Switching power supplies are electronic devices that convert alternating current (AC) to direct current (DC) and can be found everywhere in our daily lives. During the use of switching power supply, there may be electric shock, fire and other safety hazards. Therefore, switching power supplies must meet the relevant safety requirements to ensure safe use.

Common safety requirements for switching power supplies include:
Structural design requirements
The enclosure is made of fire-resistant materials and has sufficient strength and thickness to prevent fire when electrical components are short-circuited or damaged.
Inputs and outputs should be clearly labeled to prevent incorrect connections.
The input terminal should have an overcurrent protection device to prevent damage to components caused by excessive current.
The output terminal should have an over-voltage protection device to prevent damage caused by excessive output voltage.
Electrical Performance Requirements
The input voltage range should be in accordance with the provisions of the product specification.
The output voltage should be stable and reliable, and meet the provisions of the product specifications.
Output current should meet the provisions of the product specification.
Output voltage ripple shall meet the provisions of the product specification.
Electromagnetic compatibility requirements
The switching power supply should meet the relevant EMC standards to prevent electromagnetic interference.

The following are some common safety standards for switching power supplies:
China: CCC (China Compulsory Product Certification), GB4943.1-2011 (General Safety Requirements for Household and Similarly Used AC Power Supply Equipment)
EU: CE (EU mark of conformity), EN60950-1 (information technology equipment safety)
U.S.: UL (Underwriters Laboratories certification)
When designing and producing switching power supplies, switching power supply manufacturers must comply with the relevant safety requirements to ensure that their products are safe and reliable.