Butane, Flammable Liquid or LPG

[weekeseng]

I have had several persons suggest Butane is a LPG, while other maintain it is a flammable liquid. The boiling point varies from 0degC to 5degC.

Do you have any experience with Butane classification? If it is a liquid, containment would be required, is an example of an issue.

Greg Weekes

[Larry Westlake]

Butane is a LPG, not a flammable liquid. When butane liquid is released from its pressurized container, it quickly evaporates to gaseous form.

[weekeseng]

I spoke to our local Hamilton Fire marshal, and he directed me to the OFM Q&A sheets from 1997.
Per 4.1.2 of the Ontario Fire Code the butane vapour pressure is 254.55 kPa at 37.8degC. Per the fire code, any liquid with a vapour pressure not exceeding 275.8 kPa. They class it as an A1 liquid.

I thought that was very interesting to know.

The question originally came up since the butane containment is outdoors, and with a -0.5degC boiling point, it is a liquid in the winter.

[Tdmorenz]

I think it would depend on your environment you plan to use the butane in. In a warm environment, like a bakery,you would need to deal with it as a gas. If the environment was cold, like cold storgage, then it would be dealt with as a liquid. If the environment was varied or changable, summer/winter, you would need to be prepared for both possibilities.

[Mroy]

If you look up the U.N classification of butane in the transportation of dagerous goods act its in the 2.1 class which is flammable compressed gas

[weekeseng]

The current position I am taking on this issue, is to have provisions in place to classify the Butane storage as both a LPG and and flammable liquid. As part of the hazard reviews both cases will be considered regarding containment, fire suppression, spill response, isolation systems etc...

[Tdmorenz]

That sounds like a good solution. Thanks for the reply! Terry M