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.
News
Jan 16, 2021 Last week there was a serious incident involving Tetramethylammonium Hydroxide (TMAH), a chemical that is widely used in the Semiconductor Fab. It is not known what the final outcome is of the 6 individuals that were exposed, 2 were serious. In many large Fabs TMAH is piped throughout the facility at various concentrations. Of all the reactive/pyrophoric or toxic chemicals used in the Fab, TMAH is one of the top 5 that I have a concern with as there appears to be no effective medical treatment protocol. I spoke to Dr. Wu at my 2008 training class on Trichlorosilane Safety and ER in Taiwan. As a consultant to the Taiwan Poison Control Center he has been involved in TMAH incidents, 3 of which were fatal. He spoke of one in which a worker was alone and was splashed with a 25% solution. He immediately went to the safety shower. He was found 15 minutes later barely conscious. Prior to arrival at the hospital he went into cardiac arrest. He was resuscitated but he slipped into a coma and died 8 days later. High concentration (25%) exposure of 7% of the body is fatal! Even lower concentration can also be Park et al., J Occup Health, 2013 • 39 yr old male splashed 8.75% TMAH on his hands, arms and legs • 12% body surface area affected • Continued working and went to the shower room 25 mins after the spill • He was found dead outside the shower ~60 mins later • Second degree burns on skin IBM Medical and Safety professionals conducted a detailed review of incidents as well a sponsored extensive animal dermal exposure testing. They presented their findings at the 2011 Semiconductor Environmental Safety and Health Association (SESHA) Conference with an update in 2018. I have summarized the LG Display incident as well as the 2011 IBM presentation to educate those that have limited knowledge of TMAH. The presentation was updated in 2018. It can be downloaded for free to SESHA members. Membership is free. My summary can be found in Files
Aug 2020 I had the pleasure of collaborating with my daughter Courtney (PhD in Chemistry Education) on a peer reviewed article for the ACS Journal of Chemistry Education "Compressed Gas Safety At The University". She is a gifted writer who was able to take my Engineering mumbo jumbo and put them into coherent and meaningful sentences. It was interesting to work with a child who is now my peer. J. Chem. Educ. 2021, 98, 1, 57–67 July 22, 2020 https://doi.org/10.1021/acs.jchemed.0c00138 Feb 2020 Happy to report that I just received my 6th US patent. No. 10550002 “Method for treatment of hexachlorodisilane and hydrolyzed product”, Feb 4, 2020 Feb 9, 2020
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.
Jan 21, 2019
Chemically Speaking LLC is celebrating 10 Years on Feb 1, 2019! A milestone! I have had many compliments on the name but I can’t take credit for this, Courtney said Dad you can’t have a boring name how about this? It fits! I am now 67 and could easily retire but yet here I am with a full schedule!
During these 10 years I have been having great fun! I have never had to advertise, yet people find me. 2019 is already booked through April with lots of interesting projects on some cutting edge research or University Research projects that will change our lives. Of course. I’m still looking at blowing some things up in the interest of science! Hope to recreate events leading up to 4 fatal accidents with organometallic materials.
Am also looking at buying a small technology company with many patents for a client. What’s nice is I’m at the point where I can tell someone to stuff it. Did that twice in 2018! Felt good!
Travelled just under 2 million miles to exciting places around the world. I continue to do research on chemical safety and plan to do more in 2019. It’s nice to have a sense of purpose in life. Put together and chaired a seminar in April that had 70+ people worldwide pay $450 to attend on a highly reactive chemical that killed 5 in 2014 and destroyed a manufacturing plant in the US. Will do another seminar this year based on another year of research paid for by 2 customers.
One patent, 5 peer reviewed articles plus 6 non peer reviewed articles. Convinced 12 companies to chip in $500,000 of money and equipment to do 4 days of testing in New Mexico. Got them to fund some more testing a year later. Trained or presented to over 8,000 Firefighters or University employees.
Investigated 5 serious explosions and determined root causes of these during this time. In many the damage was so severe that it was a challenge to determine what might have happened.
There is nothing more rewarding than to pass on or discover new items that can help to protect people. I see many students from classes 10+ years ago that are still very eager to learn. Donate 20% of my time plus $20,000 every year to train this generation.
Getting paid a lot of money to do all this is icing on top! I would do most of this for nothing because its so interesting.
I am a very lucky guy!
Oct 20, 2018 Great news! After a year of ground breaking research on the shock sensitive gel formed by Hexachlorodislane, Prof Chen and I have been issued a Taiwan Patent "Process for Treatment of Hexachlorodislane and Hydrolzyed Product", Taiwan Patent I634939 Sept 11, 2018. This gel was involved in a fatal accident in Japan that killed 5 and injured 13. No one knows how to handle it. Sept 2018 Accidental Reaction of Metal Alkyls (Organometallic compounds) with Moisture or Air Causing a Cylinder to Rupture Metal Alkyls (Organometallic) are finding increasing use in the Silicon Semiconductor Fabrication Industries. The most commonly used are: Trimethylgallium (TMG) Trimethylaluminum (TMA) Trimethylindium (TMI) Diethylzinc (DEZ) The III-V device manufacturers typically dispense these from a cylinder configured to function as a bubbler (A carrier gas is bubbled through the liquid/solid to be saturated with the vapor). To maintain a precise concentration the cylinders are immersed in a heated or chilled water bath (glycol). These are located within the tool (MOCVD) and are maintained under positive pressure. A leak if it were to occur it would be outward causing a fire. The silicon device manufacturers on the other hand dispense Trimethylaluminum by pulling a vacuum on the vapor space of the canister in the ALD process (Atomic Layer Deposition). Due to the larger volumes used, a small host container is located close to the tool in the cleanroom. This is constantly filled by larger bulk supply and process containers located in the subfab, these are pressurized to fill the canister. Diethylzinc is used to grow a transparent conductive layer for a thin film photovoltaic cell. The use of Metal Alkyls is forecasted to increase dramatically for all uses. Pyrophoricity (spontaneous ignition) and fire is probably the most well-known hazard characteristic of these key organometallic compounds. A fire is commonly encountered during accidental release of Metal Alkyls into air. Most current safety precautions for handling these materials are associated with the pyrophoricity. Violent reaction with liquid water is also a well-known problem. The hydrolysis reaction may generate sufficient heat to trigger a self sustained decomposition reaction. Can the ingress of air or water in the ALD process trigger a self sustaining decomposition reaction that ruptures the container? These Metal Alkyls are also thermally unstable. Heat can trigger a decomposition reaction. Imagine a spill around a container that is on fire water cannot be used to cool the container or put out the fire. There have been 5 known fatalities plus numerous injuries due to these causes that ruptured the container Known incidents TMG container explosion after glycol is sucked in (date unknown) TMI container explosion after air sucked in, Dec 11,1998 (2 injuries) TMI container explosion after it was heated to decomposition temperature, 2012 (1 injury) TMI container explosion from moisture from valve, Oct 9, 2013 (1 fatality, 1 injury) TMA container explosion after air is sucked in, Jan 7, 2016 (4 injuries) TMI explosion, cause unknown, Feb 16, 2017 (3 injuries) TMI container explosion after air is sucked in, May 2018 (2 fatalities, 1 injury)
TMI container explosion, cause unknown, Sept 19, 2018 (1 fatality, 3 injuries)
A test program is to better understand what can happen with Trimethylaluminum in a typical ampoule (1 liter) in a worst case incident has been proposed for 2019. Open valve to suck in air. Drip 5 cc of water into container. If any of the tests do not trigger a decomposition reaction, heat container to decomposition temperature
The test program will Video from 4 angles High speed video of container rupture Canister pressure measurement Temperature measurement Overpressure sensors in a x-y grid
Test Directors: Prof. Jenq-Renn Chen, Department of Safety, Health and Environmental Engineering, National First University of Science and Technology, Kaohsiung, Taiwan. jrc@nfust.edu.tw
Eugene Ngai, Chemically Speaking LLC, Whitehouse Station, NJ 08889, eugene_ngai@comcast.net
Recent publications
|
liquid nitrogen, compressed gas safety,silane safety, silane safety training, ngai, gas consulting company, emergency response, environmental response, industrial gases, specialty gases, safety and emergency response training, acetylene, ammonia, argon, arsine, arsenic pentafluoride, boron trichloride, boron trifluoride, bromine trifluoride, butane, carbon dioxide, carbon monoxide, carbon tetrafluoride, carbonyl sulfide, chlorine, chlorine trifluoride, cyanogen, cyanogen chloride, diborane, dichlorosilane, diethyltelluride, disilane, ethylene, ethylene oxide, fluorine, germane, germanium tetrafluoride, helium, hexafluoroethane, hydrogen, hydrogen bromide, hydrogen chloride, hydrogen cyanide, hydrogen fluoride, hydrogen iodide, hydrogen selenide, hydrogen sulfide, hydrogen telluride, methyl mercaptan, methane, monochlorosilane, neon, nitric oxide, nitrous oxide, nitrogen, nitrogen dioxide, nitrogen tetroxide, nitrogen trifluoride, oxygen, oxygen difluoride, pentaborane, phosgene, phosphine, phosphorus oxychloride, phosphorus pentafluoride, propane, silane, silicon tetrachloride, silicon tetrafluoride, stibine, sulfur hexafluoride, sulfur tetrafluoride, trichlorosilane, triethylaluminum, TMAH, trimethylboron, TMB, trimethylgallium, TMG, trimethylsilane, trimethylaluminum, TMA, trisilane, trisilylamine, tungsten hexafluoride, xenon, inorganic acid gases, inorganic base gases, metal hydride gases, halocarbon gases, amine gases, freon gases, hydrocarbon gases, oxidizer gases, pyrophoric gases, pyrophoric liquids, highly toxic gases, corrosive gases, liquefied gases, inert gases, water reactive liquids, dangerous when wet liquids, chlorosilane, methylchlorosilane, unstable gases, cryogenic liquids, explosive gas mixtures, semiconductor gases, TFT-LCD gases, PV gases, Photovoltaic gases, CIGS, MOCVD gases, DOT Special Permit, Cylinder containment vessels, ERCV, Cylinder coffin, Cylinder Salvage Vessel, Solkatronic 5502, NFPA 55, NFPA 400, CGA G13, FM 7-7, cylinder rupture, cylinder explosion, cylinder valve