Protection for Underground Distribution Boxes

Protection for Underground Distribution Boxes

BLASTGUARD mitigates against the effect of Underground Distribution Box (UDB) failures by safely absorbing and dispersing the kinetic energy, while protecting against the heat energy from an explosive failure.

No need to replace lid, air vents not required.


The number of disruptive UDB failures reported has increased over the last number of years. There is evidence that many fail due to ingress of water, and the presence of gas can make the impact of such failures worse. Incidents of Linxbox explosions have resulted in the cast-iron cover being blasted 3 metres into the air, with the heavy bell housing not far behind.



Testing and research has shown that the use of blast mitigation materials dramatically reduces the impact of UDB explosions, even in the presence of explosive materials such as gas. This has resulted in the KELVATEK BLASTGUARD device, a bag of blast mitigation materials that absorb most of the energy of a UDB explosion, and supress the flames as well.



Demonstration tests show that a blast mitigation bag can reduce the height of vertical travel of the cover from over 3 metres to less than 60cm. The kinetic energy, and the risk to the public is greatly reduced with BLASTGUARD.

KELVATEK manufacture a number of different sizes of BLASTGUARD, catering for different sizes and types of linkbox.


A BLASTGUARD bag is easily retrofitted into the manhole, under the cover, and above the bell.

To reduce risk, protect people and buildings and to invest more wisely.