Non-fragile roofs and drop tests

Posted by Admin

Non-fragile roof - Drop test

In recent years falls through fragile roofs and rooflights have been identified as one of the main causes of death or serious injury in the construction industry.

You can see our in-house non-fragile roof tests video on the right; it is part of our research and development programme.

A non fragile canopy or walkway is of particular importance in a school environment. Knowing that the school canopy is certified as non fragile and meets regulations minimises risk of a child’s injury and brings peace of mind.

Furthermore the Health and Safety Executive (HSE) is keen for all roof installations to be specified as non-fragile; especially in buildings that are considered to be at risk from vandals/intruders who find their way on to the roof. This can also be applied to fixed or freestanding canopies, school walkways and outdoor learning areas – anywhere where someone might access a building, not necessarily through the
‘proper’ entrance.

In addition the act of walking over a glazed structure could cause microscopic damage that, over time, may have a detrimental effect upon the whole system’s performance.

Legislation to be considered when designing a non fragile school canopy or walkway include:

Roofs incorporating fragile assemblies constitute a ‘fragile surface’ under Regulation 2 of the Work at Height Regulations 2005 requiring appropriate safety precautions to be taken to comply with the legal requirements of Regulation 9 (utilising work equipment selected in accordance with the hierarchy detailed in Regulation 6) of those regulations.

HSE’s Document HSG33 presents guidance on how to work safely on roofs and how to design and plan for safe working. It covers new buildings, repair, maintenance, cleaning work and demolition. It also gives guidance for those not directly involved in work on the roof, e.g. clients, designers and specifiers.

ACR [M] 001:2014 ‘Test for Non-Fragility of Profiled Sheeting Roofing Assemblies’ is a test of an assembly rather than a product. It represents a human impact incident on a roof surface, where falling through (the glazing) could result in death or serious injury.

Tests are applicable to any large element roof assembly and any accessories, which may be fitted on it, e.g. rooflights and smoke vents, and are intended to provide information about whether the particular element can support the instantaneous loads imposed by a person stumbling or falling onto it.

Pass categories than can be achieved with this test as follows:

  • Non fragile classification ‘A’ – the highest rating – is achieved only if there is no visible or significant damage to the whole assembly after multiple drops
  • Classification ‘B’ is based on minimal damage caused by multiple drops
  • Classification ‘C’ graded pass requires only one drop test with the impactor

All Kensington Systems canopies have been tested in accordance with ACR [M] 001:2014.

ACRM 001 Non Fragile Roof in our roof testing testing bay:



Non-fragile roofs and drop tests

Back to blog list