Book about industry - ethylene oxide 4

[dogtop]

Dear Eng-Tipers,

I am searching for a book, or books, about ethylene oxide and products made of it. I am looking for a book that contains technology description, properties of the material, materials of construction, major producers, major consumers, safety, etc, etc ... etc.

Does such a work exist?

Regards and happy holidays to ALL.

 

[lastone]

Such a work does exist. The best part is the best one out there is free and on the web. The book is called "Ethylene Oxide". It is made available through a collaboration of the major industry producers of EO. Just type "

http://www.ethyleneoxide.com"

and there you are. If you are going to be working with this chemical its a very good idea to learn every single thing you can about it. Enjoy.

 

[MJCronin]

dog....

I have used and read the EtO book and have found it to be excellent....

EtO is very nasty, explosive stuff......before you begin an extensive project involving the storage, use and transfer of this material, consider hiring a consulting engineering firm that specializes in ethylene and propylene oxide systems.

My thoughts only...

-MJC

 

[kenvlach]

Ethylene oxide was extensively used as a sterilizing agent (especially, for heat- and moisture-sensitive products) by the medical implant industry until its use was effectively banned within the US by OSHA, the EPA and Air Pollution Control Districts. Emissions have thus been decreased by 90% since 1994.

Lots of information on ethylene oxide -- description, uses, health effects, manufacturers, regulations, Toxics Release Inventory overview, etc. and government links at

http://www.nsc.org/library/chemical/Ethylen0.htm

"Health effects
Ethylene oxide is classified by the Occupational Safety and Health Administration (OSHA) as an occupational carcinogen and as a "de minimis" carcinogen, meaning that the minimum amount of the chemical set by OSHA is considered to be carcinogenic. It is listed on EPA's Toxic Release Inventory (TRI) as a de minimis carcinogen. It is also defined as a substance "which may reasonably be anticipated to be a carcinogen" by the U.S. Department of Health and Human Services' National Toxicology Program's Fifth Annual Report on Carcinogens...
OSHA PEL: TWA 1 ppm 5 ppm [15-minute Excursion]"
[The limit in California is 0.1 ppm, so OSHA may follow suit sometime after 2008]

Another information site is

http://www.epa.gov/pesticides/factsheets/chemicals/etofactsheet.htm

"Currently Registered Uses for Ethylene Oxide
EPA regulates ethylene oxide under the Clean Air Act; Comprehensive Environmental Response, Compensation, and Liability Act; Federal Insecticide, Fungicide, and Rodenticide Act; Resource Conservation and Recovery Act; Superfund Amendments and Reauthorization Act; and the Toxic Substances Control Act..."

So of course, industry has to use BACT (Best Available Control Technology) to limit emissions. However, if you're the government, you can play with the rules. At the latter site, read "Emergency Use of Ethylene Oxide in Anthrax Decontamination."

Ken

 

[itsmoked]

I don't know what you are talking about kenvlach. There are dozens of ETO sterilizers in the USA. It is the only way to sterilize many types or products that don't take kindly to steam or radiation.

Every nut in every candy bar you have ever eaten has been sterilized by ETO. All sterilized seasonings are sterilized by ETO. Most medical products with plastic in them must be ETO sterilized. You aren't going to be radiation or steam sterilizing a heart pacemaker.
Contact lenses are ETO'd. I'd guess about 50,000 products require specifically ETO sterilization.

I have personally installed FDA approved ETO Sterilization Controllers on about 30 US chambers.

Yes... the stuff is nasty.
Yes... It's very flammable. We designed a data logging unit that rode thru the chambers and had to deal carefully with ETO which is the second most flammable gas. Only hydrogen is more flammable.

Yes a sloppy workers have been damaged by doing things like opening chamber doors early with cigarettes dangling from lips.

Yes a lot of systems that scrub the ETO from the system exhaust to form Ethylene Glycol have blown sky high along with half the facility.

Yes a lot of flare stacks designed to burn all escaping ETO have blown up.

ETO facilities run gas chromatographs in all rooms of interest.

ETO sterilized products must remain for some time in the POST Sterilization room to allow out gassing and for the extremely reactive ETO to finish converting.

Fewer people have been killed by the ETO process than have been killed by the radiation process.

Well that's my input.. I worked for about 12 years in the field. Any questions? Shoot.

By the way there are very few things that ETO doesn't attack. It attacks most the stuff sterilized by it but luckily the Cooties die long before the products are materially damaged.

 

[kenvlach]

OK, my wording "effectively banned" was overly strong. In order to use EtO (in my part of California, at least) you have to verify to the APCD's satisfaction that no usable substitute exists, submit engineering control plans for construction permit, testing afterwards for operating permit, etc. The emissions controls mentioned by itsmoked show that it has become much more costly to use EtO within the last 15 years. So, substitution has occurred whereever possible.
Ken

 

[kenvlach]

Perhaps one of itsmoked's aforementioned blowups:
An ETO explosion in 2004 is still being investigated by the U.S. Chemical Safety Hazard and Investigation Board (CSB):

"CSB Investigating Ethylene Oxide Release and Explosion at Sterigenics Facility in Ontario, California"
August 19, 2004

At approximately 3:00 p.m. on August 19, 2004, an explosion occurred inside an ethylene oxide sterilization chamber and an associated thermal oxidizer at the Sterigenics facility in Ontario, California. Four employees suffered minor injuries and the facility was rendered unusable.
..."

http://www.csb.gov/index.cfm?folder=news_releases&page=news&NEWS_ID=180

 

[itsmoked]

Yikes... Reads very much like others I have heard about.

It appears to be very difficult to burn the the venting gas safely due to its extremely broad flammability. I think flame paths head right back down to chambers during the slightest change in variables. Say a check valve is slow or a mixture is a little rich or a pump is worn or the wind is blowing harder or from a different direction.. Subtle reasons. (This is just my thoughts.)

Thanks kenvlach.

 

[Jaimit0]

kenvlach/itsmoked: Do you know if the root cause of the Ontario EO explosion was determined? I would appreciate any info you may have. Thx!! Jaimit0

 

[itsmoked]

Sorry I have no specifics. I can only speculate. They said that it was associated with the chamber and the "thermal oxidizer".

The chambers have no ignition sources associated with them and usually never go bang on their own. Oxidizers do have ignition sources, up to and including natural gas fired burners. Others try to react the ETO to produce something else often Ethylene Glycol for sale to antifreeze types.

If the mixtures get to rich or too much reactant (ETO) gets to the scrubbing system you can have temperatures rise to the ignition temp and that's all she wrote.

It was stated that this occurred during maintenance so perhaps a whole chamber load of ETO was vented quickly out to the scrubber, something that never normally happens.

Normally a chamber is very slowly shifted, (pressure wise), because if you just yank a vacuum or blow the vent value you will burst all the customers boxes and gas permeable membranes etc. This is usually meticulously avoided for obvious reasons. However in a maintenance realm instead of carefully crafted process recipes being guided by control software you can have staff saying "okay dump the chamber, just open the valve 100% because we have an empty chamber." Well the scrubber may not expect this or be sized for it. Boom.

They may never actually ever figure out what exactly happened.

Keith Cress
Flamin Systems, Inc.- <

http://www.flaminsystems.com>

- kcress@<solve this puzzle>

 

[Jaimit0]

Thanks for the feedback.
The CSB press release stated: "the EO chamber where the explosion occurred was undergoing mntc at the time of the incident". Although this may not be entirely accurate, a priori, it rules out the oxidizer and brings in poor prep for the mntc or hot work. But as you say, the exact cause may never be determined.
If interested, I'll let you know any further findings.

Jim Fisher, Pharmaceutical Systems, Inc. jfisher@pharmsystems.com