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You have a railcar full of Oxirane. What is it? What is it used for? What are the chemical/ physical properties and how would you mitigate this event?

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OK Brent you win the prize!! I know what the reference material says, but how would you go to work with a leaking railcar of Oxirane?
Hi Robert,

Oxirane, better known with its chemical name ethylene oxide (EtO of EtOx), is an irritating and poisonous, highly flammable gas, normally being compressed to a colourless liquid. It has a very broad explosion range (2,5 - 100 !! % in air) and needs very little energy to light it. The gas is 1,5 times heavier than air and can be completely solved in water. The NFPA has classified it with a 3 for health effects, a 4 for flammability and a 3 for reactivity. Its permissible concentration is very low and it is not only dangerous by inhalation but can also enter the body through the skin. In contact with many compounds or when being heated, it may explosively decompose. In case of leakage a gas tight suit is prescribed (only in non-flammable concentrations!)

It is used for many purposes, some of them being the ripening of fruit, sterilisation of medical instruments, production of polyurethane and (in the form of its polymer polyethyleneoxide, PEO) as a component of many cosmetics and medicines.

If a railcar is filled with EtO, it must be a "pressure vessel" railcar. As a result of its construction, such a railcar would not be so easily damaged as regular rail cars. Damage of its appendages would be the most likely scenario.

If it would be burning, the burning gas should be left burning, to prevent explosive reignition. Cooling of the surrounding tank would be needed to prevent it from rupturing as a result of an excessive pressure buildup.

If it would only be leaking and was not yet burning, the best thing would be to dissolve the released gas in a large scale water spray, applied by water canons. The downwind area should be checked for the presence of the gas in full PPE (perhaps even in chemsuits, depending on the concentration), not only with LEL-meters, but as it is poisonous in lower concentrations, also with sensitive ppm-meters (for example a PID). Special attention should be paid to low area's like ditches and sewers, as it is heavier than air and might seep in there.

In case of application of large amounts of water, no effect on the watery environment is expected, apart from a slight pH change, so it is not necessary to contain the applied water within a makeshift d*** (apart from the fact that it would be very hard to apply such a d*** in a railway area in case it would have been needed).

Depending of where the accident location is situated, application of a lot of water will probably be difficult. If water is not present in sufficient quantities, it would be necessary to evacuate a large area (in case of an inhabited area). All ignition sources should be secured - which is nearly impossible in an inhabited area with all kind of electrical appliances.
As it is now past midnight, I stop discussing this case and go to bed. I hope hear from others on how they would handle an incident with this gas - and where they disagree with my suggestions.

Jetty Middelkoop
Hazmat Officer
Fire Dept. Amsterdam Amstelland
The Netherlands
Brent,take a look at Jetty from Amsterdams' reply. Do you agree or disagree with his actions? if you disagree, why?
jetty. thank you for your response!! I appreciate the effort and your expertise in Haz-Mat. Before I post anything I will let the other members of the group put in their comments. I loike doing different chemicals to help me stay up on my skills as well as give me different perspectives
I've handled this material on purpose. You have to be careful with EO - very easy to have a fire, very easy to polymerize it. We've had it polymerize in the cylinder before. A couple of other things to consider with this one. First, it's not the most sensitive material for a PID with a 10.6 eV bulb. Since you have to be concerned with relatively low levels, it's very important that you look up the correction factor. EO specific sensors are very cross sensitive. (If the incident occurs at a facility where it's generated or used.) I've seen glue in the hallway set one off. Another important consideration is PPE. There aren't many good gloves for handling EO. Not enough hazmat people check glove compatiblity before they go to work.

The largest use of EO is in the production of ethylene glycol (antifreeze), which is used to make polyester. When making the glycol, they generate the EO, and then convert it right in the process, when they absorb the EO into water. Most of the EO made is never shipped anywhere. The reason a hazmat person might care about that is that you can apply the lessons from how it's handled in industry. Water solubility is a good thing.

This is one where you have to find a good MSDS. The more dangerous the material, the more informative the MSDS, at least in the case of the major chemical manufacturers. Call the the manufacturer ASAP on this one!

Check out the CSB report on an EO incident:
Excellent point Dr.K especially about the gloves!!
go Brent and Jetty! Is there anything more to say. I think it was covered.....BTW Jetty are you on hazmat101@yahoocom? I have seen the name there....
Be safe
Hi Jule,

Yes, I am a forum member on hazmat101. If I sometimes do not add my name, you can still recognize me by my mail (and house) name Tijgernest - referring to my 8 cat kids and the cat statues all over the place.

Nice to meet the same hazmat colleagues on different places!

You are a great resource. It's nice to meet you.

Be safe
OK people, apparently this chemical was way to easy for you!! I guess I am going to have to approach this more analytically so that it can be a challenge to you my learned colleagues!! Next months chemical profile will definitely be more challenging, I promise!! Till then stay safe and be careful


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