Hi Messy

recently rewrote a strategy in a central London building, again thousands of staff, multiple governmental departments each on two of the eight floors above ground. Sweep system. Fire evac was default through the front door with assembly outside the front of the building(unless the fire was there of course). In the event of a bomb evac, exit route was down to the basement, into the underground car park(high level of protection - thick concrete roof - where they seperated by different organisation, so that each member of each organisation knew where their assembly point was situated.

Sweep system was the same, and out of hours, individuals were responsible for signing in with security, and signing out when they left. The alarm system posed a problem - due to the fact that the fire alarm sounding caused staff normally to go to their normal fire assembly point, the local police and LFB wanted a seperate tone which was different from go the fire alarm tones, to ensure that people did not go to the wrong assembly point. There was a spoken element to the alarm which due to the age of the system could not be amended, so it was decided that security controller would give a spoken instruction that the building was to be evacuated, and that assembly point B would be the one used.

Not ideal. But landlord would not pay for a new system.

“But what about a bomb evacuation? It's not feasible/safe to the volunteer delay fire warden's to send them into potentially a high risk area to sweep and confirm it's clear of staff
So what do you do to ensure the building is totally evacuated”

Messy, Unless military or political target, it would be normal for said terrorist to attempt to provide for evacuation of civilian’s from the premises prior to detonation. However and of course mistakes can and do occur.

IMO, it is not a case of sending wardens back into the building or having them carry out a protracted sweep beyond the time expected for general evacuation of the populace in question. I would anticipate a very short period of delay in respect of wardens following immediately behind the evacuating staff from the building. This is as much as may be expected and can only be considered as an action carried out in so far as is reasonably practicable. IMO, verification of persons reported post evacuation, is then down to the emergency services.

Selection of emergency escape, place of safety and stand-off distance is down to the emergency preparedness of the organisation in question. It is not easy to predict the planting of explosive devices on normal access/egress routes versus alternative means of escape or indeed car parking locations. As you are well aware, that is where demonstrable competence should be considered by the organisation in question.

Typically and in my experience, explosive ordinance of a size to cause substantial damage, is restricted to goods received or car parking/load bay areas, unless security is lax to the degree that brief case sized packages can be introduced to site. Bio or incendiary threats on the other hand, can be delivered to specific desk/personnel or office locations.

messy

I have lived and worked in Belfast for half a century and every one of my employers needed to develop suitable evac procedures for bomb alerts, especially the case in my 18 years in the power industry where every asset was a target.

I worked closely with all the emergency services and there advise was to use your existing process, in our case sweep, to clear the building as it was a tried and tested and effective existing process. They advised against adding unnecessary new process. In all the drills and the THREE occasions when we actually had alerts, with one being the real thing (300kg bomb in small van) the process worked fine.

One piece of advice was to consider a bomb outside of the building, easiest place to put it, the risk was then of evacuating people into an unknown area of risk. Advice was to keep people in the building but away from areas of glazing etc, best place was in any protected staircase.

But Bob's advice is key, never ever go looking for a suspect device, they don't want to be found!