tilted to 60°, creating an impact energy of 50J. In these tests, the deceleration of the striker must not exceed 300g. 

Penetration testing is carried out with a 1kg blade striker. The striker is dropped from 2.5m onto the crown, and from 2m onto the side, front and rear with the headform tilted to 60°. The striker must not contact the headform and the transmitted force must be below 5kN to the crown and 15kN to the side, front and rear. 

EN 14052 helmets are used in high-risk environments such as demolition and quarrying. The heavy duty all-round shock absorption and penetration resistance protects against more intense repeated impacts from multiple directions. 

Chinstraps

Chinstraps are mandatory for mountaineering helmets, forming an integral part of the retention system, but they are optional for other helmet types. 

EN 397 and EN 14052 helmets can be fitted with a chinstrap for extra security in applications involving a high degree of activity however this is not mandatory. The requirements for optional chinstraps in both standards include tests to ensure the chinstrap anchorage releases under a force of 150-250N, allowing the helmet to be removed easily should it become caught on machinery or equipment in an industrial setting. 

Chinstraps for mountaineering helmets work differently. EN 12492 includes a test to make sure the retention system does not break or elongate under a force of 500N, for safety in the event of repeated impacts from swinging or multiple falling masses. 

Selecting a mountaineering helmet for use in an industrial environment can put the wearer at risk, making it more difficult to remove should the chinstrap become caught on something. Conversely, using an EN 397 or EN 14052 chinstrap in a work at height situation can reduce protection against multiple impacts. 

Industrial bump caps

Industrial bump caps are tested and certified to EN 812. They serve a different purpose to safety helmets and should never be selected for use where a helmet is required. While bump caps provide protection to the wearer from the effects of striking their head against stationary objects, they are not designed to absorb impact from falling masses. 

Bump caps can be suitable for certain manufacturing settings, such as automotive and food production, where there is a risk of striking the head against something stationary but falling objects do not pose a hazard. 

Whilst it is mandatory to wear head protection on all sites, helmets must be selected carefully to properly protect the wearer. Shock absorption and penetration resistance levels vary depending on a product’s intended usage. Using the wrong type of safety helmet can significantly reduce protection and potentially put the wearer at greater risk. Understanding how to select appropriate head protection for different tasks and environments is key to ensuring safety for everyone on site.

References

1 Work-related fatal injuries in Great Britain 2023, www.hse.gov.uk/statistics/pdf/fatalinjuries.pdf

Louise Charlton is technical copywriter at JSP. For more information visit www.jspsafety.com