The NSW government is requesting people who may have been exposed to asbestos to undergo medical screening.

Attorney-General John Hatzistergos this week encouraged workers to get tested for asbestos-related illnesses which are often fatal during Asbestos Awareness Week.

In a statement he said, "Occupational health and safety regulations require employers to provide health checks for employees who are exposed to hazardous substances such as asbestos or crystalline silica."

Asbestos is a carcinogenic and inhalation of its fibers can cause mesothelioma, lung cancer and asbestosis, scarring of the lungs.

Workers are able to undergo screening at the Dust Diseases Board in Sydney or on the mobile Lung Bus, which will be in Newcastle on Wednesday.

An X-ray, lung function test and examination by a doctor are included the Lung Bus checkup.

Earlier this month the state and federal governments announced they would lend $320 million to the compensation fund set up for James Hardie asbestos victims.

The free tests can be arranged by calling the Dust Diseases Board which can also organize a compensation payment.