[新疆地方标准] DB65/T 4921-2025 棘球蚴病传染源驱虫技术规范
[团体标准] ZJM-005-4921-2021 风窗玻璃刮水片
[团体标准] ZJM-004-4921-2021 乘用车盘式制动钳弹簧片
[国外标准] SAE AMS 4921L-2007 Titanium Bars, Wire, Forgings, and Rings Commercially Pure 70 ksi (483 MPa) Yield
[国外标准] SAE AMS 4921K-2006 Titanium Bars, Wire, Forgings, and Rings Commercially Pure 70 ksi (483 MPa) Yield
[国外标准] BS 4921-1988 钢铁件上的镀锌层规范
[国外标准] JIS Z 4921：1994 Measuring devices for X-ray tube voltage