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MMI Engineering to Present on Process Safety at IChemE’s Hazards 28

Richard Emery, Euan Stoddart, and Ian Herbert (Manchester) will present at Hazards 28 at the Mary Kay O’ Connor Process Safety Center in Edinburgh, Scotland on 15-17 May 2018.

Richard has significant experience in Fire Risk Assessment (FRA), Safety Integrity Level (SIL), As Low As Reasonably Practicable (ALARP), Hazard and Operability (HAZOP), and Passive Fire Protection requirements. He has also played a significant role in the development of MMI Engineering’s proprietary QRA software. Richard has process design and simulation experience of various ethylene, LNG/LPG and refinery plants through concept: basic, front-end engineering design (FEED), and detailed engineering phases.

Euan is a Senior Engineer based in England with more than nine years of experience in structural analysis and response. He has experience within the security, nuclear, oil and gas industries including analysis and assessment of structures and subsystems such as stations, offshore platforms, pipework systems, nuclear facilities, and dock systems.

Ian is a Principal Engineer based in England with more than 30 years of professional experience in process safety including the identification of major accident hazards through risk assessment; and determining and defining measures to prevent, control, mitigate, and respond to hazards.

Hazards conferences share expert knowledge, latest developments and lessons learned in process safety, promoting a continuous focus on safer operations. Covering major aspects of process safety and aimed at anyone who is active in process safety and risk management, they provide essential insight into how to manage and reduce risk effectively and offer excellent networking opportunities. First staged in 1960, Hazards is held annually in the UK and is widely recognised as Europe’s leading process safety event.

The Institution of Chemical Engineers (IChemE) is a global professional membership organisation for chemical engineers, biochemical engineers, process engineers, and other professionals involved in the chemical, process and bioprocess industries. With a membership exceeding 40,000 members in around 100 countries, IChemE aims to be the organisation of choice for chemical engineers.

MMI Engineering Participation

Title: Maximum Allowable Valve Passing Rate Review and Determination
Presenter: Richard Emery
Time: 12:05-12-:35 on Wednesday May 16, 2018
In the event of a process leak, Emergency Shut Down Valves (ESDVs) are required to limit the potential for escalation by restricting the amount of material available to be released. A newly installed valve will provide good isolation and not allow any material to “;pass’ when in the closed position. For valves in service however, corrosion, erosion and other factors will serve to degrade the performance of the valve and lead to the valve passing when in the closed position.
Valve passing studies are required to determine what the maximum allowable passing rate should be for valves in service. For offshore riser valves, requirements are laid down by the HSE [1], however these guidance notes may be applied to other inboard ESDVs and ESD valves onshore also.

MMI has carried out a review of valve passing studies conducted by MMI and other consultancies for a variety of operators and has failed to identify a single comprehensive methodology to cover all cases. In response to this, MMI have developed a valve passing methodology which is intended to clarify and simplify the overall valve passing study process.

This paper discusses the relative merits of previous methodologies, then provides a detailed description of MMI’s consolidated approach to study this problem for flammable releases. An example assessment for a typical offshore installation is then provided using MMI’s proprietary valve passing assessment software.

Title: Gas Explosion Protection for Aerosol Filling Rooms – Full Scale Testing and Analytical Validation
Presenter: Euan Stoddart
Time: 13:30-14:00 on Wednesday May 16, 2018
Almost all domestic aerosols are propelled by a liquefied compressed gas.  Since CFCs were banned in the 1970’s these are mainly flammable LPG propellants (propane/ butane blends).  Aerosols are filled with propellants in dedicated unmanned buildings external to the main factory on a site. Cans are filled at a significant rate of up to 500 cans per minute (each with up to 200ml of LPG).  Therefore, a significant explosion hazard exists should a leak and subsequent ignition occur.  There are a number of layers of protection to reduce the consequence of such an event such as hazardous area classification, gas detection, forced ventilation, unmanned operation and automatic shutdown.  Despite this, there is the potential for these barriers to fail or for the release to be of such a size that a significant explosion could occur.  In these instances, a demand is then placed on the venting provided on the building and the strength of the structure to withstand the blast.

Title: Factors in the Selection Philosophies and Criteria to Improve F&G Detection and Use of PFP
Presenter: Ian Herbert
Time: 16:50–17:20 on Wednesday May 16, 2018
Following a release of hazardous materials, fire and gas (F&G) detection and Passive Fire Protection (PFP) are significant control and mitigation measures in the prevention of escalation. However, the design specifications for F&G detection and PFP such as: the requirement for, extent of coverage of, and functionality, often default to the following of prescriptive guides and qualitative “;rule of thumb’ philosophies based on the initiating release and fire hazard. This fails to fully take into consideration the potential type and scale of the ultimate escalation consequences for which the F&G and PFP measures are to protect against.
In the worst case this can lead to under specification and lack of appropriate cover. But, over specification of F&G and PFP can also occur with cost implications, potential degradation of response and increased maintenance requirements. This could also lead to increased risk to the associated maintenance teams due to increased exposure to facility hazards.
This paper details the roles and issues associated with F&G detection and PFP application. It also details how these measures should be determined using performance-based selection and design assessments. This can be though qualitive assessments through semi-quantified (risk matrix) to quantified modelling using probabilistic screening criteria.

More Information

Learn more about the conference:
Learn more about the schedule: Hazards 28 Agenda.
For consultation regarding hazardous materials or fire and gas, contact Ian Herbert at
Learn more about Richard at:
Learn more about Euan at:
Learn more about Ian at: