Dates: Jan 1, 2024
Imagine buying an unlabeled chemical and adding it to your product without researching, planning, or knowing the ingredients and understanding their potential effects. Would you risk your safety and budget on a product based on false assumptions? Not likely. Yet the chemical industry is filled with incidents where the unknown and untested are often put into practice. Then the unthinkable happens. A toxic chemical is released, someone is fatally injured, and a facility is destroyed.
Risk-screening methods are essential for mitigating costs and protecting your most important resources ― your people. A quality facility siting study will consider the risks of fire, toxicity, and explosion to the building occupants. These studies can help companies decide if, for example, it would be much more cost-effective to reduce the likelihood and impact of large release scenarios by adding detection and isolation systems, rather than the relocation or blast-proofing of control rooms.
Learn important lessons from three historical incidents on what happens when companies neglect to identify, evaluate, communicate, and mitigate the risks with a facility siting study.
On February 19, 1999, a batch of Hydroxylamine (NH2OH) compound exploded at a small chemical factory, killing five workers and injuring six more. The facility was destroyed and several buildings in the industrial park were also damaged during the incident, including a daycare center. Property damage was estimated between $3.5 and $4 million. The image below shows the extensive damage.
Concept Sciences Inc. building damage and charge tank crater
The incident report from the U.S. Chemical Safety and Hazard Investigation Board cited the failure to produce engineering drawings and detailed operating procedures as one cause of the explosion. A lack of follow-up by Concept Sciences Inc. to implement safeguards after conducting a Process Hazard Analysis (PHA) study was another key factor. Essential safeguards such as remote control operation, blowout walls, and shielding for protecting employees were missing. Moreover, the firm was notified by its principal client, Ashland Chemical Company, that the site they chose for its facility was not a good location for the chemical process.
On March 23, 2005, a series of explosions and fires occurred during the restarting of a hydrocarbon isomerization unit at the BP Texas City refinery. Fifteen workers were killed and 180 others were injured during the incident. The blasts destroyed thirteen trailers and damaged twenty-seven others within 1,000 feet of the ISOM unit. The incident cost the organization an estimated $3 billion in damages and legal settlements.
At that time, there were numerous facility siting issues in the refinery, including:
By not collecting appropriate information, assessing vital signs, and communicating lessons and knowledge of hazards, a very serious fatal explosion occurred.
Refinery layout of the area surrounding the ISOM unit
Blast overpressure map of trailer area where structural indicators show a blast overpressure of 2.8 psi
Damaged trailers after the 2005 incident
On November 22, 2006, a confined vapor cloud explosion in Danvers, MA destroyed the CAI/Arnel ink and paint manufacturing facility, hospitalized at least 10 residents, and damaged beyond repair dozens of nearby homes and businesses. The company was issued thirteen serious citations and fines of over $1.3 million for reimbursement of hazardous waste cleanup.
OSHA's PSM regulations require that facility siting be addressed in Process Hazard Analysis (PHA). A quality study would have identified, analyzed, and documented safety measures and safeguards for the handling of flammable solvents. CSB Lead Investigator John Vorderbrueggen, P.E., noted, “Such a review could have identified the need for more sophisticated process control equipment, operator checklists, and continuous building ventilation.” Failure to conduct a PHA study and lack of written procedures or checklists were among the causes of the incident according to the U.S. Chemical Safety and Hazard Investigation Board report.
Aerial view showing damage data points and estimated explosion overpressures out to about 600 feet from the facility
Aerial view of the facility explosion damage
Historical incidents like these led to a safety improvement in the American Petroleum Institute (API)'s recommended practices, “to exclude wood-frame trailers from within 330 feet of hazardous processes.” API RP 753 (Management of Hazards Associated with Location of Process Plant Portable Buildings), developed and issued in June 2007, applied a three-zone method for locating portable buildings. Each zone is based on the size of the congested process area and the distance from the edge of this congested process area to the portable building.
Portable buildings location guidance from API RP 753
For the three zones, light wood trailers intended for occupancy should be located in Zone 1. Other portable buildings require a detailed analysis before being placed in Zone 1. All portable buildings within Zone 2 also require detailed analysis. Finally, any portable buildings may be located in Zone 3 without detailed analysis.
According to API RP 752, a detailed analysis may take the form of a consequence analysis approach, a quantitative risk analysis approach, or a spacing tables approach. By taking a risk-based approach, the facility siting can provide your organization with the most comprehensive awareness of onsite risks and the most cost-effective resolution. Problem areas can be easily identified thanks to the ability to segment, filter, sort, and compare risk results. Additionally, it can be utilized to include a cost-benefit analysis.
Large oil and gas and chemical processing facilities operate facilities where hazardous materials are processed and/or stored. These facilities include buildings with varying levels of occupancy that may be at risk from accidental releases that can cause fire and explosion damage and/or toxic chemical exposure.
The design of older facilities may have not initially considered/addressed facility siting risk and may have placed more emphasis on operability and efficiency of operations. It is not typical, for example, for an oil and gas processing facility that was built in the 1950’s to have blast resistant control rooms or office buildings, even though these buildings may be very close to operating units processing large volume of hazardous chemicals.
Building risk evaluation methodologies that are too conservative can lead to excessive mitigation costs without achieving the intended risk reduction. Building risk evaluation methodologies that are inadequate can leave companies exposed to high levels of risk for its portfolio of buildings.
Read the white paper Properly Evaluate Building Risk and Facility Siting by Georges Melhem, Ph.D., FAIChE, for in-depth guidance on facility siting.
The professionals at ioMosaic have a proven track record of performing quality facility siting studies on a wide range of facilities, such as refineries, chemical plants, pharmaceutical plants, LNG facilities, and more. We deliver practical, locally compliant solutions to our clients' safety and risk concerns. Call us today at 1.844.ioMosaic or send us a note with your questions on facility siting. We'd love to hear from you.