Strategies & Effective Practices to Manage and Mitigate Hazards | AIChE

Strategies & Effective Practices to Manage and Mitigate Hazards

Scaffolding - Strategies & Effective Practices to Manage and Mitigate Hazards

Effective Practices to Manage and Mitigate Hazards

Develop a scaffolding plan to specify requirements for the design and management of the scaffold

  • At the start of the planning process, supply relevant information to the scaffold contractor to ensure an accurate and proper design process is followed.
  • Prior to installation, the scaffold contractor or scaffold designer can then provide relevant information about the scaffold.
  • Identify specific guidance or recognized standard to specify how scaffolding must be erected, dismantled and altered in a safe manner.
  • For scaffolds that fall outside the scope of a generally recognized standard configuration, the design should be such that safe erection and dismantling techniques can also be employed throughout the duration of the job.
  • Establish a process to address any proposed modification or alteration that takes a scaffold outside the scope of a generally recognised standard configuration should be designed by a competent person and proven by calculation.

Identify requirements for the erection of the scaffold

  • At the start of the erection process, inspection of all components should be performed and any substandard components removed from site.
  • During the erection process Platforms should be kept free of obstructions, unnecessary materials, projecting nails and other unnecessary tripping hazards (including uneven decking). Adequate space for workers to safely pass should be provided and maintained wherever materials are placed on platforms.
  • Scaffold operations adjacent to overhead power lines should b prohibited unless the regulatory conditions are satisfied:
  • At the completion of the erection process, the scaffold should be checked against the construction drawings. 

Identify requirements for the inspection of the scaffold

  • Inspection of scaffolding is a key safety element of the scaffolding process. 

  • Each company or organization should ensure scaffolds are properly designed erected and inspected by a certified inspector using an appropriate inspection check list or tagging system.  

  • A scaffold tagging system should be required to allow all users to observe the status of the scaffold.  

  • Scaffold tagging systems typically consist of a holder and inserts which are signed by the inspector.  These systems usually make use of a red tag meaning “Do Not Use”, a yellow tag meaning “recognized hazards exist and need to be controlled, but the scaffold may be used”, and a green tag meaning “Safe to Use” for the time period stated.  

  • Scaffold inspections are typically required to be performed each shift prior to first use 

Identify requirements for the safe use of the scaffold

  • Scaffolding is a temporary structure used to support a work crew and materials to aid in the construction, maintenance and repair of process plant and equipment and other man-made structures. Before working from a scaffold platform, the supervisor should ensure the scaffold tag is green and within date or yellow and within date (additional precautions may be needed with yellow tag scaffolds such as a fall protection harness and lanyard).  

  • During plant maintenance turnarounds and maintenance shutdowns large scaffolding structures may be in use with large number of employees on one structure at the same time.  The design should have been made with this loading in mind and include the additional weight of any materials on the scaffold.   

  • Large numbers of tools may be in use, and due to this, the importance of ensuring lanyards and tool tethers are applied correctly when working at height must be discussed at tool box talks and enforced by supervision. Preparations should be made for this during the planning phase prior to work. 

  • Barriers should be sufficient – and in line for the “cone of exposure” guidance provided in the dropped object prevention practices.  

  • Be mindful of coworkers working above and below you always, as well as others working on the scaffold. If you witness improper use on or around a scaffold you should stop what you are doing and notify the individual and communicate deficiencies to supervision.  

  • All work from a scaffold should be performed from the installed platform.  

  • When personal fall arrest systems are required for the scaffold you will be working on, thoroughly inspect the equipment for damage and wear. Anchor the system to a safe point (may require guidance from a fall protection competent person) that has the appropriate clearance for the shock absorbing lanyard or deceleration device to function properly. 

Identify requirements for the alteration of the scaffold

  • Employees working from a scaffold must be aware that any changes made to the scaffold design require re-inspection by a certified competent scaffolding inspector and invalidate the green “Safe to Use” scaffold tag.

Identify requirements for the use of a scaffold in a confined space

  • A confined space entry covers entry into a variety of workplaces which have limited access and or inadequate ventilation in which gases, vapors or physical hazards can present a risk to personnel. Including free flowing granular materials can engulf a person- e.g., sand, salt, grain; or steep sided stockpiled materials can collapse.
  • Water and other liquids can present a risk to personnel.
  • Scaffolders will have to support loads often in awkward positions, move heavy and unwieldy pieces of scaffolding poles and planks, carrying loads over uneven ground and up stairways or ladders, passing materials through vessel openings.
  • Avoid the need for hazardous manual handling, so far as is reasonably practicable.
  • Assess the risk of injury from any hazardous manual handling that cannot be avoided.
  • Reduce the risk of injury from hazardous manual handling, so far as is reasonably practicable. 

Identify requirements for the use of mobile scaffolds

  • Towers should be erected following a safe method of work. 

  • Design the tower so stability is maintained.  The design should account for possible use of sheeting, wind loads, and equipment loadings. 

  • Moving the tower requires reduction in height to approximately 4 meters or less (actual height reduction varies by jurisdiction), checking route for obstructions above and below 

  • No people or materials should be on the scaffold while it is being moved. 

  • Mobile scaffolds should not be moved until all attachments to equipment located on the ground have been disconnected.  Examples include disconnecting pneumatic hoses, electric cords, and ropes.  Failure to disconnect can result in a scaffold collapse during the move if the connections (e.g. – pneumatic hose) reach their length limit prior to the end of the move.   

  • Dismantle the tower using the Advance Guard Rail System (AGS).  AGS is an essential tool for any scaffolding crew especially those building and dismantling low level scaffolds where the available anchor points are insufficient for a deployed fall arrest system. It also offers scaffolders who are working at height an added level of security. The safety system provides a prefixed guardrail at working height before the scaffolder enters the working platform to install scaffold guardrails and toe boards. 

Identify requirements for the use of underhung scaffolds

  • The scaffold must be constructed and inspected by a competent person using an UNDERHUNG (SUSPENDED) SCAFFOLD FIELD INSPECTION checklist as set out in local regulations.
  • Any works over water are to be subject to the company “Permit to Work” system.
  • A fence or barrier must be provided to any structure or scaffold where there is a risk of persons falling from such structures into water.
  • Warning signs/notices are to be displayed stating hazards at site.
  • There is to be adequate lighting for the whole of the period of work. Lighting must be adequate for night work and must illuminate the immediate surrounding water surface.
  • A buoyancy aid, of a tested and approved pattern, is to be worn by all personnel working over water.

Identify requirements for the dismantling of the scaffold

  • Find sufficient space to neatly stack or store the components as they are removed from the scaffold.  

  • Ensure all people and movable obstructions are removed prior to dismantling 

  • Check to make sure truck access is available and has not been blocked.  

  • Wear proper safety gear.  

  • Begin dismantling at the top of the scaffold. 

  • Do not remove scaffold ties until the scaffold above the tie has been completely disassembled to the tie level. 

Read More
Line Opening - Strategies & Effective Practices to Manage and Mitigate Hazards

Effective Practices to Manage and Mitigate Hazards

Reduce risk by minimizing work on lines connected to equipment still in operation

  • Consider deferring line breaking to a future turnaround or outage when inventories of hazardous materials are at a minimum or eliminated.

Properly isolate line or equipment to be worked on

  • Use of manual valves.

  • Use of a double-block-and-bleed configuration to ensure manual valves are not leaking through.

  • Do not use control valves as an isolation device.

  • Do not work on line or equipment if there is an indication that isolation valve may be leaking through.

  • Lock-out/tag-out (LOTO) should be complete before line opening permit is issued.

Clean the line or equipment before opening

  • Develop procedures to clean or flush the line to minimize the amount of hazardous materials present.

Verify that the lines or equipment are drained and clean before proceeding with line opening task

  • Develop procedures to ensure that the lines or equipment are emptied, purged, flushed, drained, vented, isolated and locked/tagged as applicable to confirm the system is free from recognized hazards.

  • Verify that drains are not plugged giving a false indication that the line is empty.

Assure that personnel are not exposed to hazardous materials while draining the lines or equipment

  • Develop procedures to empty, purge, flush, drain, vent and properly isolate lines and equipment.

  • Verify that de-pressurization of lines or equipment and absence of material has been accomplished by opening vents and drains or by other means deemed appropriate.

  • Include proper disposal of hazardous materials in draining procedures.

  • For Line/Equipment Opening inside an operating building, extra caution may be needed to address potential asphyxiation hazards.

Treat initial line/equipment opening as if hazardous material is present

  • Require personnel performing line breaking to wear proper PPE for the hazardous material that is normally in the line.

  • PPE should remain in place until personnel verifies that the line is empty and clean.

  • Loosen the flange bolts away from you first to minimize exposure in case of a release.

Identify location of each line or equipment opening

  • Identify the location of line opening by marking on the pipe.

  • Positively identify location of each line opening at the time of on-site inspection.

  • During on-site inspection verify that person performing the work or accepting the permit knows the location of the line opening.

  • Use the P&ID to determine all isolation/blinding or block/bleed valve locations.  Develop an Isolation/blinding/block/bleed list for the job. 

Identify access issue or congestion in the area

  • Assure adequate access to the location of the line opening is available.

  • Identify any congestion issues and possible additional hazard (i.e. ¼” valves that could be bumped open on another line).

Use special precautions for opening a vent line or flare header

  • If possible, make certain that any equipment connected to the vent header is down and isolated.

  • If a vent header is used as a relief device vent develop procedures to make sure that pressure in upstream equipment is monitored and equipment is shutdown before pressure reaches the relief device setting.

Avoid sparks if the line must be cut

  • Obtain Hot Work permit.

  • On lines or equipment which may have contained flammable and/or toxic liquids or gases, test with a properly calibrated combustible gas indicator initially and intermittently during work.

  • Use cold cutting methods to cut a line that contained flammables.

  • Consider purging the line with nitrogen to minimize possibility of fire.

  • Connect both side of the area to be cut with ground straps before cutting to minimize ignition potential.

Analyze hazards and identify means of control

  • Survey the worksite and look for potential sources of ignition if the line opening involves flammable materials.

  • Ignition sources could include hot equipment surfaces, vehicles or hot work being performed in the area, including above and below.

  • Ensure that where work is performed on elevated piping or equipment, the area below the work will be barricaded and splash pans/spark containment provided as needed.

Understand operational status

  • If line or equipment is isolated with a single valve, consider the possibility of leakage.

Recognize changes in process conditions

  • Line or equipment openings that last over several hours or days need to be secured by installing blind flanges or in-line blinds to prevent unexpected releases.

  • Treat disconnecting a blind flange as a line opening.

Ensure resources to adequately assess safe work activities

  • Time pressure and/or task complexity on authorizing personnel to get permits issued can compromise the safety process through the adoption of a “seems OK to be” process.

  • Assure that there are enough resources to properly inspect the line opening site and positively identify the location of the line opening before permit is issued.

Create safe environment

  • Require proper PPE to protect personnel during initial line breaking.

  • Personnel breaking lines must place themselves in a defensive position to avoid a spray of liquid or release when attempting the initial opening.

  • Identify location of the nearest safety shower and eye wash to be used in case of an emergency.

  • Install blind flanges on lines in hazardous service when equipment is removed for maintenance.

Ensure that all workers are competent to execute their responsibilities

  • Provide training to all personnel in Line/Equipment breaking policies and procedures.

  • Ensuring contractors have required craft qualifications.

  • Closely supervise all contractors to ensure they are aware of all hazards and how to respond to emergencies.

Continuous monitoring of the envi-ronment; stopping work if hazardous material is detected in the line

  • Line or equipment opening work should be stopped if presence of hazardous material is detected.

  • Hazard evaluation should be completed to determine how the work should proceed or if it should be postponed.

Communication is essential between the control room, the Operating personnel and the people conducting the work

  • Communication with the control room at all times is essential.

  • If an emergency alarm is sounded, all line opening work must cease immediately.

  • Area should be re-inspected and line opening permit re-issued after emergency is resolved.

Read More
Field Review of Permits - Strategies & Effective Practices to Manage and Mitigate Hazards

Conducting initial field inspection

  • Ensure that the equipment that will be worked on is identified/tagged prior to issuing the SWP. 
  • Confirm that the location is safe and does not require additional measures to control hazards. 
    • Safe access is available for the work crew 
    • Area is safe to move objects required for execution of the job 
    • Escape routes are clear 
  • Identify the requirements for decommissioning procedures, blinding diagrams, and isolation lists. 
  • Confirm that there are no routine or non-routine vents present in the area that could impact the work crew.
  • Confirm that there are no leaks or abnormal situations noticed in the vicinity of the work location. 
  • Checklists for all related SWPs such as Excavation, Hot Work, Work at Height, and Confined Space Entry, are available and completed, including signatures/initials. 

Conducting field inspection prior to authorizing the permit

  • Ensure that the controls that are listed in the permit, task risk assessment, Job Safety Analysis (JSA), procedures, blinding diagrams or in checklists are executed as intended. 
  • Confirm that all energy isolations are completed, verified, and keys for the lock out are available with the work crew. 
  • Verify that there are no additional hazards (spills, leaks) present at the time of field inspection than the hazards for which controls are in place.
  • Ensure that the number of persons in the area that could be impacted are minimized and are consistent with the number considered in the risk assessment. 
  • Confirm that there are no simultaneous operations (SIMOPS) planned around the job location during execution of the Safe Work Permit. 
  • Verify that all tools, material, fire and gas detectors, communication tools and personnel protective equipment (PPE) required for safe execution of the jobs are available and meet the required specifications. 
  • Ensure that the work crew has been briefed and understood the hazards and controls. 
  • Verify that the work crew is competent and has all the necessary skills to perform the job safely. 
  • Verify that the frequency of field reviews during execution of the job has been established.  
  • Ensure that any outside contract crews working in the area who are not associated with the permit in question are informed of the work to be done. 

Conducting field inspection during execution of Safe Work Permit

  • Field inspections are carried out by the Permit Issuer in the presence of the Permit Receiver (Acceptor) at the frequency specified in the SWP. 
  • Ensure area is safe and permits are extended by authorized permit roles 
  • Ensure that no additional hazards exist beyond those being managed by the permit. 
  • Ensure that the work crew is available, is not fatigued and they have all equipment and personnel protective equipment (PPE) necessary to complete the work safely, even in adverse ambient conditions. 
  •  Ensure that the work crew is taking breaks as specified in the risk assessment 
  •  Verify that all necessary and relevant checklists are being filled and records maintained. 
  • Ensure actions are taken to promptly correct any problems or deficiencies observed in this inspection. 

Conducting field inspection after completion of execution of Safe Work Permit

  • Verify that the work has been executed to the relevant engineering standards and satisfies the requirements of those standards.   
  • In addition, ensure that:  
    • The work site is restored, and all tools and temporary equipment have been packed up. 
    • Combustible materials, molten metal pieces after gas cutting, hot welding rods, hot surfaces after welding, and metal cuttings have been allowed to cool safely and are then removed. 
    • All electrical work is per codes and requirements.  Ensure that temporary electrical junction boxes or extension boards with live electric supply have been de-energized and removed.  
    • Contaminated hoses used for decommissioning have been decontaminated and moved to a safe location. 
    • Uncontaminated/unlabeled equipment is removed from job location. 
    • Area housekeeping is adequate for safe re-start of equipment. 



Structured field review checklist

  • Gather data to develop metrics or key performance indicators (KPIs) to inform management of strengths and weaknesses in the system and to provide recommendations for where to place resources to improve the process. 

     
Read More
Equipment Identification - Strategies & Effective Practices to Manage and Mitigate Hazards

Proper equipment tagging

  • Periodically complete a site survey to ensure that the Process and Instrumentation Diagram (P&ID, also known as a flowsheet) accurately depicts plant equipment, valves and instruments as installed in the facility. 

    • Ensure that all equipment, valves, and instruments are correctly labeled as shown on the P&ID 

    • Add or correct labels for any equipment, valves, or instruments that have incorrect or missing labels 

  • Ensure equipment involved in a job is identified / tagged prior to issuing Permit to Work (PTW) 

  • Pipelines are color coded according to standard practices (please see references) 

  • Proper tagging of emergency response equipment verified by Site HSE personnel 

  • Tagging / marking of the capacity of tanks/storage vessels helps avoid overfilling incidents  

Stopping or discontinuing work if incorrect tagging is identified

  • Authorize personnel to stop any Permit to Work (PTW) activities if any incorrectly identified equipment is found.

Regular inspection and review of tagging/identification

  • Periodically scheduled inspections / reviews for proper Equipment Identification can be established based on the hazardous consequences, the Risks assessed, and prior incidents.
  • Establish and periodically audit procedures for the tagging of new spares, equipment, and materials.  

Specific procedures are required when loading or unloading chemicals into storage tanks 

  • Understand potential hazardous interactions among different materials that are unloaded into storage tanks at your facility.  

  • Always check all the documentation and labeling on incoming shipments of raw materials to confirm that the material being received is as expected. 

  • Follow plant procedures for identification of incoming raw materials and for unloading those materials. 

  • Make sure that all the piping and equipment in the raw material unloading areas are clearly labeled. Also, there should be no connections between pipes serving different tanks containing incompatible materials. 

  • If the raw material unloading area has confusing piping, or incompatible materials are unloaded in locations near to each other, inform management about the issue so that improvements can be made. 

    • If supplier or transportation company truck drivers unload materials into storage tanks at your plant, make sure they are familiar with your unloading facilities and can ensure that they unload materials into the correct tank. 
Read More
Hot Tapping - Strategies & Effective Practices to Manage and Mitigate Hazards

Site specific written down procedure for hot tapping

  • Even though there are API codes and guidelines available for conducting welding/drilling on live systems, each facility is unique. It is recommended that each site develop an exhaustive procedure for carrying out hot tapping on live equipment at their premises.  

  • The procedure should detail the technical requirements and the responsibilities of the various agencies/personnel involved in the execution of the job  

  • The procedure should indicate fluids used at the facility for which hot tapping is prohibited.  As an example, fluids that can cause stress corrosion cracking in metals should not be considered for hot tapping.  

Hot tapping as the last option

  • Taking a branch connection or performing maintenance by welding on live system should be the last option for any operator considering the serious hazards posed by the activity.

  • All options available other than welding on live equipment/pipelines should be evaluated and documented.

  • Considering the serious hazards, a well-documented approval matrix should be put in place for authorization of each of the hot tapping jobs. 

Hot tap design

  • A request for welding on live system should be created. The request should include, as a minimum, parameters like:

a)    Size and actual thickness of the hot tap location 

b)      Operating pressure and temperature

c)    Fluid characteristics (flammability, toxicity, corrosivity) 

d)      Velocity / flow

e)      Metallurgy

  • Based on the request, the modification to the system should be designed per relevant national/international codes and standards. The site/facilities engineering standards should be followed while designing the modification.  

  • The design engineer should be informed that the branch connection should be done by Hot Tapping. 

  • Design engineer should design the nozzle reinforcement to meet the machine loads during the drilling operations.  

  • Design engineer should do a field visit to check the location where the welding/drilling is to be performed. 

  • Design engineer should discuss the hot tap procedure with service providers/contractors entrusted with the job of welding/drilling on the live system 

  • Design should be validated by persons considered competent.  

  • Design should include a testing requirement for the modifications. 

Feasibility for safe hot tapping

  • Feasibility of hot tapping should be done by a team from the process plant facility and the service provide/contractor.
  • A preliminary risk assessment should be done to check whether the Hot Tapping can be done safely at the specified location in the process unit.
  • The service provider, based on their experience, will provide inputs on safe execution of the hot tapping.  All relevant design information (as listed above) should be shared with the contractor in order to make an accurate determination of feasibility. 

Making sure that metallurgy of the existing pipe is suitable for hot tapping

  • Hot tapping is normally only done on carbon steel piping and equipment.
  • Hot Tapping is not carried out on ferritic alloy steels where special welding requirements like preheat, post heat and post weld heat treatment are required.
  • Hot Tapping on metallurgies other than carbon steel should need special procedures and is outside the scope of this document.
  • Positive Material Identification (PMI) on the pipeline / equipment is necessary where hot tapping is to be done, to ensure that the material is indeed carbon steel and there is no mix up during the original construction.
  • If there are welding joints that intersect hot taps, then PMI should be done on the weld joints also
  • Hot Tap welding should not intersect electric resistance seam weld in the pipe. 

Inspect the existing weld joints that intersects hot tap weld joint for integrity

  • Hot Tap should be avoided on existing weld joints. The location should be chosen in such a way that Hot Tap welding does not interfere with the existing weld joints.
  • Longitudinal seam weld joints should be identified by suitable in-situ etching methods.
  • If Hot Tap cannot be avoided without intersection, then the interfering weld joint should be volumetrically inspected (either UT or RT) to make sure that there are no defects in the weld joint that can lead to burn through during hot tap welding. The UT or RT should be done for the purpose of hot tapping and certified.  
  • The area over which hot tapping is to be done should also be checked by the Mechanical Integrity inspector to detect sub-surface defects if any.

Making sure that the metal thickness at the hot tap location is adequate

  • The location where thickness is to be measured should be hard punched and this should not be changed without consent from the site inspectors.
  • Thickness should be measured by devices that work based on Ultrasound. Any other method of measurement needs to be approved by owner inspector.
  • The thickness should be exactly measured at the location where the welding is expected to be done. It is recommended to measure thickness over a 2” band. Recommended minimum thickness for hot tapping is about 5.0 mm.
  • A critical review of the measured thickness may be necessary if:  

    1. Hot tapping welding is planned on systems with thickness close to the minimum thickness of 5.0 mm 

    2. Hot tapping is being considered on corroded pipelines. (e.g. Nominal thickness is 10 mm and measured thickness is close to minimum required thickness of 5.0 mm) 

    3. Hot tapping is planned on a system which has undergone a fitness for service evaluation 

  • High Temperature thickness measurement should be cross-verified adequately to ensure that the measured readings are dependable 

Making sure that the metal where hot tapping is being done meets the hardness requirements

  • It is recommended to measure and certify hardness to be less than 200 BHN (Brinell Hardness Number). Higher hardness material can crack during welding.   Higher hardness can also cause problems during drilling of coupons.  

Maintaining fluid flow during hot tap operations

  • Hot tapping operations are considered safe based on the fact that molten metal during welding solidifies and cools to less than about 400 deg C very quickly. This is necessary to achieve the mechanical properties able to withstand the system pressure. A positive flow in the pipeline helps in conducting the welding heat away and cooling the molten metal quickly.
  • A positive flow should be ensured during the full cycle of hot tapping operations.
  • The greater the thickness reduces the dependency on flow to cool the metal. However, flow has to be maintained.
  • Operating crew will identify a direct quantitative measurement of fluid flow in the line where hot tapping is being done. The calibration of flow meter should be ensured.
  • If the flow measurement is not available for direct determination in the line where hot tapping is being done, an indirect method of ensuring flow should be established. This should be validated by competent personnel at the facility.

Ensure welding procedures are in place

  • Hot tap welding should be done as per an approved WPS.
  • Welders should be qualified for the material and thickness.
  • Based on the thickness of the metal, heat input during welding has to be controlled to make sure that metal does not get over heated.
  • Welding heat input is dependent on the welding speed. Based on the maximum heat input allowed, welding speed should be calculated.
  • The welder should be trained on a mock up piece to comply with the welding speed requirements.

Ensure that the new materials are used in fabrication of hot tap connection are as per specification

  • All the materials like pipe, reinforcement pads and welding consumables should be checked by Positive Material Identification tools to make sure that there is no mix up.

Test the integrity of the hot tap nozzle before fixing

  • The hot tap nozzle should be welded to the flange and this spool should be hydro-tested at the required values per the drawings and appropriate codes. This should be done prior to welding the nozzle on the existing equipment / pipeline by hot tapping. 

Switch off Cathodic protection

  • Cathodic protection can sometimes affect welding operations in pipelines. Ensure the same is switched off.

Have a risk assessment done for the complete hot tap job

  • Maintenance, Inspection and Operations crew on site should meet with the contractor and prepare a risk assessment for conducting the hot tap job safely.  

  • The evaluations/inspections that were completed to certify the pipe / equipment as fit for hot tapping shall be shared with the contractor performing the work. 

  • Inform the crew of the hazards of the fluid flowing through the pipe 

  • The risk assessment should include a contingency plan in case of a mishap during hot tapping 

  • Ensure availability of communication between the hot tap crew, supervisors and control room for emergency actions that may be required.  

  • Fire department should be kept informed for responding in case of emergencies 

  • Ensure that any scaffolding or platform, if erected for the hot tap job, is large enough for personnel to back off from the work area.  Plan for alternate exits from the scaffold / platform. 

  • Make sure that escape routes are clear.  

  • Ensure that minimum personnel are present close to the hot tap location while welding is in progress.  

  • Ensure enough ventilation and lighting in the work area. 

  • Make arrangement for gas monitoring of the hot tap location continuously until welding is complete, approximately 30 minutes following completion of the work.  

  • Prepare a briefing/toolbox talk to all the crew involved on the hot tap jobs regarding the safety and emergency procedures 

Stiffening of parent pipe

  • For large size hot tapping typically greater than 20”, there is always a possibility of the coupon springing back when the coupon cutting is complete. If spring back happens, coupon removal can be difficult. Consider installing welding stiffeners on the coupon to be cut prior to drilling and cutting.

Test the integrity of the hot tap nozzle after welding

  • The hot tap nozzle should be pressure tested after welding is complete. During this pressure test, the parent pipe or part of the equipment on which the nozzle is welded is subjected to an imposed pressure. Hence, this test pressure has to be calculated by the design engineer and provided to the hot tapping contractor. If pressure testing is done above this calculated value, the parent pipe can buckle inwardly. The larger the branch of the hot tap, the higher the risk of buckling.
  • The testing medium should be selected based on the temperature of the fluid flowing through the pipeline / equipment. 

Check and certify the isolation valve

  • The isolation valve to be installed on the hot tap flange should be hydro-tested in the shop prior to installation to ensure seat sealing. The gland packing should be changed prior to test to make sure that there are no leaks during the pressure test and subsequent hot tapping operations.

Test of hot tap drilling machine

  • Check the drilling machine maintenance records / date.
  • Check the hydrotest certification of all pressure parts of the drilling machine.
  • Check the hydraulic hoses used in the drilling machine visually and ensure that they have been pressure tested.
  • The pressure gages installed on the drilling machine must be calibrated and certificate should be valid.
  • The packing used in the drilling machine should be new and compatible to the operating fluid at the operating temperature of the fluid. 

Check and certify the gasket joints in the hot tap connection

  • Do a pneumatic leak test and make sure that gasket joints are not leaking / passing. Both the gaskets between valve and nozzle and the gasket between valve and the drill machine should be tested.
  • Check for gland leaks during the leak test.

Make sure that the drilling cavity is functional

  • When the pilot drilling is done, the hot tap nozzle and the valve above will become pressurized. The vent valve should be in operation to safely vent at various stage of drilling operation. 
 
Read More
Energy Isolation - Strategies & Effective Practices to Manage and Mitigate Hazards

Effective Practices to Manage and Mitigate Hazards

 

Reduce risk by minimizing work on lines or equipment still connected to operating portion of the process unit

  • Consider deferring work activities requiring line or equipment opening to a future turnaround or outage when inventories of hazardous materials are at a minimum or eliminated.
  • Consider deferring work activities on energized electrical circuits to a future turnaround or outage when these circuits can be properly de-energized.
  • For batch processes schedule maintenance and repair activities to avoid running cycles

Properly isolate chemical and thermal energy in lines or equipment to be worked on

  • Use blinds or line breaking as a means of isolation, if possible.
  • Use double block and bleed for isolation of lines or equipment handling hazardous or hot materials.
  • Do not use control valves for isolation.
  • Do not use check valves for isolation
  • Verify that isolation valves are properly locked so they cannot be operated.

Properly isolated kinetic energy before starting work on the equipment

  • Lock-out the energy source to the rotating equipment to be worked on.
  • Verify the correct energy source is locked-out by trying to start de-energized equipment in the field.
  • Verify that rotating equipment has coasted to a full stop before starting work activities.

Properly isolated electric energy when working on electrical circuits

  • All electrical isolation activities should only be performed by electrically qualified personnel and with the proper PPE for electrical isolation.
  • Disconnect and lock-out energy sources.
  • Control circuit devices, such as push buttons, selector switches, and interlocks, should not be used as the sole means for deenergizing circuits or equipment. Interlocks for electric equipment should not be used as a substitute for lockout and tagging procedures.
  • Stored electric energy which might endanger personnel should be released. Capacitors should be discharged and high capacitance elements should be short-circuited and grounded, if the stored electric energy might endanger personnel.
  • Verify that the proper energy source is locked-out before starting work activities

Properly isolated hydraulically operated equipment

  • De-energized and lock out hydraulic pumps.
  • Verify that correct equipment is de-energized by testing in the field.
  • De-pressure hydraulic systems to assure that potential stored energy is not release during work activity.

Review the worksite for potential stored energy releases due to gravity

  • Support or tie off any piping or equipment that may move (fall or swing to the side) when it is disconnected.
  • Use blocks or chains to assure that equipment such as top parts of casting molds or presses do not fall due to gravity during work activities.

Create a safe working environment

  • Assure that personnel performing the work install their locks on the equipment (or on a lockbox, if used) and verify that equipment is properly de-energized.
  • In every location that the installation of a lock is specified, there should be an installation of a tag
  • Ensure that an equipment specific Lock-Out/Tag-Out procedure is available and used.
  • Ensure an isolation log is developed, is adequate and is updated (consider marking the P&IDs as well). 
  • Require proper PPE to protect personnel during initial line breaking.
  • Personnel breaking lines must place themselves in a defensive position to avoid a spray of liquid or release when attempting the initial opening.
  • Identify location of the nearest safety shower and eye wash to be used in case of an emergency.

Energy Isolation / Lock Out / Tag Out is often used in conjunction with other SWP activities such as Line Opening, Hot Work, and Confined Space Entry.  Please read those SWPs for details  related to those activities.  Energy Isolation actions related to these other SWPs might include the following.

  • Line Opening:  Verify that de-pressurization of lines or equipment and absence of material has been accomplished by opening vents and drains or by other means deemed appropriate.
  • Line Opening:  Assure that drains are not plugged giving a false indication that the line is empty.
  • Energy Isolation of flammable gas lines
  • Confined Space Entry:  Energy isolation of lines containing asphyxiants (e.g. – Nitrogen) or toxic gases.

Identify access issue or congestion in the area

  • Assure adequate access to work site is available
  • Identify any congestion issues and possible additional hazards (i.e. quarter-turn valves that could be bumped open on another line)
  • Apply Lock-Out/Tag-Out/Try procedures to any additional hazards that are identified

Analyze hazards and identify means of control

  • Ensure that where work is performed on elevated piping or equipment, the area below the work will be barricaded and splash pans provided as needed.
  • Identify all potential sources of hazardous energy and develop proper Lock-Out/Tag-Out procedures to de-energize

 

Understand operational status

  • If line or equipment is isolated with a single valve, consider the possibility of leakage.

Recognize changes in process or work conditions

  • A permit for Energy Isolation / Lock Out / Tag Out activities should be re-issued at the beginning of each shift.
  • New personnel that are added to a work crew should install their locks prior to performing any work.

Ensure resources to adequately assess safe work activities

  • Pressure on authorizing personnel to get permits issued can compromise the safety process through the adoption of a “seems to be OK” process.
  • Specify degree of operator presence and inspections required which should be consistent with the magnitude of the identified hazards.

Ensure that all workers are competent to execute their responsibilities

  • Provide training to all personnel (including contractors) in Lock-Out/Tag-Out policies and procedures.
  • Ensure contractors have required craft qualifications and lock-out/tag-out training.
  • Closely supervise all contractors to ensure they are aware of all hazards and how to respond to emergencies.

Communication is essential between the control room, the Operating personnel and the people conducting the work

  • Communication with the control room at all times is essential.
  • If an emergency alarm is sounded, all work must cease immediately and the work area made safe. 
Read More
Excavation - Strategies & Effective Practices to Manage and Mitigate Hazards

Effective Practices to Manage and Mitigate Hazards

 

Defer excavation to a future turnaround or outage

  • When the risk of excavation is considered unacceptable, consideration should be made to defer it until the plant is in a safer condition.
 

Identify all underground utilities and pipelines

  • All utilities and lines should be properly identified and appropriate parties notified before beginning any digging or clean-up work.
 

Prevent spoil falling back into excavation

  • Spoil piles should be at least 0.6 m (2 ft.) from the edge of the excavation.
 

Erecting scaffolding in a safe location

  • Scaffold bases should be at least 1.5 times the depth of an excavation away from the edges of the excavation (including trenches).
 

Protecting hidden pipes and cables

  • Mechanical excavators should not be used within 3 m (10 ft.) of any pipes, cables, or other obstructions.
 

Effect of plant and vehicles

  • Do not park plant and vehicles close to the sides of excavations. The extra loadings can make the sides of excavations more likely to collapse.
 

Preventing excavation collapse

  • Heavy equipment should not be operated within 1.8 m (6 ft.) of any excavation.
  • Cranes should not be operated closer than the depth of the excavation.
 

Recognizing hazards

  • A qualified person should make daily inspections of excavations using the approved checklist prior to the start of the work shift.
 

Protecting the excavation

  • Guardrails or barricades, as necessary, should be established a safe distance from the excavation to protect individuals and mobile operating equipment above the excavation, or if the excavation is left unattended overnight.
 

Restricting access to excavation

  • No personnel should be permitted in the excavation or trench when power equipment is being used to perform the excavation.
 

Identifying excavation

  • Blinking warning lights should be used at excavations at night where there are personnel or vehicle movement.
 

Preventing authorized access

  • Only authorized personnel should enter the excavation.
 

Keeping excavations dry

  • Ensure there is no water seepage into the excavation
 

Ensuring safe atmosphere for working

  • Qualified personnel should test and monitor the atmosphere while personnel are present (e.g., combustibles, toxic gases, or low O2).
 

Providing safe egress and access

  • Ladders or other means of access should be provided every 7.5 m (25 ft.) in all occupied excavations, extending a minimum of 1 m (3 ft.) above the top of excavation wall.
 

Preparation for an emergency rescue

  • Emergency rescue equipment should be immediately available for excavations considered as confined spaces.
 

Recognize changes in process conditions

  • Excavation permits that extend over many hours should be reevaluated to ensure the surrounding area and plant conditions have not significantly changed, and that the controls detailed on the permit remain valid.
 

Ensure resources to adequately assess safe work activities

  • Time pressures and/or task complexity stresses placed on authorizing personnel to get permits issued can compromise the safety process through the adoption of a “seems OK to proceed” mindset. These situations are associated with a higher frequency of process breakdowns and the introduction of additional risks.
  • Specify degree of operator presence, consistent with magnitude of identified hazards.
 

Use hazardous area classification to prohibit specific activities and specify classification of equipment usage

  • Hazardous zoning of the site enables the specification of the type of equipment allowed within each area.
  • Only electrical equipment meeting the requirements of the hazardous area classification should be used in those areas.  This can include, but is not limited to intrinsically safe equipment.
 

Use of ventilation to bring fresh air into excavation

  • Make sure excavation is not enclosed.
  • Ventilate excavation to ensure hazardous fumes do not collect.
 

Use of bonding and grounding to ensure that static electricity does not accumulate and cause a spark when disconnecting pipes in an excavation

  • Understand what processes and equipment are subject to static electricity.
  • Install grounding and bonding cables to applicable equipment.
  • Inspect grounding and bonding cables prior to performing excavation.
  • Replace grounding and bonding equipment if damaged or compromised.
 

Continuous monitoring of the environment; stopping work if combustible gas levels are detected

  • Gas testing should be carried out by certified gas testers.
  • Gas test equipment should be periodically calibrated and tested before use.'
  • The authorized gas tester should instruct the work party on the type of continuous gas monitoring (audible alarm preferred) being used and ensure they know how to respond to rising % LEL levels.
  • Work should commence no later than 1 hour after the initial gas test is recorded.
  • If work is suspended for any period, another gas test should be performed before the excavation permit is reissued and work recommences. 
 

Clear identification of equipment on the plant

  • Ensure that the equipment to be worked on is correctly identified and labelled so that it will be correctly isolated and purged.  
 

Isolate, depressurize and purge equipment to be worked on as well as other potential nearby combustible fuel sources

  • Lock Out / Tag Out should be linked to the permit and a necessary precursor for commencing work.
  • Good practice is to demonstrate the equipment is energy- and gas-free before excavation commences.
 

Use of dedicated worker on standby with communication capability in the event of an emergency

  • A dedicated standby person should be part of the work party for any excavation.
 

Ensure that all workers are competent to execute their responsibilities

  • Provide training to all personnel in excavation policies and procedures.
  • Ensuring contractors have required craft qualifications.
  • Closely supervise all contractors to ensure they are aware of all hazards and how to respond to emergencies.
 

Ensure excavation equipment is in good condition

  • Grounding of electrical equipment should be within the excavation area in case of grounding sparks.
 

Communication is essential between the control room, the operating personnel, and the people conducting the work

  • Communication with the control room at all times is essential.
  • If an emergency alarm is sounded, all excavation work must immediately cease.  All gas checks must be repeated before work can recommence following an emergency alarm.
 
Read More
Equipment Filling and Mixing - Strategies & Effective Practices to Manage and Mitigate Hazards

Hazard Identification

  • Identify chemicals that are incompatible if mixed.
  • Identify places/opportunities when incompatible chemicals may be wrongly interacted and manage their confinements.
  • Avoid using the incompatible chemicals, if possible, in the process as part of Inherently Safer Design. Use alternate compatible chemicals.
  • Maintain chemicals and materials interaction matrix. 
 

Human Factors – Design of Chemical Transfer Equipment

  • Isolate physically or using distance to separate fill lines to lower risk of incorrect connections.
  • Use hose couplings and fill line connections with uniquely shaped and color-coded fittings for each chemical.
  • Identify each chemical by unique labelling and identification tag.
 

Automation and Remote Shutdown

  • Install or configure interlocks and mitigation measures to maintain safe operations during chemical unloading activities.
  • Install fume detection, extraction and destruction system in chemical warehouse for mitigating event.
 

Facility Siting and Design of Occupied Building

  • Evaluate building design and ventilation systems near chemical unloading stations and chemical storages to protect the occupants in the event of spill or chemical reaction.
 

Segregation of Storages

  • Separate locations for storing incompatible materials.
  • Dykes or bunds around liquid chemicals storages.
 

Segregation of Collection and Effluent Pits

  • Maintain separate collection pits for draining of chemicals that may interact and have hazardous consequences.
  • Examine the draining systems for avoiding possible mixing of incompatible chemicals.
 

Emergency Response

  • Access to availability of Emergency Response equipment.
 
Read More
Temporary Instrumentation and Controls Bypass - Strategies & Effective Practices to Manage and Mitigate Hazards

Reduce risk by elimination of bypass events.

• Select safeguards that would not typically need bypassing for start-up.

  • Automate the temporary inhibit of safeguards, following required permissives, during start-up to eliminate need for manual bypassing.  Include a timing function that automatically reverts the interlock to full operation after a specified period of time.

• Avoid protection strategies that would use the same safeguard device in conflicting states (e.g., one hazardous event requires a valve to close while a different hazardous event would require the same valve to be opened).

• Use redundancy in safeguard architecture so that each malfunc-tioning safeguard device can be repaired without defeating the entire safeguard function.

Use controlled and auditable means of access restriction for bypasses.

• Install locks on root valves used to bypass devices and control ac-cess to the keys.

• Use passwords to control bypasses of programmable devices.

Manage risk during the bypass of a safeguard.

• Identify and implement compensating measures sufficient to address any risk gap created by the bypass.

Design safeguards to be tested during a turnaround or outage.

• Use redundancy in safeguard architecture so that planned testing can be performed during facility outages when process equipment will be isolated in an inherently safe state.

Understand operational status. Recognize changes in process conditions.

• If the plant, or a portion thereof, is unstable and a potential to initiate a hazardous event exists, caution should be exercised be-fore issuing Bypass permits.

Ensure resources to adequately assess safe work activities.

• Time pressure and/or task complexity stresses placed on authoriz-ing personnel to get permits issued can compromise the safety process through the adoption of a “seems OK to proceed” mind-set. These situations are associated with a higher frequency of process breakdowns and the introduction of additional risks.

• Specify degree of operator presence, consistent with magnitude of identified hazards.

Clear identification of equipment on the plant

• Ensure that the equipment to be worked on is correctly identified and labelled so that only the intended device will be bypassed.  

Use of Bypass permits to manage activities, specify controls, manage simultaneous operations and communicate to others.

• Avoid using bypass procedures simultaneously with non-routine process changes.  

Ensure that all workers are competent to execute their responsibilitiesEnsure compensating measure equipment is in good condition

• All automation devices used in pre-identified bypass compensat-ing measures should be included in the facility automation asset integrity program.

• Any automation device used in a bypass compensating measure that is identified and approved immediately prior to the bypass event should be inspected and verified to be properly functioning prior to the bypass being used.

Ensure compensating measure equipment is in good condition

(Compensating Measure - planned and documented means for managing risk during periods of process operation with known failures or problems, resulting in increased risk)

  • All automation devices used in pre-identified bypass compensating measures should be included in the facility automation asset integrity program.
  • Any automation device used in a bypass compensating measure that is identified and approved immediately prior to the bypass event should be inspected and verified to be properly functioning prior to the bypass being used

Communication is essential between the control room, the Operating personnel and the people conducting the work.

• Communication with the control room at all times is essential.

• If the compensating measure for bypass use is dependent on ad-ministrative control (e.g., local monitoring for hazardous condition with manual control response), the administrative control proce-dure should include clear instructions on the immediate action(s) to take should an emergency alarm be sounded

Read More
Confined Space Entry - Strategies & Effective Practices to Manage and Mitigate Hazards

Effective Practices to Manage and Mitigate Hazards

 

Reduce risk by minimizing confined space entry work on vessels connected to equipment still in operation

  • Consider deferring confined space entry to a future turnaround or outage when inventories of hazardous materials are at a minimum or eliminated.
 

Properly isolate line or equipment to be worked on

  • Use blinds or physical disconnects.
  • Do not use valves as isolation devices.
  • Lock-out/tag-out should be completed, including moving parts (i.e. agitators) before confined space entry permit is issued.
 

Clean the equipment before opening

  • Develop procedures to clean or flush the equipment to minimize the amount of hazardous materials present.
 

Verify that the equipment is drained and clean before proceeding with confined space entry task

  • Develop procedures to ensure that the equipment is emptied, purged, flushed, drained, vented, isolated and locked/tagged as applicable to confirm the system is free from recognized hazards.
  • Assure that drains are not plugged giving a false indication that the equipment is empty.
 

Assure that personnel are not exposed to hazardous materials while draining the equipment

  • Develop procedures to empty, purge, flush, drain, vent, and properly isolate lines and equipment.
  • Verify that de-pressurization of lines or equipment and absence of material has been accomplished by opening vents and drains or by other means deemed appropriate.
  • Include proper disposal of hazardous materials in draining procedures.
 

Treat initial line/equipment opening to isolate equipment for confined space entry as if hazardous material is present

  • Require personnel performing line breaking to wear proper PPE for the hazardous material that is normally in the line.
  • PPE should remain in place until personnel verifies that the line is empty and clean.
  • Loosen the flange bolts away from you first to minimize exposure in case of a release.
 

Identify location of each isolation point for confined space entry

  • Identify the location of needed blinds or disconnects by marking on the pipe.
  • Positively identify location of each line opening at the time of on-site inspection.
  • During on-site inspection verify that person performing the work or accepting the permit knows the location of the line opening.
  • Ensure a blinding list is adequate and updated (consider marking the P&IDs as well).
 

Properly lock-out equipment

  • Assure that any rotating equipment such as agitators are properly de-energized and locked out.
 

Eliminate exposure from radiation devices

  • Shutter on radiation devices must be closed and locked.
  • Verify absence of radiation hazard by using proper equipment and properly trained industrial hygiene personnel.
 

Eliminate possibility of engulfment if the confined space is a trench or a pit

  • Slope side s of the excavation.
  • Properly shored up sides to prevent collapse.
  • Use trench shields or trench boxes.
 

Identify access issue or congestion in the area and develop a rescue plan with proper equipment in place

  • Assure adequate access to personnel in the confined space.
  • Identify rescue equipment and develop rescue plan.
  • Assure rescue equipment is available and set up per rescue plan.
 

Properly test atmosphere in the confined space

  • Assure monitors used for atmosphere testing are properly calibrated.
  • Test atmosphere at several locations and heights in the confined space.
  • Test confined space for toxics, flammables and oxygen deficiency.
 

If hot work is to be performed in the confined space, follow proper procedure

  • Obtain hot work permit.
  • Assure gas supply bottles are not taken into confined space.
  • Make sure electrical equipment is connected through a ground fault interrupter.
 

If pneumatic tools are used assure that proper procedures are followed

  • Use only air (not nitrogen) to operate pneumatic tools.
  • Make sure electrical equipment is connected through a ground fault interrupter.
 

Provide proper ventilation and lighting

  • Use positive ventilation on confined space such as blowers, fans or venturi.
  • If flammables are present, use low voltage explosion proof lights.
 

Recognize changes in process conditions

  • Confined space entry that last over several hours or days needs to be secured to assure no authorized entry occurs.
  • Atmosphere is the confined space should be checked before any re-entry to the space.
 

Ensure resources to adequately assess safe work activities

  • Pressure on authorizing personnel to get permits issued can compromise the safety process through the adoption of a “seems OK to be” process. 
  • Assure that there are enough resources to properly inspection the line opening site and positively identify the location of the line opening before permit is issues.
 

Create safe environment

  • Require proper fall protection during the confined space entry.
  • Identify location of the nearest safety shower and eyewash to be used in case of an emergency.
 

Continuous monitoring of the environment; stopping work if hazardous material is detected in the line

  • Confined space entry should be stopped if presence of hazardous material is detected.
  • Hazard evaluation should be completed to determine how the work should proceed or if it should be postponed.
 

Communication is essential between the control room, the Operating personnel and the people conducting the work

  • Communication with the control room at all times is essential. 
  • If an emergency alarm is sounded, all confined space entries must cease immediately. 
  • Area should be re-inspected and confined space entry permit re-issued after emergency is resolved.
 
 
Read More
Hot Work - Strategies & Effective Practices to Manage and Mitigate Hazards

Effective Practices to Manage and Mitigate Hazards

Reduce risk by elimination or substitution; move in-situ work to a less hazardous location

  • Fabrication and modification outside hazardous areas is prefera-ble with minimal hook up activities in situ.
  • Consider deferring hot work to a future turnaround or outage when inventories of flammable materials is the plant at a mini-mum or totally eliminated.
  • Move spark potential equipment such as air compressors outside hazardous areas and use long hoses.

Use alternative methods to welding or gas cutting.

  • Consider bolted connections vs. welding, mechanical cutting equipment vs gas cutting, use of plastic materials and adhesives rather than metals which rely on welding for installation

Create a safe working environment.

  • If welding cannot be avoided in a hazardous area consider building a working enclosure with continuous positive pressure to prevent fugitive gas entry

Defer hot work to a future turnaround or outage.

  • When the risk of hot work is considered unacceptable, considera-tion should be made to defer it until the plant is in a safer condi-tion

Analyze hazards and identify means of control.

  • Survey the worksite and look for potential sources of flammable or explosive substances. Look for open drains and ducting as a source of gas transport. Look for nearby vents and sample points and openings such as filter housings, removable orifice plates, pig launchers / receivers, etc. 

Understand operational status.

  • If the plant is unstable and a potential to trip resulting in depres-surizations exists, caution should be exercised before issuing Hot Work permits.
  • Transfers of flammable materials into storage systems presents the possibility of overfills and spills.

Recognize changes in process conditions.

  • Hot Work permits that extend over many hours need to be reevaluated to ensure the surrounding area and plant conditions have not significantly changed, and that the controls detailed on the permit are still valid.

Ensure resources to adequately assess safe work activities.

  • Time pressure and/or task complexity stresses placed on authoriz-ing personnel to get permits issued can compromise the safety process through the adoption of a “seems OK to proceed” mind-set. These situations are associated with a higher frequency of process breakdowns and the introduction of additional risks.
  • Specify degree of operator presence, consistent with magnitude of identified hazards.

Use hazardous area classification to prohibit specific activities and specify classification of equipment usage.

  • Hazardous zoning of the site enables the specification of the type of equipment allowed within each area.
  • Only electrical equipment meeting the requirements of the haz-ardous area classification should be used in those areas.  This can include, but is not limited to intrinsically safe equipment.  Note - intrinsically safe electrical equipment should be used in these are-as.

Use of sealing / pressurization to prohibit gas entry and access to ignition sources.

  • Electrical switch gear in hazardous areas should be sealed to pre-vent gas entry and / or subject to continuous positive pressure.
  • Control rooms, nearby offices or accommodation should be pres-surised to avoid gas ingress into areas where ignition sources are not necessarily controlled.

Use of ventilation to disperse gas concentrations.

  • Welding and cutting can generate hazardous fumes so ventilation may need to be provided.
  • Preferably, the worksite is well ventilated and not enclosed. 

Use of bonding and grounding to en-sure that static electricity does not accumulate and cause a spark.

  • Understand what processes and equipment are subject to static electricity.
  • Install grounding and bonding cables to applicable equipment.
  • Inspect grounding and bonding cables prior to performing hot work.
  • Replace grounding and bonding equipment if damaged or com-promised.

Continuous monitoring of the environment; stopping work if combustible gas levels are detected.

  • Gas testing should be carried out by certified gas testers.
  • Gas test equipment must be periodically calibrated and tested before use.
  • The authorized gas tester should instruct the work party on the type of continuous gas monitoring (audible alarm preferred) being used and ensure they know how to respond to rising % LEL levels.
  • Work should commence no later than 1 hour after the initial gas test is recorded.
  • If work is suspended for any period, another gas test should be performed before the Hot Work Permit is reissued and work re-commences.

Clear identification of equipment on the plant.

  • Ensure that the equipment to be worked on is correctly identified and labelled so that it will be correctly isolated and purged.  

Isolate, depressurize and purge equipment to be worked on as well as other potential nearby combustible fuel sources.

  • Lock Out / Tag Out should be linked to the permit and a necessary precursor for commencing work.
  • Good practice is to demonstrate the equipment is energy- and gas-free before hot work commences.

Clearing flammable materials away from any areas where potential sparks and/or molten metal could impact.

  • All flammable material within or near the work area should be removed including dust, debris, grease, chemicals, etc.
  • Ensure Safety Data Sheets for any materials which cannot be re-moved are examined for combustion vulnerability.

Use of Hot Work permits to manage activities, specify controls, manage simultaneous operations and communicate to others.

  • Avoid Hot Work simultaneously with hydrocarbon sampling, pig receiving and launching, breaking containment and non-routine process changes. 
  • Ensure no other line break work or hot work being performed close proximity (35 feet / 10 meters).
  • Opening sealed or pressurized electrical equipment such as junc-tion boxes, switches, light fitting, etc., located in hazardous areas should require a Hot Work permit.
  • Motorized vehicles, even those with engine limiters and spark arrestors, should be considered ignition sources and managed as such.

Use of fire watchers; dedicated worker on standby with extinguisher or charged fire hoses as well as communication capability in the event of a fire.

  • A dedicated firewatcher should be part of the work party for any naked flame hot work.
  • Firewatchers should be trained in this role and have the necessary extinguishers and/or charged fire water hoses on hand, as well as communication capabilities.
  • Firewatchers are responsible for ensuring any errant sparks, mol-ten metal or hot debris is properly contained by the fire blankets in use.
  • Firewatchers need to monitor heat being conducted to other, out of sight, areas.
  • The activities of the firewatcher should continue for at least 1 hour following completion of any hot work activities.

Protect areas where sparks and hot debris can impinge and be transported to other plant areas.

  • Fire blankets to capture falling molten metal, hot particles and sparks from impinging on other areas.
  • Wooden and other combustible floors, including scaffolding planks, should be swept, cleaned and wetted down to prevent ignition.
  • Cover ducting and conveyor systems with fire blankets to prevent the distribution of sparks and hot debris.
  • Ducts or conveyor systems near the worksite which could transmit sparks or combustible gases should be shut down.

Identify and seal areas where gas may be transported to the work site.

  • Ensure loops seals on drain systems are charged and openings covered with fire blankets to prevent sparks from entering.
  • Ensure duct systems which could transport escaping gas from oth-er areas are closed for the duration of the work.

Temporary defeat of IR detectors / automatic deluge systems during welding and cutting.

  • If automatic fire detectors are defeated for necessary Hot Work, firewatcher(s) need to monitor all of these areas for any source of fire, not just the hot work.

Ensure that all workers are competent to execute their responsibilities.

  • If automatic fire detectors are defeated for necessary Hot Work, firewatcher(s) need to monitor all of these areas for any source of fire, not just the hot work.

Ensure welding and cutting equipment is in good condition.

  • Provide training to all personnel in Hot Work policies and proce-dures.
  • Ensuring contractors have required craft qualifications.
  • Closely supervise all contractors to ensure they are aware of all hazards and how to respond to emergencies.

Communication is essential between the control room, the Operating personnel and the people conducting the work.

  • Communication with the control room at all times is essential.
  • If an emergency alarm is sounded, all Hot Work must immediately cease and any ignition sources extinguished before responding to the alarm.  All gas checks must be repeated before work can re-commence following an emergency alarm.
Read More
Subscribe to Strategies & Effective Practices to Manage and Mitigate Hazards