Over the years I have facilitated and participated in hundreds of PHAs from toxics to flammables and even some explosives (although not my thing!). And in doing so, one thing that drives me crazy is the lack of structure in how process deviations are identified and studied/analyzed. I love the HAZOP methodology and hate the What-if methodology for this very reason. But I also go crazy when I am a guest in a client’s PHA and someone else is facilitating the study and never challenges any of the “safe guards” – even when the safe guard is not documented in the PSI, SOPs or Training records. But if you want to push me over the edge, go through a scenario and assume the “alarm” will be 100% successful in avoiding/correcting the deviation; even when the facility does not have the alarm set point defined in the PSI or the specific steps included in the SOP for dealing with this “alarm”! Now I am not disparaging any of the PHA methodologies, but I am hoping to open some eyes in how we should be approaching our PHA(s), regardless of the methodology used. In this article I will sort of touch on the new PHA methodology being pushed by some state OSHA plans, but this posting is NOT trying to explain those methodologies. The basis for this post is to address Federal OSHA’s and EPA’s existing PHA requirement…
1910.119(e)(3)(iv) Consequences of failure of engineering and administrative controls
SAFTENG members may remember my 2013 article, PHAs and the consequences of engineering and administrative controls failing, this is Part II – better late than never.
When we come to a scenario such as “High Pressure” we need to think about our Safeguards in the order of:
PREVENT → PROTECT → MITIGATE
And in each one of those groupings, we need to apply our traditional hierarchy of controls:
ELIMINATION/SUBSTITUTION
↓
ENGINEERING CONTROLS
↓
ADMINISTRATIVE CONTROLS
↓
PERSONAL PROTECTIVE EQUIPMENT
SAFTENG members can see this graphically displayed @
http://www.safteng.net/index.php/free-section/safety-info-posts/chemical-process-safety-psmrmp/5192-what-does-a-hierarchy-of-hazard-controls-analysis-hca-look-like
For example, we have a pressure vessel with a MAWP of 300 psi. Our PHA scenario identifies a high-pressure event leading to an LOPC event via the RV. So we ask ourselves, what do we have in place that would PREVENT the HI PRESSURE scenario regarding engineering controls and administrative controls?