Enhancing Interpretability of Data-Driven Fault Detection and Diagnosis Methodology with Maintainability Rules in Smart Building Management

Table 9

Plumbing & Sanitary Systems - Water Tank.

Problem	Design	Construction	Maintenance
Unauthorised/poor accessibility; Lack of safety cover and security lock in water tank; Good practice; make provisions for access to water tank(s) for maintenance and/or inspection	Provide a permanent climbing ladder for easy inspection and cleaning of interior. If the ladder rises a vertical distance of more than three metres, then additional fall prevention measures should be considered such as install a safety cage [12, 13]. Provide a minimum of 600 mm space, all around the sides of the tank with at least 1.2 m space from the top of the tank to the ceiling for maintenance, repair and inspection purposes. Install minimum possible number of openings to each compartment; each opening should be fitted with a cover/trapdoor. Sanitary pipes should not be placed above potable water storage tank. Backwash water from swimming pool filter system backwash holding tank should be discharged into a sewerage system.; Provide corrosion- resistant, mosquito-proof netting for overflow pipe/vent.; Design a series of tanks instead of one large tank, to meet demand for isolation during maintenance, for ease of access.	Ensure there is adequate access space to and around the tank. Edge protection e.g., guardrail should be provided to prevent personnel from falling from open sides of the tank [12, 13].; Ensure that the tanks are not compartmentalised, so as to avoid the shutting off of the whole supply during cleaning (inconveniencing building users).; For the purpose of safety and security, provide a lock to water tank, so that only authorised personnel can access it. Ensure that the access is easy and safe, and for authorised persons only.; Comply with all security measures in accordance with SS 636 or equivalent.	Carry out general housekeeping within and around the tank room to remove any obstructions to maintenance access. Perform monthly cleaning of wash-out pipes to ensure proper flushing out of the water.; Remove sand and dirt deposits in cisterns and tanks. Remove rust stains and repaint affected parts as recommended. Prevent dirt, dust, insects, birds, etc. from entering the tank.; Carry out thorough cleaning and disinfection of tank interiors semi-annually.
Leakage from water tank; Corrosion of bolts and subsequent leaking; Of GRP tank	Ensure the proper design detailing of pipe penetrations at the tank to avoid leakage.; Avoid cracks in concrete tanks; ensure water-tightness, through proper structural design.; Specify appropriate water stops and sealants where pipes penetrate the structure.; Maintain a minimum air gap above maximum water level in accordance with SS 245, BS EN 13121-3 or equivalent.	Construct the tank body in accordance with specifications (additive, coating, and lining), and render as a monolithic and watertight container. Maintain the exact size and positions of installed devices in accordance with SS 245, BS EN 13121-3 or equivalent.; Commission tank by testing for water-tightness; check for any leakage, seepage, and water loss. Ensure that all components are functioning well.	Inspect drainage lines and basin.; Carry out routine checks for rusting of metal tanks and apply anti-corrosive paint/coatings where necessary.; Perform routine checks on float valve and liquid level indicator for damages to avoid potential overflow.
Corroded water tank body; Corroded tank body	The body of the water tank should be made of watertight and corrosion-resistant material, such as reinforced or pre-stressed concrete, steel, and glass fibre reinforced plastics in accordance with SS 245, BS EN 13121-3 or equivalent.	Structure of water tank should be constructed with adequate strength and be free from any deformation. Refer to BS EN 10088-2 for standards for a Stainless-Steel Sectional Water Storage Tank (Minimum Grade 316).	Ensure that the parts (e.g., pipes/strainer) and fittings (e.g. ball float, valves) are corrosion-resistant and can be replaced over time.; Perform timely re-application of coatings to avoid peeling and delamination of coat
Corroded and damaged water tank; Corroded water tank	Surface treatments, waterproof coating, or lining coating should be specified to resist water seepage and weathering.; Ensure that such finishes do not affect the stored water’s quality of hygiene in accordance with BS 8558, SS 636 or equivalent.	The water storage tank’s installation should be certified by a professional engineer to ensure that it is structurally sound with regard to hydrostatic pressures, deflection and leakage. Use disinfectant to clean water tanks in accordance with BS EN 805 or equivalent. Once disinfectant has been sprayed on inner surfaces and pipes for the designated period, it should be thoroughly cleaned/removed.	(for steel tanks), and water seepage (for concrete tanks).; Use disinfectant to clean water tanks in accordance with BS EN 805 or equivalent. Once disinfectant has been sprayed on inner surfaces and pipes for the designated period, it should be thoroughly cleaned/removed.
Overflow of water; Overflow of water as seen from underneath a tank	Decision on the size(s) of the tanks should be made based on water demand, supply, probability of pump failure, time needed for repairs, ratio of peak hours to average flow rate, provision of alternative supply or storage, etc. in accordance with BS 8558, SS 636 or equivalent.	Ensure that the tank is capable of handling various loads (as applicable) without showing cracks, stress or deformation in accordance with SS 245, BS EN 13121-3 or equivalent.	Carry out monthly inspections to check the operation of float valve or any other effective device for controlling the inflow of water. All valves should be periodically operated to ensure that the working parts are moving freely in accordance with BS 8558, SS 636 or equivalent.; Inspect condition of overflow warning alarm for the water tank. Inspect the condition of warning alarm which indicates when water levels fall below 50 mm from the invert level of the pipes.
Potable water tanks			Cleaning and disinfection of potable water tanks should be adopted in accordance with SS 636 or equivalent.