The main purpose of safety certificate which focus on keeping people safe while using products properly.
Due to the different standards of each country, the required certificate must be determined in accordance with the product where it applies to use.

For example, for AC/DC power supplies, DC/DC Converters to use and install in different category of equipment, it requires to comply with different safety specification, . i.e.  ITE for 62368-1, Medical for 60601-1 and Railway for 50155.