Backflow Special Interest Group Christchurch Christchurch 24 September 2008

Backflow Prevention Practised by a few Understood by some Misunderstood by many Ignored by thousands!

The Great Divide Backflow requirements of the Water Supply Authority. Backflow requirements of the Water Supply Authority. Backflow requirements under the Building Code. Backflow requirements under the Building Code.

Supply Authority v Building Code requirements A device at every boundary. A device at every boundary. An appropriate device installed at every identified source of a potential hazard. An appropriate device installed at every identified source of a potential hazard. Issue is the reconciliation of conflicting requirements. Issue is the reconciliation of conflicting requirements.

Building Consents Building Consents Standardisation of requirements Standardisation of requirements Acceptable Solution Acceptable Solution Verification Method Verification Method Alternative Solution Alternative Solution Adopt AS/NZS Water Services, in total?? Adopt AS/NZS Water Services, in total??

Building Consents Building Consents Who is confused????????? Who is confused????????? The average tradesman wants a simple list of what to put where! The average tradesman wants a simple list of what to put where! Proactive to produce an “Advisory Note” for the use of all the industry. Proactive to produce an “Advisory Note” for the use of all the industry. Adopt AS/NZS in total?? Adopt AS/NZS in total??

Building Consents Building Consents What about Devices not part of a Building/Compliance schedule: What about Devices not part of a Building/Compliance schedule: Pumping stations, Pumping stations, Sports grounds, Sports grounds, Parks and gardens, Parks and gardens, Water truck mounted devices, Water truck mounted devices, Marina’s? Marina’s? Boundary devices – who registers these and records that they are tested? Boundary devices – who registers these and records that they are tested?

Compliance Schedules Proactive audits on buildings that are late submitting their Warrant of Fitness? Proactive audits on buildings that are late submitting their Warrant of Fitness? Carry out a Cross Connection survey during inspection? Carry out a Cross Connection survey during inspection? Acceptance of disclaimers on Form 12A? Acceptance of disclaimers on Form 12A? Better to receive some documentation from an IQP than none at all!!

Domestic Fire Sprinklers A correctly designed “Combination” domestic fire sprinkler systems is not a backflow hazard. The specific intent of a “Combination” system is to have a domestic fixture connected to the sprinkler line, drawing-off water every time that fixture is used. The sprinkler system and the domestic water system are thus one “Combined” system. Please review a typical layout of a “Combination” system

M Sprinkler 1 Sprinkler 2 Sprinkler 3 Sprinkler 4 Sprinkler 5 Sprinkler 7 Sprinkler 8 Sprinkler 9 Sprinkler 6 Domestic Supply 1 15 CU Pipe drop in Wall. 12 l/m 40 CU Pipe rise 4.0 m in Wall l/m Pipe Loop in ceiling space Pipe in trench. 140 m Mains Tap-in & Ferrule Water meter and dual check Typical “Combination” Domestic Fire Sprinkler System (NTS) A B C D E F Change pipe material at “D” 32 CU m 40 CU 50 MDPE 32 CU m l/m l/m Pipe Loop in ceiling space 25 CU m 25 CU = Most Hydraulically Disadvantaged Sprinklers = Less Hydraulically Disadvantaged Sprinklers 32 CU m 32 CU m Length of pipe section “E” to “F” is 4.0 m NB. Sprinkler 8 & 9 are in the same room 3.5 m Any number of domestic take-offs are permitted

Domestic Fire Sprinklers No backflow hazard exists in a correctly designed “Combination” domestic fire sprinkler system. FIRE SPRINKELR SYSTEMS SAVE LIVES. MAYBE YOUR LIFE! Embrace the concept of “Combination” domestic fire sprinkler systems. They do not use “more water” as has been stated!!

Domestic Fire Sprinklers A “statement” endorsing the concept:- “that correctly designed COMBINATION domestic fire sprinkler systems pose no backflow hazard” would be helpful in providing guidance to Designers, Territorial Authorities, Installers, NZ Fire Service and Consumers.

Challenges Education of the trade, Education of the trade, Education of the general public, Education of the general public, All the practitioners of the dark art of backflow prevention TALK to each other. All the practitioners of the dark art of backflow prevention TALK to each other. Imported products? Imported products? Dispensing faucet, water, soap and lotion. Steam ovens – testable double check?

Questions?

Thank You End Presentation