Following a question received from a quarantine officer in a SE Asian country regarding the relative efficiency of various diameters of copper tubing used in methyl bromide vaporisers and an on-the-job experience of a vaporiser with large diameter tubing which did not completely volatilise the liquid methyl bromide, an investigation into the relative efficiencies of copper tubing of various internal diameters and lengths was carried out.

It was shown that, within practical operational limits, the smaller the diameter of the tubing the more efficient it would be at transferring heat from the water bath to the liquid methyl bromide.  It was also shown that larger diameters, as well as being less efficient at heat transfer, could also allow the liquid methyl bromide to pass through the system at a rate too fast for full volatilisation.

ISPM 15 Fumigation, designed to prevent timber pests on timber packaging material, pallets and dunnage, from crossing borders from country to country, is consistently failing.

The ISPM 15 standard has been recently amended in an effort to increase the success level, but the amendments will probably lead to increased use of methyl bromide, with no improvement in fumigation efficiency.

For the last four years specialist Australian fumigation trainers have been instructing members of the fumigation industry and Government Quarantine Officers in the countries of our Asian trading partners in the correct methods of fumigation. This has been done in order to ensure that exotic pests that may constitute a threat to Australia are not imported into that country.