From: Eugene Ngai <eugene_ngai**At_Symbol_Here**COMCAST.NET>
Subject: [DCHAS-L] Specialty Gas Safety
Date: Tue, 24 Jul 2018 17:49:30 -0400
Reply-To: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**PRINCETON.EDU>
Message-ID: 001101d42398$33ea9600$9bbfc200$**At_Symbol_Here**

Hi All:


I am a new member of this group. On and off I have seen your postings via Neal Langerman and others who I have worked with since 1985. My name Eugene Ngai, there are some other members that I also know very well. I have also answered questions for some of you over the years


I am 67 years old and in the last five years I have asked myself if I have used my knowledge to make a difference in the world. As a result, one of the key goals I have set for myself is to leave behind to this and future generations things that I have learned in the many years of working in the unique world of specialty compressed gases. I try to do this by continuing to mentor engineers and scientist in Taiwan, Korea, China and Singapore, writing safety articles, teaching safety and participating in industry/fire standards development. I have been happy donating 25% of my time and money by participating in NFPA, CGA, ISO and SESHA committees.

I would hate to think that someone was injured or died because they were not aware of lessons we learned in the last 40+ years. One sad fact is that many professionals with my background have been early retired and their knowledge and expertise is lost forever. When I started as a Chemical Engineer many years ago, there was an old timer down the hallway that would listen to my interesting ideas, chuckle and then proceed to tell me why he wouldn’t do what I proposed. That support is no longer available, where does a young professional go for guidance? An extreme example of this knowledge loss was when the UN Transportation of Dangerous Goods (TDG) in 2005 was updating the cylinder fill limits for compressed gases. They were not aware of the incidents involving germane (1984), stibine and nitric oxide (1968). These incidents caused a fatality or significant damage. As a result the gas industry lowered the fill limits of these cylinders so that they would contain the sudden overpressure if a reaction occurred. This reduction has saved the industry from at least 5 cylinder ruptures that I am aware of. Ignorant of this fact they were going to increase the fill limits based on other criteria that made sense.


I have been very fortunate during my 40+ years in the compressed gas industry to have learned from some of the best in first generation, Al Mossman, President of Matheson (Author of Matheson Gas Data Book, Compressed Gas Medical Treatment) Herb Gill, founder of Precision Gas Products, Bill Kalaskie, Superior Valve, etc. During these years I was exposed to a wide assortment of specialty gases throughout their lifecycle, R&D, manufacturing, purification, QA, emergency response, waste disposal, all with handson experience. I have been making the metal hydride gases such as arsine, diborane, germane and phosphine since 1972 at locations around the world. I was also lucky to have had the staff, company support and resources to experiment with many of the exotic gases to better understand their properties and release behavior these include chlorine trifluoride, silane, trimethylaluminum, hydrogen selenide and fluorine. Very few engineers actual get to build or operate systems. I have been a principal in the investigation of numerous compressed gas incidents including the largest release of arsine (65 lbs) in 2001 and the U of Hawaii explosion 2016. I have been given a “gift” in life. People actually pay me to do things I want to do plus pay my expenses and research. Does this get any better?


I have also on a part time basis, teaching and advising public and private HazMat teams around the world on compressed gas emergency response since 1990. This proved to be of value in the U of Hawaii investigation as I had trained HazMat 1, Honolulu FD exactly a year before. They made entry into the lab after the explosion and were able to share with us their initial assessments, pictures and reports. I can reach out to many HazMat teams in the US and get an immediate answer to a problem.


Over these years I have maintained a large data file on incidents involving specialty gases and continue to have others that add to this by sharing details of incidents with me. I try to distill these into a non confidential summary of lessons learned to share.

As a consultant, I have had the opportunity to inspect and teach safety at many universities, manufacturing sites, users and laboratories where I find many common compressed gas safety problems or misconceptions. In my goal to pass along my knowledge, I will try to publish every week on this forum a key compressed gas safety fact that I have found and why they are important..


Many of you probably have questions as well. I would be happy to answer them as long as it doesn’t take more than 10-15 minutes of my time. I do this all the time with students that may go back as far as 30 years.


The link below is my first safety alert on a current problem involving  hexachlordisilane.



Eugene Ngai

Chemically Speaking LLC


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