From: Eugene Ngai <eugene_ngai**At_Symbol_Here**COMCAST.NET>
Subject: [DCHAS-L] Blog
Date: Sun, 22 Aug 2021 05:57:49 -0400
Reply-To: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**Princeton.EDU>
Message-ID: 002001d7973c$2b35ff70$81a1fe50$**At_Symbol_Here**

To All

I have received many anxious and sometimes demanding inquiries as to when my blog will be ready and posted. I can assure you that it has been a productive 3 months so far. Have written over 300 pages of lessons learned, gas history, emergency response techniques, etc. It has been an interesting exercise to go back through my files and finding information that I forgot about as well as being able to chat with industry old timers who added to my understanding of what happened in some incidents. Many old timers are glad that I’m making the effort to capture these for history otherwise their legacy knowledge would be lost forever. I’m sad however that other old timers that I have known and reached out to haven’t responded to my requests, so I know there will be many learnings I will miss.

Based on what I have written so far, I am excited that I will be covering ground that on one has done before.

For example, some of the completed summaries

1.           History of the Development of the Restrictive Flow Orifice (RFO)

2.           Explosive Gas Mixture Incidents each are over 20 pages with many historical pictures or a summary of over 40 key incidents.

Each contain numerous references that I must review again for accuracy.

3.           Others like Development of Pneumatic Cylinder Valves or The Development of the DISS Connection while shorter in length are taking time to organize and edit with credible information in order to present  an accurate and coherent summary.

4.           How many know that the reduction in germane fill density after the cylinder explosion in 1984 has prevented at least 3 catastrophic cylinder failures in recent years? yet the DOT and the UN in 2004 unaware of this history proposed an increase the fill density! I reminded them of the history and the industry Best Practice in a letter that also summarized the fatal accident with nitric oxide that reduced the fill pressure.

5.           The India silane explosion that was reported to me when I was in India in 2008 involved a release into a 2 cylinder gas cabinet, yet it was so powerful that it decapitated the operator’s  head and propeledl his body into a brick wall damaging it. The explosion completely flattened the metal gas cabinet against the wall. It was built to the US International Fire Code Standards by a US company.

6.           Prepared a summary of over 300 silane incidents. An unbelievable event was finding the gas supplier operating a silane distribution center from the basement of a motel! Even more unbelievable was the 3 instances of companies attempting to remove the cylinder valve while there was still silane in the cylinder!

In the HazMat community there have been a number of urban legends that are followed that are not based on fact.

1.           Is the LOx 30 minute rule safe?

2.           What is the 1/7 rule for acetylene? What does it mean in a response? Is it unsafe to lift an acetylene cylinder vertical?

Are these effective. Testing is underway to determine this

As these are meant to capture important safety issues/learnings, it is critical that they be as accurate as possible. I have made every attempt to verify that the key information has been documented in an investigation report, journal article or some other public document. All have been sanitized to not reveal the company or location.

I also have been fortunate to have another gas industry old timer, Ed Van Schoick review and comment on my summaries. He has 6 more months of experience in the compressed gas industry than I do! He has been invaluable in providing additional information, comments or insights, making the summaries much more powerful.

Please bear with me as I don’t want to put the blog online as I’m only 40% done. If I do it now, I’m afraid I’ll be swamped with questions or comments that would take me away from finishing. There is also a question about copyright and acknowledgement with the blog. Can someone simply download everything and publish it with them as the author? That has happened to me before.

I have also thought about what can happen to all this work if something happens to me before it goes online. As insurance, all of the files are in a Dropbox file that my oldest daughter can access. She has been instructed to publish all that I have marked done and to have the works in progress be reviewed by Ed for completeness before posting.


Eugene Ngai

Chemically Speaking LLC


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