Means of escape - spiral staircase and high risk area

[Fire Monkey]

Morning all,

I have visited (on other business - not an  fire risk assessment) a (non sleeping) building recently that has a poroteted main staircase, a spiral staircase, and a 2nd staircase that leads to a garage/loading bay (which is used to storage all kinds of fire risks - batteries, heat guns and electrical charging equipment, flammables and so on). Taking into account travel distances, the fact the the occupants are familuar with the building, the amount of early warning, compartmenalisation and occupant training, can there be every a case for making use of this garage as a means of escape? I ask becasue there is a protected stair case and a spriral staircase (that leads directly to a fire exit door) as alternative (is there ever a case for making use of a protected spiral starcase a means of escape, for able bodied people) - so there are aways aleternative routes. I wonder if such an environment (the garage) would be concidered a meduim risk or a high risk (like a commercial kitchen), which would clearly affect if it could be used as a fire exit route.

I can email a plan should any one be interested in having a look.

Thought/comments on a post card - your sage advise would be most welcome.

[JT]

What numbers are you looking at?

Are there 3 separate means of escape? Spiral, garage and normal staircase.

[Fire Monkey]

There are about 40 desks - with average occupation lelvels. No public visitors.Yes - a seperate means of escape from each staircase.

[JT]

As long as the 3 routes are separated by fire resisting construction it sounds fine. Even if one of the routes was classed as high risk, it's separate from the other two.
Extract from the clg guides:
Spiral and helical stairways are usually acceptable only in exceptional situations, e.g. for a maximum of 50 people who are not members of the public. The stairway should not be more than 9m in total height and not less than 1.5m in diameter with adequate headroom. A handrail should be continuous throughout the full length of the stairway.
However, spiral and helical stairways may be used as means of escape by more than 50 staff and may be used by the public if the stairways have been designed for that purpose. Further guidance is given in BS 5395-2,26 including about type E (public) stairs under that standard.

Hope that helps.