Health and Safety Briefing

Transcription

1 May 2013 Health and Safety Briefing SHEQ Notice No. 255 Read in conjunction with NR Safety Bulletin NRS 278 and Letter of Instruction This SSL SHEQ Notice applies to all staff, contractors, agency staff and visitors working on behalf of SSL on Network Rail Managed Infrastructure. Background The Office of Rail Regulation have issued Network Rail with two Improvement Notices with regards to their infrastructure Signalling Power Supply distribution Networks (650V, 400V, 230V). This includes location cabinets, power pillars or other known metallic cased trackside equipment (for simplicity to be referred to as a LOC). This also includes metal platforms on which they are mounted. It has been established that some of this equipment is deteriorating and there may be a risk of an electrical shock when touched either internally or externally. As a consequence of this, Network Rail have issued Safety Bulletin(s) NRS 278, NRS 278 (WSK) and a Letter of Instruction mandating revised arrangements for working with or testing Location Cases, Supply Terminal Pillars and Functional Supply Points. SSL recognise that their work involves working with or testing these LOC s, so until further notice all staff should avoid contact with this equipment until advised by a competent person that it is safe to do so. People who will be deemed to be competent are those SSL staff / sub contractors who have received and understood a briefing for NRS 278, the Letter of Instruction and SSL WIN/POW/003 NRS278 Compliance Testing at Metallic Case Trackside Equipment Housing. The competence shall also include one or more of the following:- A current Safety Procedures for Working on Electrical Equipment Certificate (SPWEE) LV Distribution systems competency C&G2391 Inspection, Testing & Certification of Electrical Installation (or equivalent) NICEIC Qualified Supervisor for SSL or SSL POW TiC Otherwise deemed competent by SSL SSL will issue competent staff / contractors with a supplementary Authority to Work (ATW) to cover this new requirement. This new competence and the briefings shall be recorded and retained on individuals files. SSL competent staff / contractors working with or testing the above described equipment shall always be accompanied by one or more persons. Working alone is not permitted. Before SSL competent staff / contractors carries out any work on these LOC s they shall be tested and inspected by a competent person in accordance with SSL WIN/POW/003 NRS278 Compliance Testing at Metallic Case Trackside Equipment Housing. This SSL Work Instruction Notice sets a safe condition of touching potentials below 60 volts. If the measured touch voltage is found to be above 60V then a first fault is present and the equipment surfaces are deemed to be LIVE and UNSAFE. It shall be reported to route fault control NDS24-7. No further work may take place on that equipment until advised that remedial action has been carried out by others and the equipment is now SAFE. Until then arrangements shall be made with NDS24-7 or other agreed Network Rail representative to protect others from incurring the risk of touching the equipment. NDS 24-7 telephone number is IF IN DOUBT ASK EVERY TIME.

2 Network Rail Safety Bulletin (WSK) (Wessex, Sussex and Kent only) I nspection and Work with signalling power supply systems containing equipment above nominal system voltage of 175 Volts For the attention of all staff and contractors working with signalling power supply systems This Safety Bulletin has been issued in Wessex, Sussex and Kent Routes only, to supersede Safety Bulletin NRSB No. 278, Inspection and work with signalling power supply systems containing equipment above 175 volts, and applies to all Staff and Contractors working on the Wessex, Sussex or Kent Routes who are required to work within any signalling equipment cases. Scope Until further notice, this bulletin applies when working on signalling or signalling power equipment within location cabinets, power pillars or other known metallic cased signalling equipment. For the purpose of this bulletin these are called equipment cases. It does not cover carrying out fault finding on signalling power equipment >175v where the requirements of NR/SMS/EL00 apply. General 1. When carrying out the electrical tests described in this bulletin, it is not necessary to scratch or scrape away any protective finish over the metal; the test probes may be placed onto the surface only. 2. In this bulletin standard gloves are defined as any gloves that do not contain neoprene or other conductive material. 3. When carrying out voltage testing the 60v limit applies whether using a multi-meter directly or when using a 150k Ohm shunt. Action Testing the equipment case Before touching the equipment case, staff will test the voltage between the equipment case and any exposed metal within 2 metres or the maximum reach using available test leads (E.g. guard rails, palisade fencing and other equipment cases but not running rails) using a standard issue multimeter. 1. If the result exceeds 60 volts ac then; a. Report as a fault for the appropriate warning sign to be put on the case or warning tape to be wound around the equipment case. b. Any work inside the case to be conducted in accordance with the procedures for live working detailed in NR/SMS/EL00; i.e. use of insulated tools, insulated gauntlets or insulated matting as appropriate. Continued on page 3

3 2. If the result of the test is less than 60 volts ac, you can open the equipment case wearing any standard gloves then; a. Test the voltage between any metallic housing within the equipment case containing equipment operating at 175V and the equipment case itself. b. If the result of this test exceeds 60 volts ac then; i. Report as a fault for the appropriate warning sign to be put on the case, or warning tape to be wound around the equipment case ii. Carry out any work inside the case in accordance with procedures for live working detailed in NR/ SMS/EL00: i.e. use of insulated tools, insulated gauntlets, insulated matting as appropriate. c. If the result of the test is less than 60 volts ac you can work using normal practice. Where you are unable to carry out the initial equipment case test. 3. If you cannot carry out the test on the outside of the equipment case, for example where there is no adjacent metalwork or other equipment cases, you should wear any standard gloves to enter the equipment case and then; a. Test the voltage between any metallic housing within the equipment case containing equipment operating at >175V and the equipment case itself. b. If the result of this additional test exceeds 60 volts ac then; i. Report as a fault to fault control for the appropriate warning sign to be put on the case or warning tape to be wound around the equipment case. ii. Carry out any work inside the case in accordance with procedures for live working detailed in NR/SMS/ EL00: i.e. use of insulated tools, insulated gauntlets, insulated matting as appropriate. c. If the result of the test is less than 60 volts you can work using normal practice. Additional If when you open up the equipment case and you see a live exposed busbar or connections where the voltage is greater than 175V; you must report a fault for protective covers to be applied or appropriate signs to be attached. Until protection is applied any work within the equipment case must be undertaken in accordance with the instructions for live working detailed in NR/SMS/EL00. An example of this is shown below; Fig- ure 1: Figure 1: Live exposed busbar and connections. For further advice, contact your respective Route Signalling or Electrification RAM.

4 Network Rail Safety Bulletin Inspection and Work with signalling power supply systems containing equipment above nominal system voltage of 175 Volts For the attention of all staff and contractors working with signalling power supply systems This safety bulletin reminds staff how to identify and control the electrical safety risk on signalling power supply systems operating at or above nominal voltage of 175 V This includes Location Cases, Supply Terminal Pillars and Functional Supply Points (FSP), herein all referred to as FSPs. The relevant electrical safety and lifesaving rules are:- Work should be carried out with the supply dead, unless it is unreasonable to work dead, and it is reasonable to work live. Never assume the equipment is safe, always test before touch Never undertake an activity unless you have been trained, assessed as competent and have the right equipment Working on live equipment is only permitted if It is considered that work with the system remaining live is reasonable, appropriate protective methods (which may include the use of insulated tools, insulated gloves with gauntlets or insulating mats) must be used in accordance with your training. During any work with live equipment, the risk of electrical injury must be continuously considered. If that risk can not be addressed, work must cease, and you must inform your supervisor. To work on live equipment, staff shall be deemed, by their employer, as being competent to carry out live working and have the necessary experience. Staff shall also be accompanied by one or more person. Any work in a FSP case shall be considered as working live if: The signalling power system has a first earth fault present. (ie Insulation resistance (IR) is below 20 kù or unknown) or There are exposed 650 V conductors or The case / metal parts have not been tested as below 60 V or The work involves accessing the 650 V equipment

5 Network Rail Safety Bulletin continued Action required by all persons wishing to access a Functional Supply Point: All staff should avoid making contact with equipment housings that could contain equipment operating at a voltage greater than 175 V. 1. Before opening the FSP, test before touch for any voltage between the case and any nearby metalwork, for example hand rail, barrier, OLE support or similar, within the touching distance of 2 metres1 from the case. If a voltage of 60 V or greater is measured, it should be considered to have a first earth fault, and hence the equipment shall be assumed live. 2. Open the case and check for any exposed live conductors within it, and avoid contact with any found. If any terminals greater than 175 V are exposed or inadequately shrouded, then the equipment should be assumed live. 3. Repeat test before touch for any voltage between all metal covers within the case, the FSP case and any nearby metalwork within the touching distance of 2 metres1 from the case. If a voltage of 60V or greater is measured, it should be considered to have a first earth fault and hence the equipment shall be assumed live. 4. When steps 1, 2 and 3 have been completed then visual inspection work or work on the signalling equipment can continue in accordance with existing controls. 5. On the completion of work repeat step 3 before securing the case. 6. If any touch voltage exceeds 60 V, securely affix a yellow and black warning tape around the FSP case several times and warning sign (yellow triangle as per first page of this Safety Bulletin), and report a first earth fault at the FSP to Route Fault Control. General Points A voltmeter with fully insulated leads in according to HSE Guidance Note GS38 Electrical Test Equipment for use by Electricians should be used to measure touch voltages. Insulated equipment must be in accordance with BS EN for insulated tools BS EN for insulated gloves with gauntlets, which must be Class 0 (Network Rail part number FBC90VSE) BS for insulated matting which must be Class 0 Equipment inside a FSP should be protected from rain when the doors are opened. You must never leave a FSP with the doors open and unattended. At the end of the work you must check that the electrical equipment is protected from the environment, for example by closing and securing the doors. Further guidance can be found in Network Rail Technical Instruction TI /400 V IT Signalling Power Supplies NR/L2/ General Instructions to Staff Working on S&T Equipment, Modules E022 and X002. NR/GN/ELP/ Insulation Monitoring of 650 V Earth - Free (IT System) Power Cables NR/L2/ELP/ Maintenance specification for fixed plant equipment NR/L3/RCS0216/DP10 Working on low voltage equipment NR/L3/ELP/27241 Fixed Plant Work instructions TNC8785 and Management plan Route based TNCs Example of inadequate shrouding of live conductors. Footnote1 If two times one meter test leads are not available, then these should be ordered as soon as possible. In the meantime, existing test leads should be used and surfaces outside the reach of existing test leads should not be touched.

6 Near Miss Clarborough Junction Alleged Near Miss Event: At on 16/04/13, the driver of 2R15 approaching Clarborough Junction, a converging junction in a strongly curved cutting, observed 3 trackworkers ahead who he believed were not clear of the line. The driver sounded his horn and carried out an emergency brake application. He reported the incident as a Near Miss and was shaken by the event and later needed to be relieved of duty. (Fig 1 indicates approx. driver s view of trackworkers) (NB: Photos taken post incident to replicate track side conditions) The trackworkers were walking in a position of safety which was less than 2m from the running line with their backs to traffic. Sidewalls of the bank, retaining walls and pinch points prevented the workers from being able to keep further than 2m away from the line. The safe system planned for access / egress was with a lookout, but because the COSS believed the group could remain at the minimum safe distance from the line, no lookout warning was employed. Local conditions meant that the approaching train had minimal sighting time of the group and without lookout warning and windy conditions affecting the audibility of the train horn, the group did not acknowledge the train until it was close. The trackworkers were unaware that the driver believed a near miss had occurred and were unharmed and unshaken by the event. Learning Points: COSS and Planners must remember that the SSOW planned and implemented for access and egress to and from the site of work is just as important as the SSOW implemented at the work location. COSS s must remember that if their workgroup is walking in a position of safety that is less than 2m from the running line, and the safe system planned is by lookout warning, it is imperative that lookout warning is still given when a trainapproaches and the group stay in a position of safety and acknowledge the approaching train in good time. Consider the effect on train drivers who may have limited sighting time of the group e.g. on a bend in a cutting. A driver may be shocked to see a group walking with their backs to traffic who appear to be close to the line and have not acknowledged the train. When works are planned or COSS s are implementing a SSOW for access / egress along the line, remember that a troughing route is not a safe cess walkway unless specifically notified that the troughing is a compliant walkway e.g. TroTred. If it is not possible to stand in the cess on the far side of a troughing route and there is no position of safety between the running rail and the troughing then this area must be treated as Limited Clearance. This may occur where a troughing route is less than 2m from the running line and obstructions such as retaining wall and the sidewalls of a cuttings or structures are present (fig.2) If the above situation of Limited clearance persists for greater than 50m and there is no compliant Position of Safety capable of accommodating 2 persons, to enable those persons to walk no more than 25m, this area shall be treated at Red Zone Prohibited. (Network Rail standard NR/L2/OHS/019 Safety of Persons Working on or near the line) Note: aathough the term Red Zone & Green Zone no longer exists in the Rule Book, the term is still applicable and used in Network Rail Standards i.e. NR/L2/OHS/019) COSS s must verify their SSOW pack at least one shift in advance or seek authorisation from the Responsible Manager. Planners should avoid, where possible, creating more than one SSOW pack for a COSS to undertake a job at one location. i.e. 2 SSOW packs catered for access/ egress to the location of work where the incident occurred. Responsible Managers are reminded to consider their role in the acceptance of the suitability of SSWOP produced by the planner and consider whether Line Blockages have been fully considered

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