(a) Except as provided in subdivision (b), a retail establishment that sells, transfers, or otherwise furnishes a dietary supplement product in violation of Section 110423.2 shall not be guilty of a misdemeanor pursuant to subdivision (a) of Section 110423.2 if all of the following conditions are met:

1. (1) Every checkout clerk at the retail establishment has completed standardized training that includes, but is not limited to, the law with respect to selling dietary supplement products subject to this article, methods of easily identifying dietary supplement products subject to this article when checking out customers, and procedures for requesting identification from any customer attempting to purchase dietary supplement products subject to this article who reasonably appears to the clerk to be a minor.
2. (2) Every checkout clerk at the retail establishment is provided with training updates that cover any changes in the law with respect to selling dietary supplement products subject to this article and any other responsibilities of the retail establishment under this article.
3. (3) Every programmable checkout scanner or computer used to check out customers with purchases is programmed to identify dietary supplement products subject to this article at the checkout station. A retail establishment that does not use programmable checkout scanners or computers is not required to satisfy this condition.
4. (4) Every checkout clerk has received a written list of dietary supplement products subject to this article that are sold by the retail establishment that may be posted at the checkout station for easy access.