Theoretic calculations show that with redundancy control the mean-time-between-failures (MTBF) of the vacuum system is doubled at least.
通过计算，冗余控制可使整个负压系统的平均无故障工作时间至少增加一倍。
2
If you know the meantimebetweenfailures and the meantime to recovery, e.g. for the hardware, use the calculations in this section.
如果知道失效之间的平均时间和平均恢复时间(例如对于硬件)，则使用这一部分中的计算方法。
3
Even though the meantimebetweenfailures of the hardware hasn't changed, the backups and scripts put in place mean that the data is safe and that you can quickly rebuild the environment, if needed.