Speedgates / Turnstiles

[Fairway123]

Hi All,

We are installing speedgates/turnstiles in one of our buildings. This is primarily as a security measure, although they will be installed in an route where we would expect some people to utilise in the event of an evacuation. The speedgates/turnstiles have retractable glass on each side (rather than a football type turnstile). We are liaising with the design team and have expressed a desire to have them fail open on alarm activation. The design team however wish to have them to go into the closed position, but on free flow - so that they can be pulled apart.

In an evacuation we feel that to have them fail in the clear open position would be beneficial so as to prevent confusion. However BS:9999 says that its OK to have them to fail in an easily openable position. There are 4000 people in the building so I think caution is needed to prevent any confusion.


Does anyone have any thoughts on their approach, if they have come across speedgates  and what kind of fail safe they used.

Thanks

[kurnal]

4000 people is a huge number. Are all exits to be fitted with speedgates? How many persons will be expected to use each exit, what is the nature of the occupancy? Will the gates remain open allowing users to tailgate each other or will they close after every person? What will trigger the gate to open? Will it be part of an exit management system / swipe card/ fingerprint scanner etc? What fail safe arrangements will be in place? How wide is the gate when open?

Sorry to ask so many questions!

[Fairway123]

Hi Kurnal,

Thanks for your questions, I've provided as much detail as I can.

Are all exits to be fitted with speedgates?  No, only those on the main entrance. The principal means of escape is via stairwells.

How many persons will be expected to use each exit, what is the nature of the occupancy? The building is classed as A1 in BS9999. The number of people who will the speedgates is probably limited to the 800, as we would expect the majority of people to leave via other exits.

Will the gates remain open allowing users to tailgate each other or will they close after every person? no they will return to the closed position.

What will trigger the gate to open? Activation of the fire alarm system.

Will it be part of an exit management system / swipe card/ fingerprint scanner etc? No, swipe cards will not be needed to egress in an emergency. Although they will be used at other times.

What fail safe arrangements will be in place? I'm not sure, all we know is that they plan to install them so they fail to loose.

How wide is the gate when open? 470mm

Thanks Kurnal :-)

[kurnal]

Sounds like they are a principal escape route, you need to show that the exit capacity is sufficient for those persons who may need or wish to use them ( total number of persons in vicinity, unaccompanied visitors etc, if a reception or search area this needs to be taken into account.) Each gate may accommodate a single stream of persons despite being narrower than standard exit widths. 800 is a lot of people though and the repeated closing after each person really slows things down. That's a bad thing. Can't you keep them open on exit in an emergency? I have often seen that done.

Interface to fire alarm should conform to BS7273-4 and incorporate an emergency release unit.

[Fairway123]

Thanks Kurnal - much appreciated.

You've actually given me a lot more information than simply this post, over the year I've been a member. I've been able to resolve many queries by reviewing previous posts on here (most of which include your thoughts), due to the high level of expertise on here. This is a really great board.

Thanks again

[Fishy]

Sounds like you might need an interface like they have on the automatic ticket gates at major railway stations - fire alarm causes them all to open and latch until the fire alarm is successfully reset (whereupon the gates can be manually reset).  They also have a manual emergency open plunger.

[Bill J]

We had a client with a similar situation.

The opening leafs of the barrier open automatically when a card is placed against the reader, however in fire condition, the mechanism "unlocks" but the blades stay where they are. So many people assuming the barriers were locked, either avoided that route, or even worse, attempted to use their card, and then stopped when the cards did not open the blades, creating a bottleneck.

Fortunately the blades are in a large manned reception, and one side gate (larger for deliveries) opens automatically. A receptionist/security guard is now charged with actually opening the blades by hand, before the upper floors reach the Ground.

It has been a while since i was there, it may have been automated now, but I know that the Building manager would have preferred a clear route. 

Bill

[Davo]

hi fairway

Are we talking staff who can be trained in their use or members of the public?
800 confused punters..............., as K says, the minutes will soon add up.
Is there room for likely queues?

davo

[Owain]

How wide is the gate when open? 470mm

Disabled access?

[Messy]

We use numerous fully enclosed security 'booths' which resemble a glass shower cubicle but are fitted with two sliding glass doors. To enter or leave, you have to step into the booth and wait for the door behind to close before the one in front opens. This prevents tailgating

All that are used for a MOE (not all are) are fitted with break glass override, are connected to the buildings UPS and have a second UPS fitted to each booth. They do not open automaticaly with the AFD but are controlled remotely/manually using fire resisting cabling and equipment with the option of the BGU override on each door.

[Fairway123]

Hi All

Thanks for contributing to the debate.

We have allocated 1 turnstile that is 1000mm wide for accessibility. I'm glad that the general consensus is that fail open turnstiles are an enhancement on fail loose. I've reported this back to the design team and await a response.

Thanks for your help.

Fairway

[Phoenix]

Hi Fairway,

I completely agree with the comments you've received so far.  Remember that exit widths are sized on the assumption that people can move freely through an open exit.  The arrangement that has been proposed to you would have a detrimental effect on flow rates and could only be deemed safe if it was clearly and convincingly demonstrated that the achievable flow rates through the turnstiles were equivalent to, or better than, the flow rate that would be achieved through a doorway that complies with the code.