Editing Maintenance (section)

==== Predictive maintenance ====
{{main|Predictive maintenance}}
'''Predictive maintenance''' techniques are designed to help determine the condition of in-service equipment in order to estimate when maintenance should be performed. This approach promises [[Cost saving|cost savings]] over routine or time-based [[preventive maintenance]], because tasks are performed only when warranted. Thus, it is regarded as condition-based maintenance carried out as suggested by estimations of the degradation state of an item. The main promise of predictive maintenance is to allow convenient scheduling of [[corrective maintenance]], and to prevent unexpected equipment failures.<ref name="DPenn.PdM" /> This maintenance strategy uses sensors to monitor key parameters within a machine or system, and uses this data in conjunction with analysed historical trends to continuously evaluate the system health and predict a breakdown before it happens.<ref name="simap">{{Citation| last1 = Garcia | first1 = Mari Cruz| last2 = Sanz-Bobi | first2 = Miguel A.| last3 = Del Pico | first3 = Javier| title = SIMAP: Intelligent System for Predictive Maintenance: Application to the health condition monitoring of a windturbine gearbox| journal = Computers in Industry| volume = 57| issue = 6| pages = 552–568| date = August 2006| doi = 10.1016/j.compind.2006.02.011 }}</ref> This strategy allows maintenance to be performed more efficiently, since more up-to-date data is obtained about how close the product is to failure.<ref>{{Citation| last1 = Kaiser | first1 = Kevin A.| last2 = Gebraeel | first2 = Nagi Z.| title = Predictive Maintenance Management Using Sensor-Based Degradation Models| journal =  IEEE Transactions on Systems, Man, and Cybernetics - Part A: Systems and Humans| volume = 39| issue = 4| pages = 840–849| date = 12 May 2009| doi = 10.1109/TSMCA.2009.2016429 | s2cid = 5975976| hdl = 1853/56106| hdl-access = free}}</ref>

'''Predictive replacement''' is the replacement of an item that is still functioning properly.<ref name="BatRep.NYT">{{cite news 
   |newspaper=[[The New York Times]]
   |url=https://www.nytimes.com/aponline/2019/03/22/science/ap-us-sci-space-station.html
   |title=Spacewalking Astronauts Swap Out Space Station's Batteries
   |date=March 22, 2019  |access-date=March 22, 2019}}</ref> Usually it is a tax-benefit based {{citation needed|date=March 2019}} replacement policy whereby expensive equipment or batches of individually inexpensive supply items are removed  and donated on a predicted/fixed [[shelf life]] schedule. These items are given to tax-exempt institutions.<ref>such as universities and local schools, which write government-acceptable receipts</ref>{{citation needed|date=March 2019}}