How often do the IATA and IMDG rules change?
The IATA rules are updated annually and the changes become effective January 1st each year. You must always follow the current edition of IATA rules. The IMDG rules are updated every two years. The rules are published in the latter part of each even numbered year. In the year following publication they become official, but you can still follow the earlier, two-year-old, rules. After one year, the updated rules become mandatory, until the next update is published. For example, on January 1, 2009, the 2008 edition of the IMDG Code became the official international rules, but you could still follow the 2006 edition. In 2010, you will be required to follow 2008 rules—at least until the 2010 edition is released.
