CSA tests products for compliance to national and international standards, and issue certification marks for qualified products. Certification marks tell potential customers and users that a product has been evaluated by a formal process-involving examination, testing and follow-up inspection-and that it complies with applicable standards for safety and performance.
For the U.S. and Canada
: A CSA mark with the indicators "C" and "US" or "NRTL/C" means that the product is certified for both the U.S. and Canadian markets, to the applicable U.S. and Canadian standards.
For gas products in the U.S.
: The CSA Blue Star indicates the product is certified to applicable U.S. standards for appliances using gas or other petroleum fuel.
Wikipedia resource: CSA International