What is it:
A dry riser is an empty pipe that can be externally connected to a pressurized water source by firefighters.
It is a vertical pipe intended to distribute water to multiple levels of a building or structure. It has outlets on each level of the building for firefighters to connect their hose to.
Why is it needed:
Building Regulations: Approved Document B (fire safety) requires that any building more than 18m high, measured from the fire brigade access level to the top floor, or which has floors more than 10m below ground must be provided with ‘fire fighting shafts’ and a fire fighting rising main. This can be a wet or dry riser.
Most buildings have a "wet riser" system where the pipes are kept full of water for manual or automatic fire fighting operations. Dry risers are used when the water pressure of a building wouldn't be enough for fire suppression, and in unheated buildings where the pipes could freeze. Dry risers have to allow access to a fire engine within 18 m of the dry riser inlet box. Dry risers in occupied buildings have to be within a fire-resistant shaft, usually one of a building's fire escape staircase enclosures.
Dry risers include an inlet which is an external access point at ground level through which water can be pumped from the fire department's fire engine pump to firefighters' fire hose attachments on each floor.
Dry risers must be serviced and maintained annually. They’re flow rate is tested, pressure tested at the highest valve point. Their valves are checked for damaged seals and various other important checks are carried out including the air release valve at the top of the riser.
Laying a firehose up a stairwell takes time, and this time is saved by having fixed hose outlets already in place. There is also a tendency for heavy wet hoses to slide downward when placed on an incline (such as the incline seen in a stairwell), whereas dry risers do not move. The use of dry risers keeps stairwells clear and is safer for exiting occupants. Dry risers go in a direct up and down direction rather than looping around the stairwell, greatly reducing the length and thus the loss of water pressure due to friction loss. Additionally, standpipes are rigid and do not kink, which can occur when a firehose is improperly laid on a stairwell.
Wet & Dry Riser quote:
If you would like to have a quote for either a Wet Riser or a Dry Riser please contact us via the contact page here, or you could call us or email us with the details on the contact page.
Kwa mfano, riser kavu ni bomba tupu ambayo inaweza kushikamana na chanzo cha maji ya shinikizo. Ni bomba wima lengo la kusambaza maji kwa ngazi nyingi za jengo au muundo. Ina viunganishi katika kila ngazi ya jengo kwa ajili ya wazima-moto kuunganisha bomba lao. "Hii ni kwa sababu ya kanuni ya ujenzi iliyoidhinishwa na B (Usalama wa Moto) inahitaji kwamba jengo lolote lenye urefu wa zaidi ya mita 18 (iliyopimwa kutoka kwa kiwango cha upatikanaji wa vikosi vya moto hadi ghorofa ya juu) au ambalo lina ghorofa zaidi ya mita 10 chini ya ardhi lazima liwe na ""shati za kuzima moto"" na rising main ya kuzima moto." Hii inaweza kuwa mvua au kavu riser. Majengo mengi yana mfumo wa "kuinua mvua" ambapo mabomba huhifadhiwa yamejaa maji kwa ajili ya shughuli za moto za mikono au za moja kwa moja. Dry risers hutumiwa wakati shinikizo la maji la jengo halitakuwa la kutosha kwa kuzima moto, na katika majengo yasiyo na joto ambapo mabomba yanaweza kufungia. Kwa hivyo, risers kavu lazima ziwe na uwezo wa kufikia gari la moto ndani ya mita 18 kutoka kwa sanduku la kuingia la riser kavu. Kwa hivyo, risers kavu katika majengo yanayotumiwa lazima iwe ndani ya shaft ya moto, kwa kawaida moja ya maghala ya ngazi ya kutoroka moto ya jengo. Dry risers ni sehemu ya nje ya ardhi ambayo inaweza kuingiza maji kutoka kwa bomba la moto la idara ya moto hadi kwenye viunganishi vya bomba la moto kwenye kila ghorofa. Vipuli vya kupasha maji vinapaswa kutunzwa na kudumishwa kila mwaka. Wao ni kiwango cha mtiririko ni majaribio, shinikizo majaribio katika hatua ya juu ya valve. Valves yao ni kuchunguzwa kwa ajili ya seals kuharibiwa na mbalimbali nyingine muhimu ukaguzi ni kufanyika ikiwa ni pamoja na hewa kutolewa valve juu ya riser. Kuweka bomba la moto kwenye ngazi huchukua wakati, na wakati huo huokolewa kwa kuwa na vijia vya bomba vilivyowekwa tayari. Pia kuna mwelekeo wa mabomba mazito ya mvua kuteleza chini wakati wa kuwekwa kwenye mteremko (kama vile mteremko unaoonekana katika ngazi), wakati risers kavu hazihamishi. Matumizi ya risers kavu anaweka stairwells wazi na ni salama zaidi kwa kuondoka abiria. Dry risers kwenda moja kwa moja juu na chini badala ya looping kuzunguka stairwell, sana kupunguza urefu na hivyo hasara ya shinikizo la maji kutokana na hasara friction. Kwa kuongezea, mabomba ya kusimama ni magumu na hayapinduki, jambo linaloweza kutokea wakati mfereji wa moto unapowekwa vibaya kwenye ngazi. Kwa mfano, ikiwa unataka kupata nukuu ya Riser ya mvua au Riser kavu, tafadhali wasiliana nasi kupitia ukurasa wa mawasiliano hapa, au unaweza kutupigia simu au kutupelekea barua pepe na maelezo kwenye ukurasa wa mawasiliano.