Categories: Indoor Environment, Processes and Tools, Case Studies Sectors: Builders
A project launched last year in Victoria is aiming to slash water use by fire sprinkler systems during testing and other maintenance activities.
The project’s goal is to save 450 million litres of drinking water per year, or about 90 percent of the estimated current consumption – without any compromise in fire protection.
The first phase of the project included evaluating fire sprinkler water-saving options at 15 case study sites. The case studies ranged from high rise CBD office buildings to suburban shopping centres and large manufacturing sites.
The water consumption findings and water-saving recommendations developed through the case studies have been compiled into a 120-page guide to fire sprinkler system water saving, available through the Victorian Plumbing Industry Commission website (see PlumbSmarter, www.pic.vic.gov.au) fire sprinklers water conservation project. The guide is intended for use by the fire services maintenance industry as well as by property owners and facility managers.
The water-saving recommendations largely focus on measures for existing versus new buildings, because the major potential for water saving lies with existing building stock. Specifically, the project is targeting large, pump-boosted fire sprinkler systems that are supplied from town mains and do not incorporate recirculation tanks.
The guide identifies seven main options for cutting water consumption through testing and other maintenance of fire sprinkler systems:
- pressure settings adjustment projects;
- adoption of Australian Standard 1851-2005 and monthly testing;
- pressure-reducing projects;
- recirculation of fire sprinkler water;
- recycling (capture and further use) of fire sprinkler water;
- better zoning of fire sprinkler installations; and
- better management of fire sprinkler draindowns and recharging.
The next phase of the project will focus on promoting adoption of the first two options:
pressure settings adjustment projects and monthly testing within the framework of an AS1851-2005 maintenance regime.
Pressure settings adjustment projects
Pressure setting adjustment (PSA) projects typically include:
■ increasing the pressure relief valve operating pressure to reduce the amount of water discharging to drain during testing;
■ increasing pressure-reducing relief valve pressure in diesel pump raw water heat exchanger lines to reduce the flow of cooling water to drain;
■ in multi-pump installations, adjusting pump start pressure switches to ensure multiple pumps do not operate simultaneously during testing; and
■ provision of a pressure gauge schedule.
Proper adjustment of pressure settings can be regarded as simply good practice for fire sprinkler system maintenance, however the projects, particularly the pressure setting analysis requirements, require expertise and time beyond the
scope of everyday fire sprinkler testing.
The projects are likely to entail an additional charge by the site’s fire system maintenance firm and/ or a fire services engineering firm, but PSA projects are low cost – $2000 to $4000 – and will produce large water savings.
Consequently, the fire sprinklers initiative will now be focusing much of its efforts on gaining uptake of these types of projects. In partnership with the Water Services Association Australia (which represents urban water authorities countrywide), the project team is pursuing a funding proposal aimed at assisting uptake through industry workforce training, government-supported specialist engineering assistance and a broad industry education effort.
PSA projects will be a good option to cut fire sprinkler water consumption nationally as well as in Victoria.
AS1851-2005 and monthly testing
If a PSA project is not pursued or is unable to produce sufficient water saving at a site, a major cut in consumption can frequently be obtained by switching to the latest fire sprinklers maintenance Standard AS1851-2005, and taking up the option of monthly testing within the framework of this maintenance regime.
This alternative AS1851-2005 approach is expected to cut weekly-testing consumption by 75 percent and total periodic testing consumption by over 50 percent at most large fire sprinkler installations.
In addition to water savings, adopting AS1851- 2005 will introduce a more rigorous, comprehensive and cohesive maintenance regime for the property.
The specific advantages of AS1851-2005 compared to prior maintenance regimes include:
- more comprehensive functionality and performance testing;
- greater clarity of maintenance requirements and accountability by maintenance providers;
- annual statements of system conditions, providing clear and useful information for risk management, corporate governance, insurance and future planning; and
- greater confidence in the system operating to specification in the event of a fire.
Other options
While PSA projects and monthly testing under AS1851-2005 will have wide application and can potentially provide major water savings, solutions for fire sprinkler water conservation need to be decided on a site-by-site basis. One or more of the other five options may apply at a particular property, possibly in combination with a PSA project or monthly testing.
For example, in medium-to-large shopping centres much of the water consumption by fire sprinkler systems results from frequent draindowns, driven by constant shop fitouts and tenancy changes. For these properties, better zoning of fire sprinkler installations and/or better management of fire sprinkler draindowns and recharging may be better options for
water conservation.
Change through industry-government collaboration
The fire sprinklers water conservation project has been a genuinely collaborative industry-government
partnership approach to saving water.
The project was funded by City West Water, South East Water and Yarra Valley Water (Melbourne’s three water retailers) and the Victorian Department of Sustainability and Environment.
The Victorian Plumbing Industry Commission and the Victorian Building Commission are contributing technical, industry communications and project management support under the umbrella
of the Victorian Plumbing Industry Commission’s PlumbSmarter sustainability project.
The project working group also includes representatives from the Fire Protection Association Australia, the National Fire Industry Association, the Victorian Plumbing Division of the Communication Electrical and Plumbing Union and the Australian
Institute of Building Surveyors. Leading fire protection industry firms along with the Plumbing Trades Employees Union of Australia were the key players behind the initial impetus for the project.
More Information
Download the Guide to fire sprinkler system water saving from www.pic.vic.gov.au. Contact Haydn Wood, PlumbSmarter Project Manager, 03 9285 6438, hwood@buildingcommission.com.au
CASE STUDIES
Waverley Gardens
A pressure settings adjustment (PSA) project at Waverley Gardens, a medium-sized shopping centre, resulted in weekly-testing water consumption being cut by six million litres per year.
The PSA project required only about two days of labour time, using a combination of specialist engineering and fire service maintenance expertise. It basically consisted of expert analysis by a specialist fire services engineer and provision of a pressure schedule for the installation and careful adjustment of the pressure relief valves.
Waverley Gardens is owned and managed by Mirvac, which was keen to address the issue as part of the corporation’s strong commitment to environmental sustainability.
The centre has six major retail outlets and 116 specialty stores.
A water saving of at least one million litres per year at a cost of no more than $2000 to $4000 is expected to be typical for PSA projects.
The annual water saving will continue for the remaining life of the sprinkler installation. Assuming an average remaining life of 20 years for these types of installations, the cost of the water saving is between 10 and 20 cents
per kilolitre. PSA projects are inexpensive compared to alternative methods of water conservation and the intrinsic value of urban water resources.
QV Building
The QV building, a huge office and retail development in the heart of Melbourne’s CBD, has also decided to pursue a pressure settings adjustment project. The project is expected to cut consumption by between 1.1 and 2.2 million
litres per year. It is expected to cost about $4000 and faces no difficult regulatory hurdles.
Unlike most Victorian properties, QV is paying for the consumption of mains-supplied water for testing its fire sprinkler systems – at a cost of about $8000 per year.
Another feasible option for cutting sprinkler system water use at QV is switching from weekly to monthly testing, though this move requires adopting the latest, more rigorous Australian Standard for sprinkler maintenance (AS1851-2005) to ensure fire protection is not diminished.
Unusually for a CBD property, QV has space for a recirculation tank and this option has the highest guarantee of saving the most water, but the estimated $110,000 cost makes the payback less attractive than the other
two options. |
The article was reproduced from Fire Australia Magazine, Winter 2009 with the permission of FPA Australia. Please visit the FPA website for more information www.fpaa.com.au.
