Author Topic: Dry Riser location  (Read 471 times)

Offline lyledunn

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Dry Riser location
« on: January 29, 2019, 11:34:52 PM »
I wonder if you guys could clarify this; I have a 5-storey hotel 14m to top floor. BS9999 2017 requires dry riser in a non-vented lobby. Do I need this on each floor including ground? Could the riser be in the stairwell so that I can dispense with the lobby? I guess I really should break out and buy BS9990!

Offline Fishy

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Re: Dry Riser location
« Reply #1 on: February 07, 2019, 01:07:18 PM »
Wouldn't have thought so.  If the outlets are in the stair then the fire hoses will prevent the doors to the staircase closing & you'll lose the fire and smoke protection between the stair & the fire floor.

PS if the part of BS 9999  you're looking at is Table 17, it states it applies to "Any building in occupancy risk category A or B and with a height of 11 m or more, but less than 18 m".  Hotels would be occupancy characteristic C, I would have thought (Occupants who are likely to be asleep)?

Offline morph

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Re: Dry Riser location
« Reply #2 on: February 07, 2019, 02:05:31 PM »
Hello Guys, 
BS 9990 2015 specifies the below:
"A landing valve should be provided at each floor level, including the ground
floor level, where personnel can connect and fill hose lines in relative safety
before entering the fire compartment. When selecting the position of landing
valves, account should also be taken of: ease of access; exposure to fire from the
accommodation if a door is open; obstruction of fire doors by the hose line; and
the risk of unintentional discharge of water coming into contact with the lift
doors or controls.

Each landing valve should be sited:
a) within a ventilated lobby of a lobby approach stairway, where this is
provided; or
b) in a stairway enclosure; or
c) in any other position as agreed with the appropriate authority."

I believe the operational approach for using dry risers is at least 2 floors below the fire floor, hence the location in the staircase.

Another separate consideration is the use of air release valves that do not release any air.  We have experienced this locally and always have a struggle with contractors who cannot see the issues that would raise.

I am happy to discuss this privately if it would help.

Offline lyledunn

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Re: Dry Riser location
« Reply #3 on: February 08, 2019, 07:21:52 AM »
Thank you both. I should explain that I am merely handling the compliance co-ordination. We have M andE guys designing the system. It is always extremely interesting to get the operational slant, really opens the eyes!
Fishy, with respect to the requirement in Table 17, agreed it refers to occupancy A and B., but there is no reference to occupancy characteristic C for hotels.
As a matter of interest, I pointed out that our Technical Booklet E that deals with fire safety does not require dry riser provision as the building is less than 18m.

Offline Fire Monkey

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Re: Dry Riser location
« Reply #4 on: February 11, 2019, 06:15:35 PM »
I often see dry risers on every other floor (in the stairwell) and have wondered that the fire fighting crews would think if they rocked up and lets say had a fire on the 8th floor but instead of using the 6th had to use the 5th.

Any fire fighters got an operational  opinion on this?

Offline Crusher

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Re: Dry Riser location
« Reply #5 on: May 03, 2019, 08:38:46 AM »
Hi FM. I've personally only seen that set-up with maisonette type flats within high rise. Current FRS guidance is 2 floors below fire floor, so, yes it would be inconvenient if the nearest was 3 floors below. More hose, more doors to wedge, more time etc.