Compliance and testing - Blast
According to the technical report produced by TPS, BBX walls demonstrated “additional reserves of capacity”.
“BBX is able to compete with heavier blocks whilst providing comparable levels of protection,” says TPS.
TPS added "When compared to ordinary CMUs, BBX has the advantage of vastly increased shear modulus and improved tensile capacity."
Blast pressure results
The table below summarises the blast pressures and impulses withstood by BBX walls against a charge the size of a car bomb at different standoff distances and for a range of BBX walls thicknesses.
|BBX wall depth (mm)||Best stand off distance (m)||Verified EXV load classification|
Home Office protection categories
This table shows that all the walls exceeded the Home Office standards for C25 and C15 for explosive resistant walls and doors, whilst obtaining a hazard rating of B against a VBIED.
A hazard rating of A-C means that the surface of the wall after the blast did not spall.
In real terms this means protection of employees and equipment. Standard CMU blocks cannot offer these levels of protection.
|BBX wall thickness (mm)||Home office protection category||Hazard rating||Home office standard for explosive resistant walls and doors|
|100||C25 (EXV19)||No hazard B||Y|
|215||C15 (EXV12)||No hazard B||Y|