At what point is it not a Good Service?

[moogal]

On my way home from work (around 6.15pm) I was sat on an Eastbound Central Line train, which sat in the platform at Marble Arch for around 15 minutes due to what was initially announced as a passenger alarm, and then a signalling problem at Tottenham Court Road. Throughout this, there were announcements every couple of minutes that there was a Good Service on all lines.

Given nothing was moving Eastbound and the driver announced trains were holding in platforms all the way back to Acton, that would have caused a fair bit of disruption, yet this was still a Good Service. Is there an official point at which it goes from Good Service to either type of Delays?

 

[transmanche]

There's an explanation on the TfL website.

Elsewhere, it says:

There is not a hard and fast rule as to when the service is advertised as good, minor delays or severe delays. When making this decision the line control centres have to use their judgement and have to consider various criterias which includes the intervals between trains, as well as the journey time. They must also consider the line as a whole.
​

Good service does not necessarily mean all trains are running exactly to the timetable. Everyday there are small incidents e.g. a passenger running for a train at the last minute or a small delay at a junction that can mean that the Underground service has some longer gaps.​

 

[moogal]

That's the thing though - a 15 minute gap in the peak Central Line service has a pretty big effect, with overcrowding at stations further down the line, and delays to passengers already on the trains - it's certainly not "No noticeable impact on your journey".

 

[DavyCrocket]

There is actually a complicated bit of paper based on time of day, location, direction, head ways etc.
But it depends if there are important visitors in London, managers on duty in reality.
With a 15 minute wait you should be able to get a refund. Something that I advise all customers when being regulated and ending up so late!

 

[Mojo]

Elsewhere, it says:

There is not a hard and fast rule as to when the service is advertised as good, minor delays or severe delays. When making this decision the line control centres have to use their judgement and have to consider various criterias which includes the intervals between trains, as well as the journey time. They must also consider the line as a whole.
​

Good service does not necessarily mean all trains are running exactly to the timetable. Everyday there are small incidents e.g. a passenger running for a train at the last minute or a small delay at a junction that can mean that the Underground service has some longer gaps.​

That's quite out of date now. As DavyCrocket says this varies on a number of factors and differs for each line.

In early 2012 a PDF was released under the Freedom of Information Act stating the criteria for each line: https://www.whatdotheyknow.com/requ...ing Service Status Criteria v1 6 11 11 11.pdf

 

[DavyCrocket]

However it is more than often just applied in the guess fashion that used to be used or as it suited. For example minor delays (which means you'll be delayed, but stick to your route) when there is a 20 minute wait rather than a three minute one!