NFPA 496 (Standard for Purged and Pressurized Enclosures for Electrical Equipment) is one of the most powerful engineering tools available for hazardous locations, but it is also one of the most abused standards for HAZLOCs. Like the Combustible Gas Detection System (CGDS) provisions in NFPA 70, NFPA 496 allows a facility to install ordinary, non-classified…...
In NFPA 70 (National Electrical Code / NEC), the use of a Combustible Gas Detection System (CGDS) is a highly specialized engineering provision. It essentially acts as a “get out of jail free” card—or more accurately, a reclassification tool—for specific industrial locations. When you install a qualified CGDS, the NEC allows you to lower the…...
Auto-Refrigeration & Flashing and Cold Ambient Exposures We see around a half dozen pressure vessels in a “service” they were not initially designed for. There are literally hundreds of excuses as to why we find these issues, but they are simply excuses. It was not uncommon for us to find a PV in an NH3…...
The concept of the weak seam welded roof—officially referred to in modern engineering standards as a frangible roof joint—has been a foundational safety mechanism for atmospheric storage tanks for over 90 years. NOTE: In 2015, NFPA 30 Section 22.7 was amended to eliminate the use of a weak roof-to-shell seam as an allowed means of…...
As most of you know, PRCS Entry is one of the specific SWPs called out in the PSM and RMP standards. But many programs fail to meet 1910.146(f)(4), and a recent CSB accident report tied the requirement for canceling a permit to a catastrophic explosion event. 1910.119(f)(4) The employer shall develop and implement safe work…...
NTSB’s historical investigations into major gas and hazardous liquid pipeline ruptures continue to shape current rulemaking tracking. PHMSA has been actively reviewing the established Potential Impact Radius (PIR) calculation methodologies used in integrity management programs. The review aims to determine whether current mathematical models accurately account for human response data, rapid-ignition variables, and modern accident…...
In today’s workplaces, it’s hard to find a large business that does not require Hi-Vis Vest/Workwear. What is not hard to find is a business with HAZLOCs where workers are required to wear FRC but are wearing nylon Hi-Vis vests OVER their FRC. I am all for making workers more visible to powered industrial trucks…...
I took these pics for those who may have never seen a FAILED leak test using a “bubble solution”. We have discussed the “sensitivity testing” using the bubble test method many times, as it’s the most common method. I have been using the brand SNOOP my entire career and highly recommend it. (an unpaid endorsement)…...
We have another tragic example of how dangerous hot work is on used (even new) containers when proper precautions are not taken. This event seriously injured the three (3) workers in Ankara, Turkey, in February 2024. Members can download the video from the video library…. Membership Required You must be a member to access this...
Many may be familiar with “flange jumpers,” or some may call them “bonding jumpers,” that are used to ensure a continuity to ground across a flange with gaskets that act as “insulators”, such as PTFE gaskets. During a recent walkdown of a flammable liquids process, I came across this “jumper”. Design called for “jumpers” on…...
Yes, I am still on this horse! As I discussed last month, there are a number of chemicals that specifically REQUIRE HRVs on liquid piping. Those are chemicals like NH3, Cl2, and LPG, to name the top three (3). But I have recently read a root cause analysis in which a flammable-liquid piping flange leaked,…...
I have written over a dozen posts explaining the code requirements for annual inspection/testing of our chemical hoses. But in the world of PSM/RMP, there is another hose that requires annual inspection and testing… The primary standard requiring fire hose to be service-tested annually is NFPA 1962, Standard for the Care, Use, Inspection, Service Testing,…...
