Michael Kottek1, David J Kilpatrick2. 1. PO Box 733, Ocean Grove, VIC 3226, Australia Occupational Hygiene Assessments Pty Ltd, PO Box 6016, Cromer, VIC 3193, Australia mkottek@diosma.net. 2. PO Box 733, Ocean Grove, VIC 3226, Australia Occupational Hygiene Assessments Pty Ltd, PO Box 6016, Cromer, VIC 3193, Australia.