The Ministry of Business, Innovation, and Employment says there are still problems with handling asbestos, for workers in Christchurch involved in its rebuilding.
More than 350 people attended a two-hour course on Friday to learn more about the potentially lethal substance, and how to deal with it safely.
Spokesperson from the ministry's health and safety group Kathryn Heiler says the majority of contractors are competent, but there are some who aren't identifying asbestos before starting work on a building.
Ms Heiler says the ministry has received about 80 complaints about asbestos since the earthquakes.
She says this Friday morning's workshop covered a variety of topics, including how to identify asbestos and what protective equipment should be worn.
Ms Heiler says more workshops will be held over the next few months.