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Permit to Work system

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This document outlines the critical components of a Permit to Work system, emphasizing its role in ensuring workplace safety during various types of operations. It delineates the responsibilities of the Issuing and Receiving authorities and describes specific permit types, such as Hot Work, Cold Work, and Vessel Entry Work, along with their validity periods and essential requirements for ensuring safety and risk management. Additionally, it addresses post-job requirements and safety protocols associated with working at height and confined spaces.

Industrial Management SAFETY Permit To Work System Engr. Muhammad Sajid Lecturer Department of Chemical Engineering, UOG Scope of The Session 1. 2. 3. 4. 5. 6. Permit to work system – General Requirement Isolation from hazardous materials Isolation from sources of energy Hot work Work at height/roofs Confined space entry  All PTW - Participants persons approved either to issue or accept permits to work should have received sufficient training and on job experience.  This session shall be validated and recorded by management.  This requirement also applies to contractors staff, if working independently. 1. Permit to work system – General Requirement Work Permit System Hazard Identification • Obvious Hazards • Potential Hazards Work Permit System Takes care of Hazards from : • • • • • • Electrical Source Instruments Interlocks Pressure Temperature Hazardous Materials Others Work Permit When Needed When agency doing the job does not have operating control of the Equipment. Types of Permits  Cold Work Permit  Hot Work Permit  Entry into confined spaces  Working on Height  Excavations/break-ins (walls/ceilings)  Electrical Isolation.  DCS Permit??? Basic Characteristics of Work Permit • • • • • • • • • • Clear and complete job description. Location of the work - Area The time span - date and time the permit comes into effect and the period of validity. All known hazards to be listed. List precautions to be taken to address these hazards. (Job Risk Assessment) Electrical, process and mechanical isolation One permit for one job for one equipment to be issued. Communicate/reference to all other permits / authorizations. Define PPEs Any other precaution. Cold & Hot Work Permits Vessel Entry & working at Height Work Permit Documentation  Display hard copy of the PTW at the work site for checking  Issuer to keep the upper copy  After the completion of the job,hard copy to be retained by the issuer& upper copy by the receiver for audit purposes. Work Permit Validity • Cold Work Permit:-8 Hrs(Extendable for 30 minutes by the going shift in charge only) • Hot Work Permit:-8Hrs(Extendable for 30 minutes by the going shift in charge only) • Vessel Entry Work Permit:-8 Hrs only, Not Extendable. • Excavation & Break-in:-8Hrs(Extendable for 30 minutes by the going shift in charge only) • Incase after the issuance of work permit job is not started within 2 hrs, issue the new work permit. • During emergency all work permits will be suspended. Work Permit Issuing Authority • Shift Engineer/Field Engineer/ Supervisor authorized by Unit Manager. Work Permit Receiving Authority Area Managers/ designated staff of the Engineering departments. Joint Visit ???? •A joint visit of the issuer and the acceptor to the site of the work is almost always essential to discuss the hazards associated with that job. •The signature of the issuer AND the acceptor should be recorded on the permit Remember The permit itself does not make the job safe! Issuing Authority Role of Issuing Authority • • • • • Evaluate and discuss with the Receiving authority the risks involved and precautions needed (Joint Visit) Joint visit is mandatory even for routine work permit jobs. Determine Impact on other activities on the plant. Ensure that work does not constitute an unauthorized Modification(if yes, then work after following Plant Modification & Control Procedure SP-8-00-048 & approval) Inform to all people before work start who might get affected due to job. Ensure that all pre-requirements of the job are fulfilled Continued… Role of Issuing Authority • • • • • • Ensure Process isolation Ensure that procedure is complete in its entirety. Enter the proper PPEs in work permit. Ensure Electrical isolation (Electrical isolation must be check physically by giving start signal) Ensure the job is proper hand over. Job status at the end of the job completion. • Ensure that job is done within the intent of the work permit. Visit Site frequently • Extend the permit time(30 minutes), if job not completed within the shift. The new shift will issue the new permit. Receiving Authority Role of Receiving Authority • • • • • • Together with issuer assess risks and take all precautions to make the job safe (Joint visit) Explain to the subordinates/worker the hazards of the job and precautions to be taken. All Engineering equipments are “FIT FOR USE” Provide PPEs, as written in Work permit Display the Work permit at work place Stop the job if the environment/situation changed during work (ask for new work permit as per new situation/environment) Continued… Role of Receiving Authority • • • Explain to persons executing the job, any specific permit requirements during the job. Ensure that job status at the end of the day / shift / time allocated is communicated to the issuer and permit is returned to the issuer with job status & mentioned closing time on it and signed by both Receiving & Issuing authority. Housekeeping of the area after the job. Work Permit System Take care of pre-requisites of Job • Isolation from Electrical Source of Energy • Isolation from Instruments Interlocks. • Isolations from Pressure Energy • Isolations from High Temperatures. • Removal of Hazardous / Toxic Materials (Process Isolation) Pre requisites of Job Process Isolation • • • • Breaking Flanges Inserting Blind Plates Double Block and bleed Closing / Tagging/ Chain Locks of Valves Instruments Interlocks • Make it ineffective. • Remove Fuses Electrical Isolation • Stop the machine first • Remove Breaker /Fuses (Rack out) and Tag the isolation Panel. • Pushing in of Emergency stop switch is not an approved method of Electrical Isolation Process Isolation Confirmation Through • Opening Vents. • Opening Drains • Through Pressure Indicators. • Cracking Flanges • De-contamination test through Laboratory Work Permit System Also takes care of POST job requirement • Area Housekeeping • Job status communication • Exchange of Work Permit copies. • Thoroughly checking of the area. • Electrical de-isolations. • Process de-isolations • Checking of smoldering after every 30 mins.(2 hours) Hot Work Permit Requirement  Any Hot Work activity which generates heat, friction or sparks(welding, cutting, grinding, heat treatment)  Opening or working electrical equipment in a hazardous area  Introducing equipment into a hazardous area which is not properly certified.  ALL require an air test for flammable atmosphere Hot Work Permits Requirements • • • • • • • • • To be accompanied by Cold Work Permit(depend). Depressurize/ Purge / Flush equipment for removal of any combustible materials and get checked LEL % in the area. Arrange trained Fire Watch. Make available Fire Extinguisher of suitable type. Ensure availability of all requisite fire fighting arrangements. Make area wet ( If required ). Make a tent ( If required ) Make available Fire Blanket. Check area after the job for any smoldering debris. Working At Height Requirement Working At Height 1-Area barricade. 2-Communication System & Observer. 3-Working platform as per standard provided with • Toe board • Guard rails , mid rails • Fixing of planks • Safety net(if required) • Provision of ladder for safe approach. 4-Ensure fall arresting (full body harness), mandatory at 2meter & above. 5-Inspection of scaffolding prior to start work.(craft inspector). Confined Space Entry Work Permit - Requirement Regulatory Requirement o OSHA 29 CFR 1910.146: Permit-Required Confined Spaces - (Jan 1993) o o o o o Identify Confined Spaces in Workplace Identify hazards in these spaces Identify procedures for controlling these hazards Train employees on confined space entry Keep records of compliance & training for all confined space activities What is a Confined Space? o Large enough that an employee can enter and perform assigned work o Has limited or restricted means for entry or exit o Not designed for continuous employee occupancy o Entry - includes insertion of a person’s head Examples of Confined Spaces  Vessels  –Reactors And tanks Boilers  Chimneys  Holes in the ground  Drains  Manholes  pits Principles for Safe CSE  Positive  Clean Isolation.  Ventilate So that entry can be achieved safely without the need for breathing apparatus Testing the Atmosphere  The person authorized to issue entry permits should specify in WRITING the requirements for atmospheric testing, covering gases to be tested for, points to be samples and testing frequency (minimum once every 4 hours). Atmospheric Hazards o Oxygen Levels - below 19.5 % or above 23.5% o Flammable/Explosive – exceeds 10% of Lower Explosive Limit (LEL) o Toxic Substances – exceed Permissible Exposure Limits (PEL) o Beware of the use of nitrogen Use of Tools in Confined Spaces  Ensure tools including lights and electrical items will be safe in the confined space especially if flammable vapors may be present(24 volts power supply only) Rescue Plan  This should be prepared BEFORE entry  Communications - outside help  Specify duties of stand-by person  – call for help, do NOT enter Rescue personnel must be trained and fit  Provision of lifelines, harnesses, stretchers, man hoists(if required),SCBA etc. to be confirmed. Before Approving Entry  Issuer should personally check all the isolations  Check the certificate of air analysis & others from Lab.  Ensure adequate standby provision.  Ensure there are back-up facilities to carry out a rescue Electrical Isolation Certificate Request for de-isolation will be generated by operation department. •Switch off circuit breaker/starter of desired equipment. •Rack out / withdraw complete switchgear assembly from panel. •Detached Fuses (if available in circuit) •Earthing switch is applied in case of MV circuit only. •No voltage, confirmation from circuit breaker output and load point by using standard VOLTMETER. •Apply the pad lock on Circuit breaker/MCC starter. •Use “DO NOT OPERATE” tags. Equipment will be handed over to operation department along with signed copy of isolation certificate Electrical De-isolation •Removal of “DO NOT OPERATE” tag. •Removal of pad lock from Circuit breaker/MCC starter. •Disconnect Earthing switch in case of MV circuit only. •Insert Fuses (if available in circuit). •Rack in switchgear assembly in panel. •Switch ON circuit breaker/starter of desired equipment. •Voltage Supply confirmation from circuit breaker output and load point by using standard VOLTMETER Equipment will be handed over to production department along with signed copy of de-isolation certificate Some Examples For Discussion False Information. Area safety lock on & tag on . All valves tagged. Isolation, depressurization, flushing & purging not required. •Nominated operator presence. False Information. •Lines disconnected & blinded •Safety lock on & tag on. •Vessel is hot. •Communication system False & Missing Information lock on & tag on. •After closing valves tagged. •No information about adjacent area safe for spark. •No information about explosivity lab test. •No information about the use of copper hammer. •Status of the job. •Closure time. •Plant shift Engineer signature at closing. Thanks – Any Question