This information must be on the packages or the products as presented for retail sale. Listing this information on the container in which a good is packed for shipment will not satisfy the labeling requirement. Beside each item is the applicable NOM, if any. Laboratory test results are sent to Mexican certification bodies that issue a certificate of compliance. The certificate of compliance is presented to Mexican customs officials at the entry point into Mexico.
Numerous products are subject to regulations in addition to or in place of NOMs.
In these cases, the Secretariat responsible for the regulation must be contacted for information. Common examples are the many regulations required for the importation of medical devices, chemicals, and other products. Customs brokers and agents generally have the information about NOMs that must be complied with to import into Mexico as well as other regulatory requirements for importation. For car tires and some telecommunications equipment, Mexico and the United States have mutual recognition agreements allowing for product testing to be performed by laboratories in both countries. For some products there is a lack of test laboratories.