Blast testing Security Devices visors in Angola 1997
Extracts from a report made to the Sir Halley Stewart Trust, UK, who funded the "technology transfer" of visor manufacture to SD in Zimbabwe. These record the first tests of SD visors, and were immediately followed by other tests in Mozambique (also in 1997) when NPA hosted confirmation trials. Remarkably, the visor withstood the detonation of a POMZ-2 at two metres during the Mozambique tests, but we acknowledge that this was luck and would not have sanctioned such a severe test ourselves. No record of the Mozambique test survives, although retired Brigadier John Hooper (resident in Monmouth, UK) has recently confirmed that they were entirely succesful.
Blast test 1:
MgM with their EOD man John Kirby. A Rumanian MAI 75 AP mine was fitted with a det cord through that was curled and knotted - supposedly to mimic the blast direction of the original detonation. Excess PE was used. The visor was mounted at approximately 65cm and 30 degrees from vertical (mimicking the position of a local kneeling deminer when probing. I got one of the deminers to use the video: he recorded everything up to the blast but turned off the camera for the 3,2,1 countdown. Hey, I don’t speak Portuguese so how was I to communicate? I took still photographs before and after. The visor survived with only light damage - the cleaner here, bless her desire to get into my wallet, cleaned the visor vigorously so that it could be worn again. John Kirby gave the visor his seal of approval and considered the test conclusive.
Blast test 2:
A test carried out by two UN men who like making blasts at the INAROEE demining school just outside Luanda. In the absence of the right amount of UN paperwork (or the time to get it), I was not allowed to be present. They took Polaroid’s before and after. I must not name them in any report. It took three attempts for them to get a reasonable blast (using live mines). In the end they used a MAI 75 with a PE detonation charge and tied a used LBA visor opposite an SD visor on sticks. From the photos they seem to be more like 75cm from the blast than the 60cm I asked for. They were about 30 degrees away from vertical as requested. After initiation the LBA visor’s head-frame had broken in several places: our head-frame was undamaged. Fragment strikes on the visor faces were fairly even, with about 10% more on the SD visor, which was also more sooted. Both took the blast without fracture but with significant pitting, so I consider that it was a fair test. The UN men said that they thought our visor was the better. They tapped the polycarbonate and said that the SD material sounded firmer (it is not brittle as the fragment strikes near the top demonstrate). They thought that the SD visor would provide better protection against AP mine blasts. I think this unlikely and told them about the difference in manufacture. The difference in sound is genuine and may be because the older visor has suffered some UV degradation. Another “seal of approval”.
Blast test 3:
Mark Buswell, NPA and Sheilagh (SP) the Kiwi “commandant” of NPA purchasing agreed to test a visor. They insisted on doing it their way regardless of what I might say about trying to limit variables. The result was reported to be “good” with the visor undamaged but I was not allowed to be present and no photographs were given despite repeated requests. God the arrogance in demining is profound! Nonetheless, I count this as another success.
The ultimate "blast-test"
is the performance in real accidents
The results of demining accidents recorded in the DDAS show that Security Devices products perform at least as well as all other in real explosive events. Our visors have been involved in well over 100 real accidents and they have always performed at least as well as other brands (and demonstrably better than some).
See a previously unpublished extract of a report submitted to US ARMY CECOM NVESD in 2000 covering blast testing some of our hand-tools in detail. This PDF file includes many photographs. We believe that it should be compulsory reading for anyone doubting the need for blast resistant tools.
A previously unpublished PDF extract of a report submitted to US ARMY CECOM NVESD in 2000 covering those user and blast tests. The equipment was liked by the deminers and performed very well against PMN mines with loose stones on top.
SADEC conducted independent tests in Zimbabwe, Mozambique and Namibia during 2001. They successfully tested a range of equipment, including SD body armour and visors. See an extract from the report on that testing.