HAZOP Explained: Nodes, Guidewords and Deviations
How a hazard and operability study works, what makes a good node, and how to keep a HAZOP productive.
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Process safety resource library
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Articles by Aetso Technical
LOPA Fundamentals: Scenarios, IPLs and Risk Targets
A plain-language walkthrough of Layer of Protection Analysis and the rules that make an IPL credible.
Does OSHA PSM Apply to Your Facility?
The applicability tests in 29 CFR 1910.119, common exemptions and how PSM relates to EPA's RMP rule.
Management of Change That Actually Catches Changes
What counts as a change, replacement-in-kind pitfalls and how to design an MOC process people will use.
Pre-Startup Safety Review: A Practical Guide
When a PSSR is required, what it must confirm, and how to avoid a check-the-box review before startup.
Process Safety Glossary
Plain-language definitions of the acronyms and terms used across process safety: from ALARP to TQ.
OSHA 29 CFR 1910.119 — Process Safety Management standard (opens external site in a new tab)
The regulatory text of OSHA PSM, including Appendix A threshold quantities.
OSHA Process Safety Management topic page (opens external site in a new tab)
OSHA guidance, enforcement information and resources on PSM.
EPA Risk Management Program (RMP) (opens external site in a new tab)
EPA overview of RMP requirements, rulemaking status and guidance.
40 CFR Part 68 (eCFR) (opens external site in a new tab)
Current text of the Chemical Accident Prevention Provisions.
OSHA combustible dust (opens external site in a new tab)
OSHA information on combustible dust hazards and enforcement.
Center for Chemical Process Safety (CCPS) (opens external site in a new tab)
AIChE's center for process safety guidelines, training and research.
Process Safety Beacon (opens external site in a new tab)
CCPS's monthly one-page lessons for operators, in many languages.
U.S. Chemical Safety and Hazard Investigation Board (opens external site in a new tab)
Independent investigation reports and safety videos on chemical incidents.
CAMEO Chemicals (opens external site in a new tab)
NOAA database of chemical hazard data, including a reactivity prediction tool.
International Society of Automation (ISA) (opens external site in a new tab)
Publisher of ANSI/ISA-61511 and ISA-18.2.
National Fire Protection Association (NFPA) (opens external site in a new tab)
Publisher of NFPA 660 and other fire and explosion codes.
American Petroleum Institute standards (opens external site in a new tab)
API standards including API 520, 521, 752 and 754.
About external resources
External links are provided for convenience and point to the original publishers. Aetso Technical is not affiliated with or endorsed by these organizations. Standards are copyrighted by their publishers and must be obtained from them.
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