I think for businesses fire safety regulations are pretty stringent regarding the type of fire extinguishers you can use. While I appreciate the need to keep costs down, you also need to consider that fire safety is not something to safe money on. in the event of a fire you want to ensure the safety of your staff and your business.
I would suggest approaching you local fire station and asking to speak to the fire prevention officer as to what he would advise. I have used them in the past and they are vary helpful. In addition their aim is fire safety and not to sell you a product, so their advice is independent and free.
You also have to ensure that the extinguishers are maintained and recharged regularly and that people are trained in their use.
Your obligations as a business owner are specified in the FIRE SERVICES ACT, 1981 available at [broken link removed]. More info can also be got from the Fire and emergeny services planning section of the Dept of the Environment, Heritage and local governement at http://www.environ.ie/DOEI/DOEIPol.nsf/wvNavView/fsaep?OpenDocument&Lang=en,
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