Company Information

Chemically Speaking LLC is a specialty gas consulting company that can provide safety, environmental and emergency response support to users, transporters, distributors, waste disposers or manufacturers of specialty and industrial gases used in the chemical, medical, electronics and automotive industries. Chemically Speaking can also provide safety and emergency response training. Expert witness or incident investigation.


Dec 12, 2017

Just completed an exciting 2017. Many presentations and training classes (>35) throughout the world. Continuing the assist and train on highly reactive chlorine trifluoride as well as "Popping" gels that are formed from chlorosilanes. Finished Phase 1 of a research project to understand how these are formed and what can be done to mitigate the hazards. 2018 will do Phase 2 testing.

I'm excited to have been able to pull together a one day seminar on this important topic at the upcoming SESHA Conference

Reactive Silane Byproducts PDC

April 20, 2018

Eugene Ngai, Chemically Speaking LLC will chair a one day PDC on the formation of reactive silane byproducts. As discussed in his 2017 SESHA PDC on Energetic Materials, Silicon Semiconductor device manufacturers have increased their use of the more complex silane molecules such as. pentachlorodisilane (Si2HCl5), hexachlorodisilane (Si2Cl6) and octachlorotrisilane (Si3Cl8). These Si-Si or Si-Si-Si bonded molecules have a greater tendency to form reactive byproducts which in some cases are shock sensitive (aka Popping Gels). There have been reports of minor and major incidents at suppler, user and equipment supplier facilities

The Jan 2014 Mitsubishi Materials Corporation incident is believed to have been caused primarily by a  gel formed by hydrolysis of hexachlorodisilane. As maintenance workers were scraping the gel out of the heat exchanger it exploded violently, killing 5 of them and injuring 13 others.. Subsequent testing of the liquid found in the heat exchanger revealed a composition of chlorosilane polymers containing hexachlorodisilane.

To better understand how these gels could be formed, the chemistry and the energy released, two major research projects have recently been completed. Air Liquide Advanced Materials, a major supplier, funded a joint study at National Kaohsiung First University of Science and Technology (NKFUST) in Taiwan. Prof Chen who previously participated and/or conducted silane and trichlorosilane release studies from 2005-2017 will present on his findings. Over 1,000 samples were generated and tested using the BAM Fall-Hammer test to determine reactivity. He will present on his findings that were summarized in a presentation titled “Experimental Studies of Shock Sensitive Deposits from Hexachlorodisilane Exhaust”

A second supplier Dow Chemical, expanded upon their original research conducted in 2007 into a formal 18 month program that was recently completed. Mark Wanous will discuss the gel formation chemistry involved in producing shock sensitive silicon suboxides from hexachlorodisilane. It will cover silicon suboxide morphology, shock sensitivity mechanisms, factors influencing sensitivity and intensity, hazard characterization and mitigation methods

Extensive literature searches have revealed that very little research has been conducted on this issue. For both studies, the ability to grow Popping Gels reproducibly and test for reactivity was a challenge.

Both speakers will answer questions such as how are these formed and more importantly how to handle these safely after they are formed. Both studies will present information that has not been found in literature or publicly revealed.

Other presentations:

1.       Vacuum pump manufacturers experience with rebuilding pumps filled with the gel

2.       A user incident

3.       HCDS fire suppression

Discussions are also ongoing with other suppliers and users to present their incidents

May 17, 2016

I am teaching Compressed Gas Emergency Response classes all week at Global Foundries in Malta, NY where they handle many highly toxic, explosive or violently reactive materials. When I am here I always have lunch or dinner with Al Mossman who was the former President of Matheson Gas Products. He was the first engineer that Matheson hired in 1952. He was the first generation of compressed gas industry technologist in the days when handling the exotic gases was a mystery. There were many fatalities and explosions during the 1950-1980 time frame. He wrote the infamous Matheson Gas Data and Medical Treatment Handbooks. My successful career is due to his mentoring. I am now commited to passing along my learnings to the 5th generation of gas technologist so that accident history does not repeat itself.

Feb 9, 2016

I was down memory lane today. In 1989 I designed a portable pressure vessel that could be used to isolate and transport a leaking compressed gas cylinder for use at Solkatronic. AT&T our largest customer convinced me to sell them one in 1991 to their Reading, PA facility. I named these ERCV’s (Emergency Response Containment Vessel) because I did not like it being called a Cylinder Coffin. ERCV or a Solkatronic has become synonymous with these types of emergency devices (Goggle ERCV or Solkatronic). In over 25 years, there have been over 400 of these sold to users (FDNY, FBI HMRU, Taiwan EPA, etc) around the world. These have been used safely on numerous Hazardous Materials incidents involving toxic, corrosive, pyrophoric or reactive gases.

When AT&T closed the Reading facility, they donated the 5502 ERCV to the Reading Fire Dept. In over 10 years they have not had an occasion to use the unit. They contacted me to see if I could sell it to another user. This unit however will require a major overhaul, testing and maintenance before it can be sent out into the field again. I was a proud father to once again see my second “ERCV”. I brought it to the first stop in the journey to bring it back into operation for another 25 years!

April 20,2015

I'm extremely frustrated and sad. I just received e-mails from 2 retired Firefighters from Florida who sent me articles on a tragic accident a few days ago that killed a worker and injured a second. I helped them investigate a similar incident over a year ago. There has been over 4 explosions in Florida and 4 in California with companies filling cylinders without a good understanding of the hazards, yet they continue. To help spread the word, they wrote an article for Fire Engineering and I wrote the following
I had hoped that people would have learned from this

2015 was another great year. Over 20 safety and ER training classes/presentations
ANSI CGA G-13 finished the ANSI review process and was adopted as the 3rd edition

AIHA Semiconductor Gas Safety Presentation - Philadelphia, PA Jan 7, 2015

Wisconsin HazMat Conference - Stevens Point, WI, Feb 12-13, 2015

Honolulu FD HazMat - Honolulu , HI, March 3-5, 2015

Cherry Hill HazMat - Cherry Hill, NJ - Aug 12-14, 2015

MA  HazMat - Plymouth, MA Sept 16-18, 2015



Recent publications

  1.  Ngai, E., Chen, J.R. , et al, “CGA G-13 Large-Scale Silane Release Tests – Part I. Silane Jet Flame Impingement Tests and Thermal Radiation Measurement”, Tenth International Symposium on Hazards, Prevention, and Mitigation of Industrial Explosions, Bergen, Norway, 10-14 June 2014
  2. Ngai, E., Chen, J.R. , et al,  “CGA G-13 Large-Scale Silane Release Test –Part II. Unconfined Silane-Air Explosions”, Tenth International Symposium on Hazards, Prevention, and Mitigation of Industrial Explosions, Bergen, Norway, 10-14 June 2014
  3. Ngai, E., “Dangerous Gas Mixtures: Avoiding Cylinder Accidents” Specialty Gas Reporter, 2nd Qtr 2014

  4. Ngai, E. “Phosphine, From Swamp Gas to Applications in the Clean Room”, Cryogas International, 2nd Qtr 2014
  5. Ngai, E. Y., Fuhrhop, R., Chen, J. R.*, Chao, J., Bauwens, C. R., Mjelde, C., Miller, G., Sameth, J., Borzio, J., Telgenhoff, M.. Wilson, B., CGA G-13 Large-Scale Silane Release Tests – Part I. Silane Jet Flame Impingement Tests and Thermal Radiation Measurement, Journal of Loss Prevention in the Process Industries,
  6. Ngai, E.Y., Fuhrhop, R., Chen, J. R.*, Chao, J., Bauwens, C. R., Mjelde, C., Miller, G., Sameth, J., Borzio, J., Telgenhoff, M. Wilson, B., CGA G-13 Large-Scale Silane Release Tests – Part II. Unconfined Silane-Air Explosion, Journal of Loss Prevention in the Process Industries (2014),