Before an employee enters the space, the internal atmosphere shall be tested, with a calibrated direct-reading instrument, for oxygen content, for flammable gases and vapors, and for potential toxic air contaminants, in that order. We test for oxygen before testing for flammability (LEL) for two (2) critical reasons: Here is the breakdown of why this…...
The rule—”Add Acid to Water” (AA)—is one of the most important safety practices in a chemistry lab. It all comes down to how much energy is released when they mix and how the liquid behaves as a result. Let’s explore the science behind this safety rule together. I’ll ask guiding questions along the way…. Membership...
The frequency for testing or replacing hydrostatic relief valves (HRVs) depends largely on the service environment, the fluid being handled, and the specific regulatory standards like OSHA, NFPA, CGA, or ASME governing your process. Because these valves are designed to protect against thermal expansion in liquid-filled lines—often in “blocked-in” sections—their reliability is critical to preventing…...
If we are making a final “tie-in” weld between two segments of pipe that have already been independently pressure tested, that specific weld can be exempt from a final system pressure test if:… Membership Required You must be a member to access this content.View Membership LevelsAlready a member? Log in here...
On April 9, 1998, two volunteer firefighters died in Albert City, Iowa, and six responders were injured when a burning LP-Gas tank exploded in a boiling liquid expanded vapor explosion (BLEVE). CLICK HERE for this NFPA Article on the incident…. Membership Required You must be a member to access this content.View Membership LevelsAlready a member?...
Technical documentation prepared for: Transport Canada Canadian Association of Fire Chiefs Propane Gas Association of Canada Inc. This document is intended to go with the video of the same title, and will provide the viewer with additional technical information to support the content of the video. It is recommended that the video be viewed first,…...
The Incident: In September 2000, a steel lecture bottle located within a hood in a UNR laboratory ruptured with explosive force. The explosion occurred at night, and no one was present in the laboratory at the time. However, there was significant damage to the lab hood. The gas cylinder contained methyl nitrite (CH3ONO), which had…...
In the realm of process safety, a Functional Test of the Safety Instrumented System (SIS) is a periodic procedure performed to ensure that an SIS will operate as designed when a real-world demand occurs. While a system might look operational on a control panel, internal “hidden” failures could prevent it from actually shutting down a…...
I encountered something new this week; well, new to me, as I have never seen an RT Rejection rate of 26%. So I knew that was crazy high, as the normal rate is around 2-3%. So I had to go back to my ASME B31 Course and research an acceptable rate:… Membership Required You must...
Managing static electricity during the transfer of flammable liquids is based on the fluid’s conductivity, measured in picosiemens per meter (pS/m). High-conductivity liquids dissipate charge quickly, while low-conductivity liquids (static accumulators) hold onto the charge, creating a spark hazard. The following table summarizes the maximum flow velocities recommended by NFPA 77 and API 2003 to…...
