Engine inspectors are called for help when an engine experiences a problem. An inspector helped Thomas when there were fish in his tank, another assisted when James became a runaway, another chastised him for staying in the shed when Percy tricked him, and another knew exactly how to stop the runaway at Toryreck (Upper Brendam in the television series). The inspectors usually wear the same uniforms as regular drivers.
- Kōzō Shioya (Japan; Thomas Goes Fishing)
- Toshio Kobayashi (Japan; Old Iron and Percy and the Signal)
- Takeshi Endo (Japan; The Runaway)
The Inspector with the Bowler Hat
- “My hat! You've sucked it through your air intake!”
- ―The Inspector with(out) the bowler hat
At the same time Class 40 came to the island, an Inspector with a bowler hat came to quieten the engines after they made a noise protesting at the Diesel. While the Diesel tried to start up, he sucked up the inspector's bowler hat into his air-intake vent, which resulted in him breaking down. The inspector complained to Sir Topham Hatt about the incident.
- Series 4 - Granpuff (cameo), Trucks (cameo), Gallant Old Engine (cameo), Thomas and Stepney (cameo), Train Stops Play (cameo) and Bowled Out
- Series 5 - Lady Hatt's Birthday Party (cameo) and Bye George! (cameo)
- Series 7 - Toby's Windmill (stock footage cameo)
- Yasuhiko Kawazu (Japan)
- His body is reused from Jeremiah Jobling's from No Joke for James.
- His head was used for a cricketer in Train Stops Play, a party guest in Lady Hatt's Birthday Party and a waiter in Bye George!.
The Black Suited Railway Inspector
- “These Engines are filthy!”
- ―The inspector commenting on James, Emily and Gordon
The Black Suited Railway Inspector was a man that came to inspect the railway for its efficiency and cleanliness, especially the engines. He also would award engines that looked their best. On the day of his arrival, Thomas and Percy have worked to hard they ended up getting covered in quarry dust. Thomas anticipated to look as good as Gordon, Emily and James but he soon expressed doubt about it.
When the big engines were at the coaling plant waiting for the inspector, James accidentally bumped a conflat which pushed a lever and coal poured onto the tracks. Coal dust spreads all over Gordon, James, and Emily. The inspector arrived with the Fat Controller and was crossed with their appearances. Then Gordon covered both men and the Fat Controller's bodyguards in coal dust after trying to clean out his funnel.
Suddenly, Thomas and Percy arrived and the inspector was so impressed by their appearances he awarded both tank engines with 1st place rosettes.
The Three Railway Inspectors
- “I wasn't sure, but now I know the Fat Controller's Railway is the best!”
- ―The Railway Inspector, Thomas in Charge, fourteenth series
The railway inspectors (known as the railroad inspectors in the US) are three men who commonly inspect the railway.
Thomas tried to impress one of them, but only succeeded in causing havoc; covering both the inspector and the Fat Controller in coal dust. Thomas was given a chance to put everything right and the inspector was very impressed with the Fat Controller's Railway. He was one of the very important visitors that attended Dowager Hatt's tour of Sodor and after party.
He returned to inspect the island once again, but with two other inspectors that look like him. When they went to inspect the Sodor Search and Rescue Centre, he and the other inspectors were not sure if having both Belle and Flynn is really necessary. However, the Fat Controller persuaded them that it's much safer with two.
Two of the railway inspectors came to inspect the North Western Railway, but proved to be grumpy and hard to impress. They eventually showed a change of heart to the railway after Thomas returned a lost watch to one of the inspectors, which was given to the inspector for working for the railway company for twenty years.
All three later returned to the Island again to observe Hugo. They expressed concern about Hugo's propeller.
Railway Inspector #1:
- Matt Wilkinson (UK; fourteenth series only)
- William Hope (US; fourteenth series only)
- Keith Wickham (UK/US; seventeenth series)
- Bob Golding (UK/US; nineteenth series onwards)
- Nobuaki Kanemitsu (Japan; fourteenth series onwards)
- Christoffer Staib (Norway; fourteenth series onwards)
- Kai-Henrik Möller (Germany; seventeenth series onwards)
- Jarosław Boberek (Poland; fourteenth series onwards)
- Jukka Voutilainen (Finland; fourteenth series onwards)
Railway Inspector #2:
- Steven Kynman (UK/US; Too Many Fire Engines)
- Keith Wickham (UK/US; Hugo and the Airship)
- Hiroo Sasaki (Japan; Too Many Fire Engines)
- Shōto Kashii (Japan; Hugo and the Airship)
- Jens Wendland (Germany; seventeenth series onwards)
Railway Inspector #3:
- William Hope (UK/US; seventeenth series)
- Keith Wickham (UK/US; nineteenth series onwards)
- Shōto Kashii (Japan; Too Many Fire Engines)
- Kunihiro Kawamoto (Japan; Lost Property)
- Tōru Akiyoshi (Japan; Hugo and the Airship)
- Andreas Birnbaum (Germany; seventeenth series only)
- Kai-Henrik Möller (Germany; twentieth series onwards)
The Island Inspector
- “Very good work, Gordon. Very good work, indeed!”
- ―The Island Inspector, O the Indignity, fourteenth series
The island inspector is a man who checks that the island is running well and looking well. Before his visit, Sir Topham Hatt insists that everything is cleaned on a day that he calls "Clean Sodor Day".
- Matt Wilkinson (UK; fourteenth series)
- Glenn Wrage (US; fourteenth series)
- Shigenori Sōya (Japan; fourteenth series onwards)
- Jarosław Boberek (Poland; fourteenth series onwards)
- Jukka Voutilainen (Finland; fourteenth series)
The Railway Coal Inspector
- “Hooray for Henry!”
- ―The Railway Coal Inspector, Henry's Happy Coal, fifteenth series
The railway coal inspector (known as the railroad coal inspector in the US) inspects coal on the railways. He once visited Sodor to study Henry's special coal, but Henry was unaware that he was a coal inspector and wanted to impress him, so he took on normal coal. The coal inspector later told Henry that he should be very proud of his special coal. He was also one of the very important visitors that attended Dowager Hatt's tour of the island and party.
- Series 15 - Henry's Happy Coal and Wonky Whistle (cameo)
- Series 16 - Express Coming Through (cameo) and Muddy Matters (cameo)
- 2012 - Henry's Happy Coal