iFluids Engineering and Consultancy WLL conducted SIMOPS study for Khuff Gas Pipeline From Dukhan To Mesaieed. For the last 30 years, the existing 30-inch ONSAG pipeline buried between Stations in Mesaieed is being used to transport the sour gas. Due to the continuous service, the condition of the Khuff Gas pipeline has deteriorated. Hence, to avoid the leakage of the high H2S content gas, regular maintenance work is carried out to evade any hazardous condition. However, Qatar Petroleum (QP) has conducted a detailed study/workshops in consultation with all department to find a permanent solution to this condition
QP has proposed an idea to divert the ONSAG through existing 36-inch Khuff gas pipeline in Dukhan to Mesaieed in Doha. The supply of the khuff gas to the customers will be carried out through the existing 36-inch SFG network. Hence, to achieve this objective QP wants to carry out various modification at various operating and distribution stations.
These modifications are intended to be carried in two phase i,e Phase-1 and Phase-2. The Simultaneous Operations (SIMOPS) workshop was focused on FSDGS, Umm bab metering station.
The objective of SIMOPS study
SIMOPS is defined as the HSE Assessment for works inside an existing operating facility or works for new facilities within the vicinity of an existing operating facility whereby two or more operations are being performed concurrently.
The term “Works”, within context of this definition denotes “operational”, “maintenance”, “troubled-shooting”, “logistical” and “construction” activities.
In a more elaborate format of definition, the objective of SIMOPS is to identify all potential hazards of any one operation and their consequential impacts on the other operation or operations when two or more operations are to be carried out at the same time.
SIMOPS Assessments for the following main reasons:
- Automated Systems are usually engineered and designed with provision of the adequate Safety Controls that have been concluded and recommended by all the HSE requirements defined for the project; e.g. HAZOP, FMEA, SIL, HIPPS, etc.;
- Hence, impacts from the automated systems on personnel and/or assets (property) should fall within the As-Low-As-Practicable (ALARP) Region and are therefore accepted.
Not withstanding provision of an ALARP atmosphere within a facility by virtue of its engineering design, ‘automated’ systems occasionally require “manned operations” to be carried out; viz. during Start-ups, Abnormal Operations, Shutdowns as well as during normal operations. When these manned operations are carried out concurrently, SIMOPS Assessments are then also needed.
Overall, SIMOPS is expected to cater to one or a combination of the following potential work scenarios:
- Concurrent “manned” operations/works within an existing facility during its normal operation;
- Construction works of new facilities in an existing operating facility;
- Modification works within an existing operating facility; and/or
- Construction works of new facilities in the vicinity of an existing operating facility.
The overall objective of the SIMOPS assessments, as an HSE Tool (Model), is to identify the “Hazards” resulting from one operation (activity) that could impact onto another concurrent operation and vice-versa so as to eventually conclude if any of these would pose “risks”.
This is achieved by conducting a Hazard Identification (HAZID) exercise based on a comprehensive list of activities for the two or more concurrent operations. Once the SIMOPS hazards have been identified their risks and possible impacts must be assessed and reviewed so as to take the necessary measures to waive or mitigate and manage the situation.
All ‘Hazards’ identified from the HAZID assessment are to be eventually qualified (or quantified) by use of the project specific Risk Matrix, to conclude if they pose “Risks” and whether these risks represent “unacceptable” risks; i.e. not falling within the As Low As Reasonably Practicable (ALARP) region. Under the circumstance, a “Risk Management” exercise to be carried out.
In order to determine if the “hazard” from one operation that impacts another concurrent operation is a source of an “Unacceptable Risk”, the Frequency (F) of the hazard’s occurrence and the Severity (S) of its impact are to be concluded from the project specific Hazard Matrix.
When the hazard is concluded to be a source of “Risk”; i.e. falling outside the ALARP and within the “Unacceptable Region” of the Matrix, Risk Management for the purpose of a SIMOPS exercise could be achieved by either one of the following two courses of action:
- Hazardous Activities impacting each other could be avoided if either one of the concurrent activities is “staggered”; i.e. carried out at different timings. This approach implies rescheduling of the SIMOPS plan; or
- If ‘staggering’ of SIMOPS is unachievable or uneconomical, provide the necessary Safety Controls; i.e. ‘Layers-of-Protection’ and/or ‘Barriers’ that will ensure having the risks to fall within their ALARP region.
To re-schedule an activity by postponing it to a later timing may impact the overall plan to complete the works and may increase the project’s costs as well. This is materialized by any or all of the following:
- The ‘team’ in charge to carry out the “postponed” activity (operation) shall stand idle waiting for their turn to proceed with their assignment; thus, non-productive man-hours are being consumed;
- Similarly, rented equipment if any is needed for the job, shall be paid for without actual usage during the ‘idle’ periods;
- Delayed completion of the activities may affect the ‘facilities revenue’ especially in case of delays in “productivity’ and its corresponding ‘sales’
- Project delays may be subject to contractual penalty clauses (liquidated damages, performance bonds, etc.);
- Other disadvantages depending on the nature of works being carried out
SIMOPS refers to the concurrent execution of multiple tasks by two or more functional groups in a shared location. SIMOPS is a term used in the Oil & Gas and Petrochemical industries to refer to the situation where construction, commissioning, start-up, and production operations are being executed concurrently. In this context, apart from the inherent dangers associated with each individual task, there is a possibility of further perils arising from the concurrent performance of activities within the same vicinity.
To effectively mitigate the risks associated with SIMOPS, it is imperative to establish a specialised risk assessment process that involves all relevant stakeholders, including the asset/plant owner, project management consultant, main contractor, subcontractors, and vendors. This process should aim to identify potential hazards and implement measures to eliminate, minimise, or manage the identified risks.
The objective of the SIMOPS risk assessment procedure was to meticulously examine and assess the construction, commissioning, start-up, and operational activities that are planned to be carried out simultaneously, with the ultimate goal of pinpointing any supplementary hazards that may arise due to the SIMOPS.
- Evaluating the pertinent degree of hazard;
- Confirming the sufficiency of the intended mitigation strategy;
- Identifying additional risk reduction measures;
- Provide input to Permit to Work process for embedding additional controls.
All the project’s parties as asset/plant owner, project management consultant, main contractor, subcontractors and vendors were actively involved in the entire SIMOPS risk assessment process.
The SIMOPS risk assessment study workshop is the initiating event of SIMOPS risk assessment process, the key forum to share necessary information and to properly coordinate the involved parties. Participation of a multidisciplinary study group from all project’s actors is a mandatory requirement. The workshop was conducted by a SIMOPS facilitator who was tasked with moderating and encouraging discussion among the participants.
The SIMOPS workshop involved the implementation of a series of procedures under the supervision of the SIMOPS facilitator.
- To identify the SIMOPS scenarios, with a particular focus on identifying the concurrent activities that are to be executed during the introduction of hazardous materials or energy sources.
- Identification of the related hazards;
- Evaluation of the risk of simultaneous execution of the activities;
- The task at hand involves identifying the control measures and/or operating procedures that have already been planned, followed by assigning responsibility for their implementation.
- Evaluation of the residual risk with risk control measures already in place;
- Identification of additional risk control measures, if required;
- Assignment of responsible person for the implementation of identified countermeasure
Furthermore, the workshop provided propaedeutic documentation in the following manner. The following items have been provided for the project:
- An updated schedule outlining the construction, pre-commissioning, commissioning, and start-up activities;
- Process flow diagrams (PFD) and piping & instrumentation diagrams (PID);
- Plant layouts and equipment layouts;
- Material safety datasheet (MSD) for the substances being handled;
- Hazardous areas classification drawings;
- Details regarding manning levels and worker distribution in areas involving SIMOPS.
- Layout showing Permit to Work areas;
- Layouts showing location of temporary construction devices as crane, diesel generator, welding machines, scaffolding, etc.; and
- Quantitative Risk Assessment (QRA) and consequence analysis developed during detailed design (if available).
The initial phase of the SIMOPS workshop entailed the discernment of the SIMOPS scenario, its classification, and the timetable of concomitant undertakings. According to starting date of energy source (hydrocarbon, pressure, power) introduction in a certain unit, specialists from construction and commissioning pointed out the activities planned to be executed in the same area involved by the introduction of energy source.
A thorough hazard identification process was conducted for each SIMOPS scenario. Discipline specialists provided detailed information regarding the planned activities concurrent with introduction of connection with feed power source, as starting date, special tools to be used, manpower involved, affected area, duration, etc.
The utilization of a structured guidewords approach facilitated the examination and identification of potential hazards linked to each SIMOPS scenario. Special emphasis was placed on the supplementary risks arising from the concurrent performance of the two tasks.
In accordance with HSE (Health Safety Environment) management system of the QG, the risk associated to each identified SIMOPS scenario was evaluated through semi-quantitative risk assessment method as per QG risk matrix.
Two different risk levels will be assessed. The first one is known as “Initial Risk” was set without considering any risk reduction measures, and the second one known as “Residual Risk”, taking credits from control measures and operating procedures existing or planned to be carried out during the execution of the concerted activity. To each identified countermeasure the subject responsible for its implementation should be defined and agreed by all team member.
The scribe recorded the significant points arising from the discussion of the SIMOPS risk assessment review team in real time so that all team members of the SIMOPS risk assessment workshop can read the worksheet and comment upon or change the recorded comments.
After completion of the SIMOPS risk assessment review session, a series of Action Sheets need to be generated with assigned responsibility to each action to ensure that it is followed up and closed out in an appropriate manner.
