In short all field players in the boy’s/men’s lacrosse events must have shoulder pads that meet NOCSAE performance standard, ND200.  Those shoulder pads must have the NOCSAE label.

Beginning in 2022, all field players in the boys’/men’s game must have shoulder pads or protectors that meet the NOCSAE performance standard. These products are available in the marketplace through multiple manufacturers and retailers, both online providers as well as brick-and-mortar outlets.

Beginning in 2021, all goalie chest protectors (youth, high school, collegiate, and post-collegiate) must meet the new performance standard. Goalie chest protectors that meet the performance standard could vary in product design from one manufacturer to another, but all must meet the NOCSAE ND200 standard. 

All products that meet the NOCSAE standard, ND200, must be certified by the independent Safety Equipment Institute (SEI) and include the NOCSAE Lacrosse label shown below. Consumers are also encouraged to check the SEI website (https://www.seinet.org/search.htm) under Program: Chest Protectors (Lacrosse) to verify that the specific brand is listed as approved.
 

You can learn more about this at https://www.usalacrosse.com/lacrosse-chest-protector-faq

As well as the equipment guide from USA Lacrosse https://www.usalacrosse.com/sites/default/files/documents/Safety/USAL-equipment-guide-low.pdf