Fire Tank Inspection and Repairs
Cost effective, efficient inspection of fire tanks by divers or ROVs means you don’t have to drain the tank and your water supply isn’t disrupted.
Complying with AS1851-2012 ……Section 5
This document states that “Water storage tanks for fire protection systems” will be internally inspected annually.
Some examples of things that are covered in the inspection are:
- Internal corrosion
- Suction inlet condition
- Vortex inhibitor condition
- Roof supports
- Level indicator function
- Vermin proofing
- Tie rod condition
- Liner condition.
The standard requires the tank to be cleaned after the first year of service and then every 10 years.
Pictured below are images taken by the ROV. Left is a rusty tank column shaft and right, a half blocked internal outlet.
One method of inspection involves draining the tanks
In the past it was expected that the tank would be drained and the inspection conducted from the hatch.
To drain the tank the inspector is required to:
- Advise the owner
- Advise the Fire Brigade
- Seek temporary water supply.
Some disadvantages of this process are:
- Wasting water
- The logistics of draining the tank and 3rd party notification
- Failure of seals once the tank is drained
- The expense
- Interruption to fire water supply
- Isolation of alarms
- The environmental impact of the drained water
- The intensive labour required.
If the tank remains full it is impossible to be able to inspect all of the internal fittings and structures from an open hatch, even with a torch. There are just too many variants in tank design, structure and water quality to make this feasible.
There is another option that can be used in lieu of draining the tank
AS1851-2012 also states that; an alternative to draining the tank, “A Diver or other underwater inspection technique may be used in lieu of draining the tank”.
An effective alternative is our ROV (Remotely Operated Vehicle) for tank inspections.
Advantage of the ROV are:
- It is small enough to enter most tanks
- It flies around the tank, sending video to the surface
- It can inspect the roof and floor
- No water is used
- No alarm panels need to be isolated
- It is cost effective
- No interruption to fire water supply
- Minimal labour required
- Easy to mobilise.
Pictured below, our ROVs can access areas that may not be safe for divers to inspect.
If the tank needs cleaning or perhaps a basic leak or structural repair, the divers can be considered, if safe to do so.
The main advantages of ROVs are:
- Conservation of water
- Minimal environmental impact due to draining.
The use of ROVs and Divers as tank inspection techniques are a recent innovation so it is important that you work with experienced and qualified operators. Nordical Underwater Inspections have conducted over 2000 dive team inspections and/or cleans since 1996.
We have now added two ROVs to our inspection fleet because we recognised that due to restricted access and other safety issues, many tanks were previously unable to be inspected. Since 2010 we have conducted over 300 ROV tank inspections in VIC, NSW, SA, WA and TAS.
Find out more about working with our team on your next fire tank inspection
Call Pete on 0409 380 511 to discuss your plans or complete the online form on our Contact page.