Yorkshire Ambulance Service said there were three thefts reported last year, six in 2016 and five in 2015. There were another three in 2014 and four in 2013.
CRIME: Teenage boys hunted over robbery in SheffieldAcross Yorkshire as a whole there were 57 thefts, with defibrillators, sat navs, drug bags diesel and mobile phones among the items stolen during the raids.
APPEAL: Woman dragged to ground and kicked by gang of women in Sheffield streetPOLICE: Man wanted over burglary, drug and driving offences in SheffieldJackie Cole, Yorkshire Ambulance Service NHS Trust's Divisional Commander for South Yorkshire, said: "Thefts of equipment from our vehicles and stations can have an impact on our ability to respond to emergency calls.
"It takes vehicles off the road and also costs us valuable money to replace stolen items.
"The satellite navigation systems we use in the ambulance service are specific to our vehicles and are of no use to members of the public. We also immediately block any mobile phones which are stolen, so they are useless for making and receiving calls."
She added: "Our dedicated staff work extremely hard to deliver the best possible service for patients and having vital equipment stolen is a problem that they should not have to encounter. "We will always prosecute and seek compensation from anyone causing criminal damage to our vehicles and equipment.
"We would also encourage anyone with information about a theft to contact the police."
Call South Yorkshire Police on 101 or Crimestoppers on 0800 555111.