Construction Water Safety Plan

Transcription

1 Construction Water Safety Plan

2 Date Reason for update Date Approved Issued Construction WSP is a June 2013 further requirement the management of water systems TBC Update as a result of Dec2013 feedback by regional group Feb 14 Updated due to Jun2014 implementation of HTM addendum pseudomonas July 13 Updated in relation to HSE July L8 part 2 HSG274 July 15 Update for flexible hoses dead legs and filling of system with water form a chlorine dioxide /Ag Cu plant July P a g e

3 INDEX Construction Water Safety Plan 1.0 Purpose 2.0 The Construction Water Safety Plan Logbook (CWSP logbook) 3.0 Design Stage 4.0 Initial and progress site meeting 5.0 Delivery and Storage of Material for the Water System 6.0 Inspection of Joints 7.0 Filling the System 8.0 Pressure Testing 9.0 Pre Flushing 10.0 Disinfection and Sampling 11.0 Commissioning 12.0 Pre-Handover 13.0 Flushing Record 14.0 Documentation for the CWSP Logbook at handover 15.0 Minor Modification and / or alteration 16.0 Risk Assessment APPENDIX- A Flushing Record Sheet REFERENCE DOCUMENTS 2 P a g e

4 Construction Water Safety Plan 1.0 Purpose This construction water safety plan (CWSP) is a guide to the management of water systems during construction works for new builds, major and minor works. This guide is not definitive, as the CWSP will change due to the complexity and size of each project. The following are the stages, in relation to water management, required to bring a project from conception to hand over. The water safety plan contains the general requirement /guidance to ensure that Trust water systems are managed during any construction works. 2.0 The Construction Water Safety Plan Logbook (CWSP logbook) The logbook is key to the management of the water systems and contains site information, process information, commissioning data and drawings relating to the project etc. a more comprehensive list is given in section 14 below. The logbook must be managed in an electronic format and accessible by the Design Team, Contractor and the Trust throughout the contract. The logbook must be established at design stage by the design team and shall be made available to the contractor at the commencement of the contract. The design team will be ultimately responsible for the management of the log book and shall ensure all required information is updated and provided and the log book is fully complete at point of handover of the building. Both a paper copy and an electronic copy must be available at handover of the project to the Trust. The log book should be reviewed at each progress meeting and were a shared portal is not available it shall be managed by the Design Team and downloaded by the Trust upon request. 3.0 Design Stage The Design Team in consultation with the Trust s nominated Water Safety Manager (WSM) and Infection Prevention and Control Team (IPCT) will review the initial design and drawings for the water system and agree the following: i. Number and location of all water outlet points. ii. Type of clinical wash hand basins (WHB) iii. Type of clinical WHB taps iv. Type of taps for all other outlets v. Clinical WHB station layout vi. Type and use of thermostatic mixing valve (TMV) (integral or remote from tap) vii. Type of non-return valve (NRV) to be used in the installation viii. Identify the WHB, sinks, shower, baths etc in the contractors work area that will be affected by the works 3 P a g e

5 ix. Identify all WHB, sinks, shower, baths etc in the contractors work area that will not be affected by the works, and determine how these outlets and the water supply will be managed during the works e.g. are the outlets to be isolated and drained or will a flushing regime be put in place. x. If a water supply for the contractor is to be provided in the work area, determine any precautions required to avoid contamination of the trust water supply from this source. xi. The return water system has been designed for a min. return temperature of 55 O C at the calorifier/plate Heat exchanger (PHE). xii. Location of all drainage points for the installation. xiii. Location of all sampling points and chemical purge point for initial disinfection and ongoing disinfection of the system. For works programmes over 30 days, consideration may be given to completely draining the entire system in the contractors work area. The agreed method to manage these outlets and the system must be recorded in the CWSP logbook. Following the above discussions the Design Team will produce an initial water safety plan drawing showing: (i) (ii) (iii) (iv) (v) Existing water services layout drawing showing all water services and water outlets and their associated isolation points serving the contractors work area. Where no accurate drawings exist then a full set of existing drawing shall be provide by the Design Team If a set of as fitted drawing are produced by the Trust then the Design Team shall verify the accuracy of the drawing against what is installed. Any new water services isolation points. If the existing isolation points are configured so that when isolated a dead leg upstream of the isolation point is created, then a new set of isolation valves must be installed at the tee off point on the distribution main. These new valves must be identified on the above drawing. If the contractor requires a water supply for the construction works then these points must be indicated on the above drawing. These water outlets must have a unique number attached to them so as to identify each point for the purpose of flushing. These unique numbers shall also be noted on the drawing. If a double check valve is required this must also be shown on the drawing. Highlight all WHBs, sinks, baths, showers or other water outlets in the work area which will remain unaffected by the works. Each outlet to be uniquely numbered both at the outlet and on the drawing for the purpose of flushing. The above drawing shall be held in the CWSP Logbook. 4 P a g e

6 4.0 Initial and progress site meeting Poor water management during a construction contract can have a major impact on patient safety and therefore it is a requirement that water management is an agenda item at all meeting. At the initial site meeting the following must be provided and inserted into the CWSP log book:- Contractor Contractor nominated person(s) responsible for water safety and management of the water system together with their contact details. Copy of the nominated person s training certificate on water safety (including Legionella and pseudomonas). If this is not available, then a date must be entered into the log as to when this will be completed and the date the training certificate will be available. Design team Trust Details of the project and the impact on the site water services, in and adjacent to, the Contractor Site Initial water safety plan drawing Trust nominated water safety manager for the project together with contact details At all progress site meeting any issue relating to water management must be recorded on the minutes of each meeting. 5.0 Delivery and Storage of Material for the Water System Care should be taken to prevent the entry of foreign material, which may enter the system during installation. The usual sources of foreign material are: (a) (b) (c) Attached to internal surfaces of pipe-work, fittings, valves etc, when delivered. Introduced to internal surfaces of pipe-work, fittings, valves etc, whilst stored. Introduced during construction. 5 P a g e

7 (i) Delivery and Storage The following are examples of care requirements: (a) All pipework should be inspected on delivery to ascertain cleanliness and be stored in a clean dry environment, with ends covered. (b) All pipework components should be delivered in suitable protective packaging and stored in clean covered bins, or bags, prior to use. (c) Particular care should be taken, when materials are delivered to the work place to avoid accidental ingress of material prior to construction. The above should be reinforced at each progress meeting and it would be expected that the design team would do spot checks while on site. (ii) During Installation The following are examples of care requirements: (a) All pipework and components should be inspected immediately prior to incorporation into the works and cleaned where necessary. (b) Open ends should be temporarily capped as the work proceeds, open ends should always be inspected prior to continuation. (c) Good practice should be adopted to limit the amount of excess material introduced by jointing methods employed. (d) The system shall be regularly checked during installation to ensure that open pipes, valve ends, cylinder connection etc. are sealed to prevent the ingress of dust/debris that could cause problems during commissioning and subsequent operation. (e) Checks shall also be made to ensure that fittings and materials comply with the UK plumbing Regulations, are Water Regulations Advisory Scheme (WRAS) approved and are those listed in the Water Fittings and Materials Directory. (f) The contractor MUST implement a Clean and Dirty Work protocol for all works in augmented care areas refer to the trusts water safety plan for an example of such a procedure 6 P a g e

8 (g) Flexible connection are not permitted on any sanitary ware (h) Redundant pipe work shall be completely removed including the tee and a straight length of pipe shall be fitted. The capping of blind ends is not permitted 6.0 Inspection of Joints Before pressure testing the Water manager shall identify a number of fittings to be cut out for examination to establish whether the quality of the finished joint meets the specification. The exact number to be cut out will vary according to the size of the installation, but as a guide, a ratio of one fitting per 400 installed shall be cut out. In any event, a minimum of two, and not normally more than five, fittings shall be cut out for examination. The fittings cut out shall be cut open (quartered longitudinally) and examined. The Design team will arrange for these fittings to be cut out for inspection under the contract. If unacceptable joints are found, adjacent fittings shall be cut out until the extent of any faulty workmanship has been established. The pipeline shall be made good and the tube and fitting shall be internally clean and free from particulate matter and some oxidation will be evident when hot joints are made. When copper pipe and capillary fittings are used, because of the viscosity of the brazing filler, full penetration may not be achieved. The minimum penetration at any point must be three times the wall thickness of the tube or 3mm, whichever is the greater. 7.0 Filling the System (i) Checks before Filling The installer s final inspection should aim to ensure that the system is complete, correctly installed and ready for the commencement of commissioning. This will avoid abortive time on behalf of the commissioning specialist. The system shall be filled only with potable water without particles 150 µm and this can be achieved using mechanical filters. If a disinfection system is being installed e.g. chlorine Dioxide or a copper /Silver ionisation then the system shall be filled with via these systems. Filling shall also comply with the requirements of the Water Supply (Water Fittings) Regulations for the prevention of backflow. This usually requires a break tank with a suitable air gap for indirect filling or a double check valve for direct filling. To ensure effective venting, fill slowly from the bottom upward thus forcing the air to high points for venting to atmosphere. Careful 7 P a g e

9 consideration should be given to the setting of valves and air vents before and during filling to avoid airlocks and excessive spillage, particularly where the fill water is treated. Care should be taken not to exceed the working pressure of the system when filling from a high pressure source. When the whole system is filled, disconnect the filling source, open the permanent supply connections and adjust the feed tank water levels. Safety warning: do not attempt to fill the system via a pressurisation set. A pressurisation set should only be used for final system top-up and pressurisation. A quick-fill bypass should be provided where appropriate to fill the system. 8.0 Pressure Testing The contractor to provide a method statement and risk assessment for all pressure tests carried out. These together with the test results shall be logged in the CWSP logbook. The installation inside buildings shall be pressure tested. This can be done either with chlorinated water or, where national regulations give permission, a low pressure oil free and clean air or inert gases may be used. Be aware of the possible danger from high gas or air pressure in the system. For hydrostatic pressure testing, pressure gauges and the recording apparatus shall have an accuracy of 0,02 MPa (0,2 bar) and shall be fitted at the lowest point in the system. The pressure gauge has a range of 0 MPa to 1,6 MPa (0 bar to 16 bar). Further information on pressure testing can be found in BS EN 806-4:2010(E) Specification for Installations inside Building Conveying Water for Human Consumption. 9.0 Pre Flushing Every new water service, cistern, distributing pipe, hot water cylinder or other appliance, and any extension or modification to such a service should be thoroughly flushed with potable water or chlorinated water before being put into service. The primary reason for this process is to remove any debris and organic matter, which encourages the growth of biofilms and subsequent deterioration of water quality. Additionally, the process removes any excess of flux, which can cause corrosion of copper pipes if left in place under conditions of low or no flow. All flushing must be recorded in the CWSP logbook. 8 P a g e

10 9.1 General Procedure The drinking water installation shall be flushed with potable water as soon as possible after installation and pressure testing and immediately before commissioning. Cold and hot water pipes shall be flushed separately. It shall be taken into account that particles in the water can damage the installation (corrosion). To prevent this, a mechanical filter in accordance with EN (no particles 150 µm) shall be used. Where a system is not brought into use within 7 days after flushing, disinfection and commissioning, it shall be flushed at regular intervals See section 12 below Pre- Handover. 9.2 Flushing with Water Precautions shall be taken to protect sensitive valves and equipment (eg WC flushing valves, thermostatic mixers, etc) against foreign particles arising from the installation of the system. Filters installed upstream of valves or installation, which cannot be replaced, shall be backwashed or renewed after flushing. Aerators, flow strainers, flow controllers, shower heads or hand showers, already installed with valves should be removed to increase flow. In case of concealed thermostatic valves and other sensitive valves, the manufacturer s instructions shall be followed. All servicing valves in the section to be flushed shall be fully opened. Depending on the size of the installation and on the layout of the pipework, the system may be flushed in sections. Flushing shall commence at the lowest storey of any building and proceed upward storey by storey. The minimum velocity for flushing the installation shall be at least 2 m/s. The water in the system shall be changed at least 20 times during flushing. At any particular floor level, the draw-off points shall be fully opened starting with the point most remote from the riser. After flushing the furthest, the draw-off points shall be closed, in order, commencing with the draw-off point at the upstream end of any circuit. 9 P a g e

11 A complete record of the flushing procedure shall be made and retained in the CWSP logbook. Note: it may be necessary to flush with warm water to adequately remove flux residues. 9.3 Flushing Procedure with Water/Air Mixture This is an alternative method of flushing and further guidance can be obtained in BS EN Section Disinfection and Sampling (i) Pre-disinfection Flushing At the time of construction and before the disinfection it may be necessary to leave the water in the system. Where this is the case, a regular regime of flushing should be undertaken at every outlet, HOT and COLD, twice weekly for three minutes. For augmented care areas Flushing must be carried out daily (7days per week). All flushing must be recorded in the CWSP log book. (See appendix A for a sample flushing sheet). This counteracts the effect of stagnation at exposed copper surfaces, which can lead to corrosion and the onset of blue water syndrome. This process is not a substitute for full system disinfection before occupancy. See section 12 below Pre-Handover If the system has been left flooded, then it shall be drained and flushed prior to disinfection. The water installations will be disinfected unless otherwise specified by the WSM or the IPCT (For small single dwellings, and minor extensions or alterations in any premises, all of which are low risk, disinfection may not be necessary, flushing may be sufficient sufficient). See section 15 below. (ii) Disinfection of the system Biocide / chloride solution injection points are to be provided at the point where the new pipework joins the existing system. These injection points take the form of valves, tees and a drain valve or physically removable section of pipe. This enables biocide /chloride solution to be injected into the new section of pipework and circulated or drawn through all new fittings. The removable section must be taken out or the drain valve locked open to prevent any possibility of biocide from contaminating the existing fresh water pipework during the disinfection process. 10 P a g e

12 Works should only be undertaken by properly trained, experienced and qualified operatives or contractors. Depending on the size of the installation, it may be necessary to divide the system into sections. During the whole disinfection procedure it must be ensured that there is no draw-off of any water. A sufficient alternative water supply shall be provided in buildings which are in use. Where any supply pipe within the installation is to be disinfected and there is a possibility that the disinfection substance can come into contact with the point of delivery, the water supplier shall be informed. Complete isolation from the incoming service pipe may be required. Where water that has been used to disinfect an installation is to be discharged into a drain or a sewer, the responsible authority shall be informed and their approval given before the discharge takes place. Where necessary, a neutralising agent may be required. The sequence of disinfection shall be: service pipes; supply pipes; cisterns; distributing pipes; as applicable. Further guidance on disinfection and sampling is detailed in HTM 04:01 Part A Section 17 and BS Section 5. Disinfection of the water services when the system is offline may be by: Thermal disinfection, The HWS temperature is raised to a level at which legionella will not survive, drawing it through to every outlet, and then flushing at a slow flow rate to maintain the high temperature for a suitable period (the contact time). This method is only applicable to HWS and is commonly used as a rapid response. It may be less effective than chemical disinfection and may not be practicable where the hot water supply is insufficient to maintain a high temperature throughout. Thermal disinfection of hot water services is carried out by raising the temperature of the whole contents of the calorifier and circulating water for at least an hour. Every hot water outlet throughout the system must then be flushed and, to be effective, the temperature at the calorifier should be maintained high enough to ensure that the temperature at the outlets does not fall below 60 C. Each tap and appliance should be run sequentially for at least five minutes at the full temperature (but not necessarily at full flow), and it should be measured and recorded. Thermal disinfection may prove to be ineffective where parts of the calorifier or water system fail to reach the required temperature for a long enough period. 11 P a g e

13 Chemical disinfection is a process of adding an effective agent such as chlorine or chlorine dioxide, drawing it through to every outlet, then closing the outlets and allowing it to remain in contact for a suitable period (known as the contact time). This method is commonly used when it is necessary to disinfect the cold water storage tanks and the whole system. The chemical disinfection of a water system is normally based on chlorine being dosed at 50 ppm for a minimum contact period of one hour, at the end of which the concentration should not be less than 30 ppm free residual chlorine. However, lower concentrations and longer contact times are considered acceptable, as set out in BS 8558:2011. (iii) Sampling Following disinfection the system shall be flushed and refilled and the following tests shall be carried out by a specialist contractor under the direction of the Design Team: Total viable counts (TVC) measured at 22 o C TVC measured at 37 o C Coliform bacteria E. Coli Pseudomonas aeruginosa Legionella (species); and Disinfection residuals (taken concurrently with the microbiological samples). Samples must be sent to an accredited lab for analysis. Sampling for legionella and pseudomonas should be carried out in accordance with BS 7592:2008 Sampling for Legionella organisms in water and related materials and the HTM addendum Pseudomonas aeruginosa advice for augmented care areas, respectively. Samples should be taken from separate hot and cold outlets rather than through mixer taps or outlets downstream of TMVs or showers. Samples should be clearly labelled with their source location and if collected pre- or post-flushing. The sampling points and the number of samples to be taken shall be agreed with the WSM and IPCT for the project. Sampling shall be carried out following disinfection (following the system being flushed and refilled.) Initially sampling for legionella bacteria and pseudomonas in the above areas will be carried out with all outlets being tested. A further set of samples shall be taken at all outlets in :- For LEGIONELLA --a further 5 days and 10 days For PSEUDOMONAS -- a further 3 days and 2 weeks and 4 weeks All results must be returned to the Trust for review by the WSM and the IPCT and all results must be recorded in the CWSP logbook. 12 P a g e

14 At the same time a water sample will be taken from the existing in service water main for the purpose of a results comparison. Where the TVC results indicate that the system has deteriorated with an increase in microbiological counts e.g. TVC results in excess of a 2 log difference above that found in incoming mains water, corrective action should be taken. All of the above tests must be clear of legionella and pseudomonas, E. Coli and Coliforms. Where pseudomonas aeruginosa, legionella, E Coli or coliform bacteria are present, the sampling point should be flushed and retested. If positive results persist, investigation into the cause should be carried out with a view to repeating the disinfection process. The required remedial works and further disinfection shall be agreed with the WSM or IPCT for the project. Further clear results at the above frequencies are required from the affected outlet before the system can be determined as satisfactory. Between each of the sampling periods a full flushing regime shall be carried out by the contractor (see section 12 below) Commissioning Correct commissioning is vitally important for the satisfactory operation of the hot and cold water systems. The designer shall prepare a commissioning brief for use by the contractor s commissioning engineer. This brief shall specify fully and clearly the extent of the commissioning and the objectives which must be achieved, and shall include:- Full design data on temperatures, water flow rates and pressures; Plant and equipment data; Commissioning procedures for thermostatic mixing valves in accordance with specification MES D08; Drawings and schematics; A list of test certificates to be provided. Water sampling of the existing and new installations The designer s attention is drawn to CIBSE Commissioning Code W: Water Distribution Systems 2010, which provides guidance on information that will be required by the commissioning engineers. In the preparation of commissioning instructions for domestic hot and cold water services, designers shall ensure that their work is in accordance with upto-date guidance from the Health Estates Investment Group (HEIG). The designer shall prepare for inclusion in the contract documents a list of tests and measurements that are to be taken by the contractor and 13 P a g e

15 recorded by him/her. These shall be witnessed by the project manager /WSM on his/her behalf and he/she, if approved, will circulate the results, in accordance with the client s instructions. All tests and measurement sheets and all results must be held in the CWSP logbook. A risk assessment should be performed before commissioning, to identify and take into account the potential for stagnation as this may lead to microbial growth where buildings are not to be fully occupied immediately or where systems are commissioned as occupation occurs, e.g. infrequently or intermittently used buildings. Ensure the incoming water supply tests are available as these shall be used as the reference tests against which the commissioning data shall be compared. The installation, on completion, shall be operated by the contractor as a whole, and subjected to functional or performance tests as specified by the design team. The commissioning manual shall be prepared by the contractor and submitted to the project manager for review by the WSM or IPCT before being issued in final form. Typical schedules of checks and performance tests shall be included in the commissioning manual together with record sheets. These shall be amended and supplemented as the designer considers necessary. Once the Trust s Project manager /Design team/ WSM is satisfied that the system meets the design intent, the final approved record sheets shall be completed and held in the CWSP logbook. The designer of the project shall witness the commissioning and testing of the entire installation and shall countersign any test/ record documents. The project manager/wsm shall countersign any relevant test record documents and shall have full access to witness the commissioning and testing of the installation as they determine appropriate. If performance is not acceptable, the matter shall be dealt with in accordance with the contract requirements. As installed record drawings, schematic diagrams, operating and maintenance instructions must be supplied at the time of handover. Certified records of pressure testing and disinfection shall also be made available. All flushing recorded shall be fully completed signed and be available. All documentation must be held in the CWSP logbook. The whole commissioning procedure shall be carried out under the guidance of the design team, although the involvement of specialists or manufacturers may be required for specific items of plant. Valid calibration certificates shall be submitted and checked for all measuring equipment to be used by the commissioning engineers prior to commencement of commissioning. All calibration certificates shall be made available and held in the CWSP logbook. The commissioning shall be carried out in a logical and methodical manner. All commissioning certificates shall be held on the CWSP logbook. 14 P a g e

16 (i) Commissioning and Testing Checklist The following is a summary of the key activities associated with the pre-commissioning and commissioning of hot and cold water storage and distribution systems. The list is not intended to be comprehensive (a) Cold Water Installations Pre-commissioning checks can be carried out on completion of the system installation, filling, pressure testing, disinfection, flushing and sampling. Pre-commissioning checks and tests to be applied are as follows. Check that: The systems have been provided and installed in accordance with specification and drawings, and that the systems are charged with water, vented and free from leaks; Water storage cisterns are free from distortion and leaks, are properly supported and secured, are provided with correctly fitting covers, and are in accordance with the Water Supply (Water Fittings) Regulations 1999; Distribution pipework is rigidly supported, insulated and incorporates adequate provisions for venting, draining, expansion, isolation and measurement of flow, temperature and pressure pipework systems have been pressure tested; pipework systems and storage cisterns have been flushed, disinfected, appropriate certification received, and that specified residual chlorine levels are attained; All sample results are available, signed off and satisfactory. Pipework systems and storage/break tanks are correctly identified and marked; Regulating valves and flow control devices operate freely; Water meter(s) is/are fitted correctly; Electrical isolation, cross-bonding and wiring of system components are installed in accordance with the current edition of BS 7671:2008. BMS monitoring points for tank cold water temperature, both at the inlet and the cold water storage temperature are correct and calibrated and a continuous log has been set up on the BMS system. A calibration certificate is available for the temperature probe Tanks have securely fitted lids C/W insect /vermin screens both on the overflow and vent Where multiple storage tanks are used the tanks are configured not to cause stagnation Tanks have a securely fitted access hatch. Cold water storage is 12 hours usage All insulation is fitted and pipework labelled and the pipework is segregated from hot services. 15 P a g e

17 Upon satisfactory completion of the pre-commissioning tests, the commissioning tests can commence. Commissioning checks and tests to be applied are as follows. Check that: Overflows run freely and discharged water does not cause flooding or damage, and that drain-down points flow when released and are free from leaks when shut; Float-operated valves function satisfactorily and are adjusted to give the correct water level; Control valves operate correctly and shut-off valves close tightly; All electrical circuits are tested and the pump motor direction of rotation is correct, and that electrical controls and alarms function correctly; Operation of any safety or anti-flood device is satisfactory; Circulating or lifting pumps are free from excessive noise, vibration and leaks, and there are no leaks at joints under maximum flow conditions; Remote control of pumps (if appropriate) are satisfactory; The installation is vented and regulated; The flow rate into, and out of, storage cisterns is recorded; All taps, mixers and outlets operate satisfactorily, and test and record mass flow from outlets in positions shown on contract drawings. (TMVs require hot and cold water for testing and commissioning. Type 3 TMVs are commissioned in accordance with MES DO8); Temperature of water in storage cisterns and at taps are appropriate; All branches and pipes to individual outlets can deliver cold water at a temperature close (min increase 2 O C) to the incoming mains supply within 2 minutes of running. Full load current of components does not exceed the recommended values; The running current of components does not exceed the recommended values; Pump thermal overload trips are set; System schematic is displayed in a frame in the relevant plantroom, complete with valve schedule. (b) Hot Water Installations Pre-commissioning checks can be carried out on completion of the system installation, filling, pressure testing, disinfection, flushing and sampling. Pre-commissioning checks and tests to be applied are as follows. Check that: 16 P a g e

18 All Pressure test certificates, flushing records, disinfection certificates and sample results are available, signed off and satisfactory. Systems have been provided and installed in accordance with the specification and drawings; The system is charged with water, vented and free from leaks; Hot water storage vessels are free from leaks and are properly supported and secures; Distribution pipework is rigidly supported, insulated, labelled and incorporates adequate provision for venting, drainage, expansion, isolation, and measurement of flow, temperature and pressure Pipework systems, storage cylinders etc have been pressure tested, flushed and disinfected, and appropriate certification has been received, and that specified residual chlorine levels are attained; Pipework systems, calorifiers and cisterns are correctly identified and marked; Regulating valves and flow control devices operate freely; All control and regulating valves are labelled or marked to correspond with reference numbers on contract drawings/ schematics; Electrical isolation, cross-bonding and wiring of system components is installed in accordance with the current edition of BS 7671:2008; Hot water calorifier is vented to an open tundish and not via the CWS tank and shall provide visible warning of a fault condition The drain on the calorifier located in an accessible point and as close as possible to the vessel so that accumulated matter can be safely drained. Pump thermal overload trips are set; system schematic is displayed in a frame in the relevant plant room, complete with valve schedule. Upon satisfactory completion of the pre-commissioning checks, the commissioning checks and tests can then be started. Commissioning checks and tests to be applied are as follows. Check that: Drain down points flow when released and are free from leaks when shut, and that air vents and release valves open correctly and are airtight when shut off; All temperature and other controls are adjusted and calibrated to agreed design limits of system performance e.g. 60 O C at calorifiers /PHE and a min. of 55 O C return at calorifier / plate heat exchanger 17 P a g e

19 All electrical circuits are tested and the pump motor director of rotation is correct, and that electrical controls and alarms function correctly; Control valves operate correctly and shut-off valves close tightly; Heat exchangers operate satisfactorily; Primary heating circuits are adjusted and regulated, and thermostatic settings are correct; and that bypass circuits and automatic control valves operate correctly; Circulating pumps are free from excessive noise, vibration and leaks; Remote and automatic control of pumps (if appropriate) is satisfactory, and there are no leaks at joints under maximum flow conditions; Secondary circuits are regulated and vented; Thermostatic mixing devices and regulating valves are adjusted and set to desired values (TMVs require hot and cold water for testing and commissioning, and shall be commissioned in accordance with MES D08); All taps, mixers and outlets are the correct type and operate satisfactorily; Water flow quantities at all plant items, regulating valves and flow-measuring valves are recorded; Mass flow from taps, mains and other outlets in positions shown on contract drawings are satisfactory; Pressure drop at heat exchangers at full design demand flow is tested and recorded; Hydraulic balancing of hot water secondary circulation system is carried out to ensure that minimum temperatures are achieved in all parts of the circuit; Full load current of components does not exceed the recommended values; The running current of components does not exceed the recommended values; Pump thermal overload trips are set. Temperature monitoring on Flow and return and base of all calorifiers/phe are in place, calibrated and a continuous log set up on the BMS system. Temperature of calorifier /PHE and at taps is appropriate; All branches and pipes to individual outlets can deliver hot water at a min. temperature of 55 O C at each outlet within 1 minutes of running. If two of more calorifiers/phe are in use, are they connected in parallel and able to provide hot water at 60 O C and the storage and daily expected draw off can still result in a 60 O C temp being maintained. Has the hot water return legs, Principle, subordinate and tertiary loops been balanced and the return temperature monitored and logged. Min temp 55 O C Have all point of use heaters been checked and set at 60 O C 18 P a g e

20 (c) Expansion vessels To minimise the risk of microbial growth, have the expansion vessels been installed: o In cool areas on cold flowing pipes; o Mounted as close to the incoming water supply as possible; o Mounted vertically on pipework to minimise any trapping of debris; o Has an isolation and drain valve been fitted to aid flushing and sampling; o Has they been designed /sized to minimise the volume retained within them; o Designed to stimulate flow within the vessel. (d) Temperature Testing These tests shall be performed prior to contractual handover and bringing the system into use. Separate calibrated thermostatic measuring and recording equipment shall be used, that is, independent of any building management system. It will be necessary to have systems fully operational and to simulate typical draw-off of water. Tests shall include: Measuring the incoming water temperature at the main water meter; Testing the inlet, outlet and surface water temperatures of cisterns and cold water feed/header tanks for the hot water calorifiers. The temperature shall not be greater than 2 o C above that measured at the incoming water temperature; Testing the flow and return temperatures at connections to calofifiers and water heaters. These shall not be less than 60 o C and 55 o C respectively; Testing the temperature in branches of hot water circulating systems installed in all departments to ensure that the system has been balanced, and that under no draw-off conditions 55 o C is achieved in the circulating system at outlets furthermost from the calorifier/heater; Testing sections of a non-recirculating hot water system at branches to ensure that the trace heating is effective and that under no-flow conditions 55 o C is achieved; Testing single hot water outlets and inlets to mixing valves to ensure that a minimum of 55 o C is achieved within 1 min; Testing single cold water outlets and inlets to mixing valves to ensure that temperature equilibrium below 20 o C is achieved within 2 min. Monitor the hot water return legs, Principle, subordinate and tertiary loops return temperature Min temp 55 O C 19 P a g e

21 Note 1 L8 permits a period of 1 minute to achieve and equilibrium temperature of 55 o C. A minimum of 55 o C may be required for the operation of suitable mixing devices required to provide safe hot water at the upper limit of the recommended range. Hot water at 55 o C is required in many cases for reasons of food hygiene or decontamination requirements, for example in kitchens and sluice rooms. In a properly balanced hot water circulating system, with the circulation taken close to the draw-off point, achieving temperature shall be virtually instantaneous. At a typical flow to a wash-hand basin of 4.5 L/m, 1 min to achieve temperature would indicate a 25 m dead-leg of 15mm pipe or that the system is out of balance. Note 2 L8 permits a period of 2 minutes to achieve an equilibrium temperature below 20 o C. Achieving this minimum requirement would be indicative of an exceptionally under-utilised water system in an unoccupied building. During commissioning, therefore, it is essential to encourage draw-off to simulate normal usage. At a typical flow to a wash-hand basin of 4.5 L/m, 2 min to achieve temperature would indicate a 50 m dead-leg of 15mm pipe or that stagnation is occurring. (e) Commissioning Information It is essential that a full report of all commissioning and testing activities is compiled and handed over to be incorporated within the operation and maintenance manuals and held on the CWSP logbook. These commissioning and testing records will be required so that subsequent maintenance and periodic checks can be made to ensure that the installation continues to operate as intended. Such information will include results of temperature checks on the cold water supply, hot water circulating systems and trace-heated hot water installations, and commissioning and in-service test data for type 3 TMVs. All flushing and disinfection records shall also be included. The information shall also include identification of, and test results for, sentinel taps. Where continuous water treatment is installed, the commissioning records shall include details of settings of the equipment, dosing rates and requirements for testing. 20 P a g e

22 Operation and maintenance manuals shall be in accordance with BSRIA s (1990) application Guide 1/87; Operation and Maintenance Manuals for Building Services Installations. In addition, operating and maintenance manuals shall be provided for all building services installation. These shall include all relevant sections as described in HTM Pre-Handover Following full commissioning of the system and prior to handover to the Trust, the contractor shall be responsible for maintaining the quality of the water system. The Design Team shall issue an as fitted drawing showing all WHBs, showers, baths and all other water outlets in the contracted work area. Each of these shall be physically labelled with a laser printer label using the Trust s unique whb/tap numbering system. The as fitted and schematic drawing shall also detail the unique number. A schedule shall be provided on the drawing to detail each outlet. The schedule shall have the following headings: Unique number provided by the Trust Room description- kitchen, shower room, single bed ward, etc. Outlet description whb, shower, bath, sink etc From the time the system is first filled with water the contractor will flush all outlets including WCs twice per week eg Monday and Thursday or Tuesday and Friday and this shall remain in place until the building is handed over to the Trust. For augmented care areas the flushing shall be carried out daily (7 days per week). All flushing must be recorded in the CWSP log book (a sample flushing sheet in given in appendix A). The protocol for flushing is as follows and shall be carried out at the frequency as detailed above: (i) Sequence for flushing hot and cold taps Cold Tap Open the cold tap slowly at first (with the minimum of spray) to avoid any splashing or over spray unto the surrounding surfaces. Once open continue to run for a period of three minutes. At the end of this time the tap can be turned off. Record on the flushing sheet. Hot Tap 21 P a g e

23 Open the hot tap slowly at first (with minimum of spray) to avoid any splashing or over spray unto the surrounding surfaces. Once open continue to run for a period of three minutes. At the end of this time the tap can be turned off. Record on the flushing sheet. For single lever taps the taps should be opened and flushed in both the cold position and hot position each for three minutes. Sequence for Flushing Showers Remove the shower head from the holder and allow the hose to hang down the wall, adjust the shower hose slide rail to avoid the shower head coming in to contact with the ground. (For fixed shower roses this will not be possible and a towel etc. may be used to defect the water while the shower value is turned on and off. The towel should not be allowed to touch the shower rose). Turn the shower control knob/lever to the full open position. Once open continue to run for a period of three minutes. At the end of this time the shower can be turned off and the shower head returned to the holder. Record on the flushing sheet WC Flushing Flush each toilet as per the frequency detailed above. Record on the flushing sheet. Note (i) - at the time of flushing the temperature of the water shall also be recorded on the flushing sheet Flushing Record The flushing record sheet as detailed in Appendix- A shall be used by the contractor. All flushing records shall be held on the CWSP logbook Documentation for the CWSP Logbook at handover (i) General It is essential that a full report of all commissioning and testing activities and all information requested in this guidance is incorporated within the CWSP logbook. As a minimum, for new installations or major refurbishment, the 22 P a g e

24 contract shall require the following documents and drawings to be supplied; Initial Water safety plan drawing Project description Nominated staff to manage waters system during the project The name of any water specialist company employed to carried specialist task on the water system during the contract Staff Training Records and Training Content. Details of how water outlet (live or dead) are being managed; Calibration certificates form all test and monitoring equipment. Full manufacturing details, including batch numbers of all pipes and fittings; Full records and certificates of pressure tests for all sections of pipework; Settings of all balancing valves, with readings of flow rates where applicable; Full details of each item of plant, including arrangement drawings and appropriate test certificates; Full details of water treatment parameters and operating modes and settings; Confirmation of disinfection procedures to EN 806, and results of post-disinfection microbiological analysis. Certification of Disinfection and that there is adequate residual disinfection available on completion of the cleaning process. Records of the free chlorine residuals achieved at the time of certification for the disinfection process; Full records confirming that all materials and fittings hold WRAS or equivalent accreditation; All method statements and risk assessments for all works, maintenance, testing, on the water systems during the project; Results of temperature checks on the cold water supply and hot water circulating systems at commissioning and pre handover; Commissioning test data for Type 3 TMVs; Identification of, and test results for, sentinel taps; Flushing logs Water temperature logs including details of all actions carried out as a result of any non-conformity; Copies of all operator/supervisor field notes and instructions for cleaning and disinfection; Copies of all field records of on-site tests; Copy of any sampling audits carried out together with notes of corrective action taken to mitigate any non-conformity; Copies of material safety sheets for the disinfectants uses; 23 P a g e

25 As-fitted drawings showing clearly the location of balancing valves, flows and settings, isolation valves, drain valves, all sanitary ware and including schedule and unique numbering scheme of water outlets, all principle loops, subordinate loops and tertiary loops all temp probe locations, strainers, filters or other components that are potentially relevant to the legionella and pseudomonas risk. Full details of maintenance requirements; Location of continuous water treatment installed, the commissioning records should include details of settings of the equipment, dosing rates and requirements for testing; Any Legionella Risk Assessment carried out; Any other relevant documentation which might provide assistance in the on-going management or assessment of water quality in the system The reviewed and updated/new schematic drawings for the area which may include the area of refurbishment or works being carried out. The new schematic drawing must update the Trusts master drawing and incorporate all of the works changes carried out. An individual/ separate drawing of the works/ refurbishment carried out will not be accepted as a substitute for the updating of the Trusts master drawing the schematic must show all of the works, including the plant rooms showing all valves and items of plant, services etc. Where this does not exist a new schematic drawing shall be provided. The schematic drawing The content and extent of which must be agreed with the water safety manager for the project (see below for information on schematic drawings); Schematic drawings: Existing schematic drawings are held in the Estates computer drawing database. Drawings/schematics will be produced on request. Water system schematics are produced for all hot and cold water systems, and shall include the location of all of point of use water heaters. The schematics show the storage systems in plant rooms and tank rooms as well as the full distribution systems. For each water system a schematic or drawing shall provide to show: Origin of water supply; General layout of the system All design temperatures settings ; All associated storage and header tanks; All standby equipment; Any parts of the system that may be out of use temporarily; Any problem areas such as dead legs; 24 P a g e

26 All purge, vent, disinfectant injection points and test points; Main isolation points. All system plant, e.g. water softeners, filters, strainers, pumps, non-return valves and all outlets, for example showers, wash hand basins etc.; All associated pipework and piping routes. All HWS principle loops All HWS subordinate loops All HWS tertiary loops All temperature probe points for manual testing or BMS probes All water outlet, uniquely numbered as per Trust s numbering system Drawings/schematic are to be held in the CWSP logbook. System schematics shall be displayed in a frame in the relevant plant room, complete with a valve schedule Minor Modification and / or alteration The following shall be read in conjunction with the above guidance. The extent of the necessary precautions, testing, etc. will depend on each individual project. However the final requirements will be determined by either the WSM or the IPCT and their decision will be final. It is the responsibility of the design team to determine the water safety requirements prior to design stage and to have these approved by the WSM /IPCT Minor Plumbing Alterations Where small alterations or maintenance tasks on water systems have been carried out, then re-commissioning may require no more than thorough flushing of the systems. This can be followed by sampling and analysis of the water if considered necessary by the WSM/IPCT, although this is not expected to be required after minor maintenance related works such as replacement of individual water fittings. This relaxation is only permissible where the extent of the work is small (fewer than 6 fittings and less than 5 metres of new pipe per service, as a guide) and all fittings and pipe used on the installation are new and EITHER taken from the manufacturer s sealed packing just before use, OR pre-chlorinated immediately before use. Pre-chlorination can be simply achieved by immersing and agitating the fittings for 5 minutes in a 1,000 ppm solution of sodium hypochlorite. The COSHH Regulations apply to the use of such solutions at work a risk assessment should be prepared and the appropriate physical precautions, including PPE must be taken. 25 P a g e