2001-0046253 I003 Lock Out - Tag Out - Try Out Field of application RWE Generation NL Valid until 20-11-2020 Document information Version Version date Authorisation V3.2 20-11-2017 Manager Health, Safety and Security - R. Kamst Changes compared with the previous version - V0.2 version adapted for the Eemshaven site during pilot SAP-WCM. - V1.0 comments on BEI incorporated, definitive version. - V2.0 definitive version I-003 GCN. - V3.0 I-003 adapted in accordance with P003 - V3.1 I-003 adjusted in connection with Sense & Simplicity - V3.2 Remarks from Organisation incorporated, including a number of LOTO locks. Purpose of instruction The purpose of the LOTOTO instructions is to prevent the possibility of safety isolated equipment from being started up unintentionally or of power/medium being released while works are being carried out. Related documents Document type Title Code Input Input Input Output Work Clearance Management (WCM) Management of electrical installations Work instructions on parting off Form for breaking open safety isolation P081 UPI-012 I003-001 Page 1 of 10
Introduction The so-called Lock out, Tag out and Try out principle which utilises unique locks and key safes or LOTO boxes is used to protect against reconnection and to indicate safety isolation activities. The issuing department is responsible for decommissioning and for carrying out the safety isolation of (parts of) an installation correctly. Operations will be carried out based on the safety isolation list, BEI, EVD and P&IDs. Safety-isolated parts of the installation will be provided with a unique lock and a safety isolation label. Correct safety isolation is demonstrated by means of the try-out principle. Order of preference for making safe 1. Disconnection: the installation of a physical means of separation in order to ensure that the components to be worked on are no longer connected to the parts of the installation which have not been safety isolated; 2. Blind flange/connecting flange: a blind flange is used to close off an open flange connection. A connecting flange is used to close off part of a pipe and is installed between two consecutive flanges, as close as possible to the work area. Blind and connecting flanges are to be certified for material class for the relevant system pressure; 3. Double block and bleed: the safety isolation of (parts of) an installation by closing 2 valves and demonstrably depressurising the pipe section in-between by means of an open drain; 4. Single safety isolation: making (parts of) an installation safe by closing a single valve and demonstrably depressurising the relevant pipe section after this valve by means of an open connection to the outside air and then keeping it depressurised. In this case, the works are regarded as a high-risk activity and a TRA will need to be set up. Securing and marking safety isolated parts of an installation Use of locks and LOTO box LOTO locks are used in order to ensure that (part of) an installation that has been made safe remains in the desired state. There are 3 types of lock: one from Operations and two from the E- Maintenance department, namely one for high-voltage components and one for low-voltage components. The lock from Operations is the first to be attached and the last to be removed. The keys to these locks are stored in the LOTO box, along with the safety isolation list, and then the holder of the work permit is given the key to the said LOTO box. Page 2 of 10
This gives the permit holder and the permit issuer the assurance that the state of the installation cannot change without them both being aware of it. Page 3 of 10
If the works are stopped, for a short or long period of time, a key will be kept by the holder as standard. In situations where the key to the LOTO box has to be returned to the issuer of the work permit, when that key is issued it will need to be demonstrated again that the installation or the part of the installation is still safely isolated. Attachment of safety isolation labels Any component that is set to a safe state so that work can be carried out is to be marked with a label which is to contain a unique code or the maintenance order number and the serial number of the safety isolation list. If a component is set to a safe state for a number of activities at the same time, one label and one lock are to be attached to that component for every maintenance order number. This will prevent a safe state from being terminated while (other) works are still in progress. If it is not practically possible to attach multiple locks, the option of nesting the LOTO boxes in question can also be chosen. Electrical safety isolation work Electrical safety isolation before carrying out mechanical work The process-related safety isolation of the electrical installation is to be carried out by the issuing department while observing UPI-012. Electrical safety isolation before carrying out electrical work If electrical safety isolation and/or separation has to be carried out, possibly by referring to a circuit diagram, or where it is necessary to remove fuses, to remove switching cabinets, to install earths or to detach cabling, then this is to be carried out in accordance with UPI-012 Page 4 of 10
Testing of LOTO safety isolations A check (Try Out) must always be carried out in order to make sure that all the safety isolation actions performed have been successful. This check will be carried out by the issuing department. If necessary, seek assistance from an expert. Establishing isolation In the case of work on electrical components, it must at least be proven that they have been made dead in accordance with UPI-012. Establishing lack of pressure After the safety isolation of process systems, a check is to be carried out in order to establish that there is no pressure. It must always be possible to prove that the lack of pressure has been established. Here, it is preferable for the pressure in a pipe/component to be confirmed by means of visual inspection. If it is not possible to depressurise a system before starting work or to establish that there is no pressure within it by means of visual inspection, then this must be specified on the work permit and discussed with the persons carrying out the work. The work permit will then be classified as high risk and a TRA will be set up. Medium-free All systems which are safety isolated before maintenance is carried out are to be supplied energyand medium-free. If it is not possible to supply a system energy- and medium-free, then this must be specified on the work permit and discussed with the persons carrying out the work. The work permit will then be classified as high risk and a TRA will be jointly set up. If it is necessary to carry out work on a system which has contained or does contain hazardous substances, then proof must be provided that all those substances have been removed. The check to be carried out before work can start on chemical systems will consist of taking samples of the latest flushing medium or arranging for this to be done. Page 5 of 10
Terminology & abbreviations Abbreviation/term End consumer Safety isolation label (Tag) Meaning Last component in an electrical chain, e.g. an electric motor. Label that is attached to a component in order to indicate that the state of that component must not be changed. The safety isolation sticker that will be printed from SAP is to be attached to the label. Label with (WCM) sticker Locks and chains Parts of the installation can be locked using locks, in conjunction with chains or specially designed steel wires, or other suitable attributes. Sealing tape If it is not possible to attach a lock, you can also use special sealing tape. Just like the lock, this tape may only be attached and removed by persons who are authorised to do so. This method of locking must also be accompanied by the safety isolation label. If it is not possible at all to lock part of an installation in order to prevent it from being switched on, then measures for reducing or monitoring the risk must be detailed in a risk analysis (TRA). Page 6 of 10
LOTO box Safe that can only be opened using a number of safe keys. This safe is used to store the keys to the locks used to block installation components after safety isolation, along with the original safety isolation list/circuit diagram. The safe cannot be opened in order to take out the locking keys and the safety isolation list until all the relevant parties have returned their safe key. Circuit diagram Diagram showing all the circuits in the high and low voltage networks which produce a desired operating situation in respect of the electrical installation. See also instructions UPI-012 Locks Safety isolation list LOTOTO Unique padlocks which are attached to a component in order to prevent the state from being changed. The person carrying out the work is given a key to the LOTO box so that every person involved in carrying out the work has a personal means of blocking as it were. (see operation of key safe) The safety isolation list will indicate the state required for (a part of) an installation or component after safety isolation in order to enable work to be carried out safely on the system or component. Lock Out Tag Out Try Out: this is a safety procedure where machines and other power sources are switched off during inspection, maintenance and/or repairs. This procedure must ensure that personnel are protected against the hazards associated with machines which can be started up and other forms of (chemical) energy that can be released unexpectedly. Page 7 of 10
Methods for making safe and definitions Disconnection Blind flange/connecting flange Double block & bleed Single safety isolation Mechanical blocking The installation of a physical means of separation in order to ensure that the components to be worked on are no longer connected to the parts of the installation which have not been safety isolated A blind flange is used to close off an open flange. A connecting flange is used to close off a pipe and is installed between two consecutive flanges, as close as possible to the work area. Blind and connecting flanges are to be certified for pressure and material class. See also the work instructions on parting off using blind flanges, I003-001 The safety isolation of (parts of) an installation by closing two values (installed close together), depressurising the pipe section in-between by means of an open drain and then keeping it depressurised. After a blind/connecting flange, this method of safety isolation is the safest. Making (parts of) an installation safe by closing a single valve and depressurising the relevant pipe section after this valve by means of an open connection to the outside air and then keeping it depressurised. The process-based blocking of (part of) an installation in order to prevent the uncontrolled leakage of a medium (liquid, gas or solid). Mechanical blocking of (parts of) a hydraulically/ pneumatically controlled installation. Preventing components from starting up unintentionally (driven by the relevant medium) If the closing off/disconnection of the control medium is unsuccessful, it will have to be blocked mechanically so that this (or these parts of the) installation cannot start up. This also applies to components that could start up again unintentionally after the removal of drive systems. The strength of the mechanical safety device is to be tested beforehand. Page 8 of 10
Sewer plugs/pipe balloons Sewer plugs (balloons) can be used to safely isolate (parts of) an installation for which double sealing off is required. The Sewer Plug will then usually be fitted next to an existing shut-off valve. This method is used by means of collaboration with the maintenance department or a specialist company. Electrical safety isolation to enable electrical work to be carried out Electrical safety isolation to enable mechanical work to be carried out The safety isolation and possibly earthing of electrical equipment in accordance with UPI 012 so that it is, and remains, disconnected from the power supply and dead. The safety isolation and blocking of switches in order to prevent the drive motor or equipment from being switched on. Safety isolation is achieved by interrupting the main circuit. Safety isolation is achieved by interrupting the main circuit. Standardisation Cancellation of the measures taken during safety isolation following the completion of works Page 9 of 10
Standardisation After the works on the (parts of the) installation have been completed and the work permit and the key have been returned by the Holder, the issuing department will remove all labels and locks based on the safety isolation list and P&IDs. The order to make the (parts of the) installation ready for operation again can then be given. After the standardisation of the safety isolation, the safety isolation list along with the work permit will be kept by the permit issuer for a minimum of 3 months (possibly in digital format). Cancelling of LOTO under special circumstances This cutting procedure is only applied in exceptional circumstances and will need to be authorised by the site manager or his deputy. All the relevant parties are to be notified beforehand that this procedure is going to be applied. If it turns out that the key to a lock/key safe cannot be found, the following method is to be followed in order to remove the lock or break open the key safe. 1. Identify the safe key (lock number) in question and the person to whom it was given. 2. All the relevant parties will be notified that this procedure is going to be followed. 3. Complete the breaking open safety isolation form. 4. Always get the Team Leader Operations and in the case of electrical safety isolation the person responsible for installation too to sign for the breaking open of the lock or key safe in question within the framework of UPI-012. By making that decision, they also take over responsibility for the related works or part of the installation. 5. The site manager should also sign when a key safe or lock is broken open. 6. If the key in question belongs to a contractor, complete a Deviant Delivery Report (DDR). 7. Break open the lock or the key safe. 8. Discuss the cutting of the lock at the morning meeting. 9. The cutting form is to be archived by the Team Leader Operations. Page 10 of 10