Conducting Hazard Reviews: A Practical Guide to Implementing Impactful Process Hazard Analyses

The insights reported here will help guide and encourage engineers in facilitating high-quality and effective hazard analyses in their facilities

Undertaking and completing a well-planned hazard review might just be the best thing you ever do on a single day at work, or in your entire career. It could also very well be an easy task to undertake, or at least to think about and initiate. Initiating and completing a well-thought-out plan for your hazard review can also allow you to create maximum value for your company, colleagues, community and industry — and be a literal lifesaver at the same time (Figure 1).

Creating a hazard review will not necessarily be easy every time, and can involve a number of conflicts and challenges, some completely unexpected. Learning how to use, deploy and conduct effective hazard reviews can also help you become a booster and mentor for others on their journey to excellence in hazard review and analysis. In addition to operational excellence, economic value will come with improved process performance, reduced downtime and associated costs, as well as an improved morale for all team members, who can be proud of their organization.

 

Why do a hazard review?

A question often heard in the past was “Why do I have to do a hazard review? Isn’t this the job of the safety department?” Or perhaps, “I’m a process engineer (or a manager) and I’m way too busy with real work to do this type of activity, give it to someone else who is not as busy!” Or another that is especially painful to hear after an event has just occurred: “I’ve worked here for 10, 20, 30 or 40 years and this has never happened before…”

Do these questions all sound familiar? Hopefully they are not as common as they once were in the chemical processing industries, but unfortunately this attitude still arises from time to time, especially on schedule-driven projects that are over budget and involve specific safety and environmental concerns.

 

What exactly is a hazard review?

A hazard review, and its subsequent analysis, are among the many methods used to assess risk. The process entails describing a system, or a component of the system that involves, or is related to, an activity that could occur within the organization. During the performance of the activity under review or consideration, an event may be encountered that could cause or contribute to the occurrence of an adverse consequence to one, more or all risk receptors, such as safety, the environment, reputation or economic value.

Specifically, a hazard review is the process undertaken to identify, assess and control workplace hazards and the risks to worker health and safety, as well as impacts on other receptors. Most Authorities Having Jurisdiction (AHJ) in North America require employers to establish an occupational health and safety program in their workplace. A hazard review and assessment process is an essential part of an organization’s safety culture and the underlying safety management system. Ensuring that an effective hazard review and assessment system is in place and functioning efficiently goes a long way toward minimizing risks to both employees in the workplace, as well as stakeholders and members of the community. An effective hazard review and assessment program also helps to confirm compliance with safety regulations that are needed to create and maintain a safe work environment for all involved personnel, both company employees and those from partner organizations like suppliers and customers.

 

Basic outline of a hazard review

Hazard or risk analysis involves a structured process used to identify both the extent and likelihood of consequences associated with hazards that may be present. To fully analyze the hazards associated with a scenario at your site and provide an effective analysis to allow risk mitigation, you need to take into account several fundamental concepts, described in the following sections, in the absence of other safeguarding procedures.

Another caveat that the team will need to consider is the fact that most systems never truly eliminate a hazard or a risk unless a redesign is undertaken, the risk is transferred elsewhere, or the activity is never undertaken or permanently stopped. Otherwise, mitigation can only be done by implementing safeguards to minimize or significantly reduce the frequency of occurrence of an adverse event.

For example, consider the manufacture of paint products from flammable hydrocarbons that can potentially explode or cause a fire. In this case, nothing can be done within the existing process to fully eliminate a fire or explosion hazard risk, unless you were to change the manufacture over to a completely different paint formulation. This would eliminate the risk of explosion, replacing it with other, less severe risks that would then have to be reviewed and mitigated by other means and methods.

Step 1 — Recognition of a scenario, or “knowing that you don’t know.” Where do you start? You may have been lucky, and have never had an accident before at your site — or so you’ve been told. Or, you’re a new employee and you’ve been asked to undertake a hazard review, for example, related to the use of natural gas within a process to fire a burner using a compressed-gas cylinder.

Start by recognizing that you “know that you don’t know” and work toward knowing all you can. This includes gaining knowledge of the work process for completing a hazard review and analysis, and the specific task at hand, which in this case, would be the safe and effective use of compressed-gas cylinders inside a building to fire a burner system. To best accomplish this task, the following tasks are recommended:

• Do a “walk-around” using the appropriate personal protective equipment (PPE) assigned to you. Observe the area where the gas cylinder will be used and complete a sketch of the area to familiarize yourself with the layout and any facility siting concerns
• Ask fellow employees or other people in the area about what issues could arise by installing or using a natural-gas fired burner
• Inquire about any other related past incidents at the site, either within the company itself or the industry in general
• Research potential related issues in the public domain
• Assemble a reference package of all key process safety information (PSI), including (but not limited to) the following:
• Safety datasheets (SDS) for the natural gas (methane) that will be contained in the cylinder
• Burner and cylinder details from the original equipment manufacturer (OEM)
• Information on gas detection systems, either installed or portable, being used on site
• Handling procedures for compressed-gas cylinders
• Building and workspace access and egress routes, for both normal routing and under emergency conditions
• Confirmation of who normally works in the area and for what period of time to establish whether or not the area is considered to be an “occupied space” or not. One key factor that clearly establishes 100% occupancy is if there is a meeting room in the immediate area that anyone can book at any time of the day, or a training room, lunchroom or an office with a person’s name assigned to it, who works day or night shifts in a role that is covered over the entire year

Step 2 — What could go wrong in the absence of safeguards? Work with a colleague, especially someone who will be in the workspace and possibly will be responsible for receiving, using and handling the natural-gas cylinder, as well as operating the burner system, to generate a list of possible scenarios that should be considered in a hazard review and analysis. Refer to the SDS for methane, the burner and cylinder operating manuals and any relevant OEM brochures to get a comprehensive list of scenarios and safeguarding to be used or present (Figure 2). Factors to consider include the following:

• Receipt and movement of gas cylinders
• Primary valve break on the high-pressure natural-gas cylinder
• Loss of primary containment (LOPC) of the natural gas into the facility, considering the below cases:
• No ignition case, no gas odorant present, people present
• No ignition case, gas odorant present, people present
• Delayed ignition case, people may be present
• Immediate ignition gas, people may be present

Step 3 — How likely is it to occur in the absence of safeguarding? If in doubt, “go big or go home” and assume an occurrence of an event taking place anywhere from once per year to about once every 10 years. For the compressed-gas cylinder example, we will assume a leak from a faulty gas-cylinder valve connection with people present and absolutely no safeguarding in place. Note, the proviso of “in the absence of administrative and engineering safeguards” is a requirement for a number of best practices, such as those required by the U.S. Dept. of Labor’s standard, OSHA CFR 29 1910.119 — Process Safety Management of Highly Hazardous Chemicals, and is used so that safeguards are not credited more than once, and that the focus is on the worst case, not the most likely, less harmful case. This legislation contains requirements for preventing or minimizing the consequences of catastrophic releases of toxic, reactive, flammable or explosive chemicals. These releases may result in toxic, fire or explosion hazards.

Should an LOPC occur with people present, and there is no gas detector available, no odorant in use and no ventilation, then as according to the SDS, without ignition, the released methane could displace the air in the room and the oxygen concentration could be reduced below 19.5 vol. %, compared to a normal concentration of about 21 vol. %, which could then result in the asphyxiation of any and all people present during the time of the release.

Step 4 — What are the consequences that could occur for all risk receptors? These consequences may include adverse impact on people (loss of life, injury or illness), the environment (harm to air, water and soil, both on and off the physical site) and finances (damage to property or assets, loss of revenue or negative reputational impact). Some potential risk outcomes are listed below for the compressed-gas cylinder hazard scenario:

• Asphyxiation — Fatalities and equipment damage, as well as production outages and potential environmental release
• Flash fire — Fatalities or burns and equipment damage
• Explosion — Fatalities and equipment damage
• Jet fire — Fatalities or burns and equipment damage

Step 5 — What is the level of risk in the absence of safeguards? Note, to confirm all of the below considerations for the risk receptors, it is necessary to fully develop an approved corporate risk assessment matrix (RAM).

• Safety — High, unacceptable without safeguards
• Environment — Low, unacceptable without Safeguards, regardless of the risk
• Economics — Medium, unacceptable without safeguards, regardless of the risk
• Reputational risk — Cannot be developed without corporate guidance via an approved RAM.

Step 6 — What can you do to eliminate or mitigate the harm and reduce the level of risk? Below are some recommended practices to address the hazard and risk associated with the compressed-gas-cylinder scenario.

• Develop operating and maintenance procedures, complete with training
• Use gas only with odorant
• Move any burn to an inherently safe location, like outside of the building
• Control access to the area
• Employ gas detection and appropriate heating, ventilation and air conditioning (HVAC) systems
• Explore the potential use of non-fired equipment
• Specify flame-resistant PPE
• Check for leaks and pressure-test all equipment prior to use
• Explore the use of a burner management system (BMS)

Step 7 — How much will it cost to achieve significant and realistic safeguarding? This cost should look at not only financial resources, but also employee time and effort, to determine if the cost will be proportional or disproportional to the reduced level of risk. For example, if it will cost $1 million to mitigate a risk that is only costing $10,000, is this recommendation a valid one for the organization to undertake? Or, alternatively, if the mitigation requires a number of team meetings and expenses to design, acquire, install and maintain, and the likelihood and the consequences do not change, is the of value to your organization to adopt even more work of low, or questionable value? Below are some specific questions to consider.

• How much will it cost to reduce your risk from High/Unacceptable to Medium/Acceptable with safeguards, or even to Low Risk?
• Will the costs to achieve an acceptable level of risk be within budget? If so, and management approves and supports your review, then you can begin establishing an “As Low as Reasonably Practicable” (ALARP) assessment on your hazard reviews and analysis procedures. ■

 

References

1. Center for Chemical Process Safety (CCPS) “Guidelines for Hazard Evaluation Procedures,” American Institute of Chemical Engineers (AIChE), 3^rd Ed., April 2008.

2. Pitblado, R. and Turney, R., “Risk Assessment in the Process Industries,” IChemE, February 1996.

3. Crowl, D. A. and Louvar, J. F., “Chemical Process Safety: Fundamentals with Applications,” Prentice Hall, 3 ^rd Ed., January 2011.

4. U.K. Health & Safety Executive, Managing risks and risk assessment at work, https://www.hse.gov.uk/simple-health-safety/risk/print.htm.

5. R. E. Knowlton, “An Introduction to Hazard and Operability Studies – The Guide Word Approach,” Chemetics International Co., 1992.

6. U.S. Dept. of Labor, OSHA 29 CFR 1910.119, Process Safety Management of Highly Hazardous Chemicals, Sept. 2014.

 

Author

Bill Timbers, P.E., P.Eng. is an engineering consultant specializing in risk management, process safety management, operational excellence and business consulting (Email: [email protected]). He holds degrees in chemical engineering and applied chemistry, and has completed advanced graduate studies related to risk and occupational health and safety at the University of Alberta, the University of Houston and the London School of Economics. Timbers is a registered professional engineer in both Texas and Alberta, and has worked for many years in the chemical industry in project management and production and process engineering roles.