| 1. | Four required per backflow preventer
每个防回流阀需要四个。 |
| 2. | For use with backflow preventer test cocks to protect from damage
用于防回流阀测试旋塞，防止受到破坏。 |
| 3. | The system should be flushed before the backflow valve is installed
在安装回流阀之前系统应该进行冲刷。 |
| 4. | Installing a backflow preventer in a pit or vault is not recommended
不建议在坑内或拱顶内安装防回流阀。 |
| 5. | Especially made for testing all reduced pressure zone backflow preventers
专用于检测所有减压区防回流阀。 |
| 6. | A check valve may be required ahead of the backflow preventer
此时在防回流阀前面可能需要安装一个止回阀。 |
| 7. | Also , mechanical backflow preventers and air gaps can be bypassed
此外，机械式防回流阀和气隙可以作为旁路。 |
| 8. | Certified testers of backflow assemblies must conduct this test
这种测试必须由有资格证书的防回流阀总成检验员进行。 |
| 9. | Certified testers of backflow assemblies must conduct this confirming test
必须由有资格证书的防回流阀检测人员进行这种确认检测。 |
| 10. | Backflow preventer manufactured from 300 series stainless steel for corrosion resistance
防回流阀采用耐腐蚀的300系列不锈钢制造。 |
