Defining high speed rail ... medium speed rail .....

[ozbob]

It is important to define what is meant by Fast rail, Medium speed rail and High speed rail.

It is generally accepted that fast rail is in the range of top speeds of around 160 - 200 km / h.

High speed rail is greater than that.  However Laird did suggest in his article ( https://theconversation.com/lets-get-moving-with-the-affordable-medium-speed-alternatives-to-the-old-dream-of-high-speed-rail-95854 ) that medium speed rail speeds he was referring to was 160km and 250km/h, which has also been used elsewhere ( https://www.linkedin.com/pulse/medium-speed-train-market-analysis-bedy-kharisma/ ).

But there is no absolute definition of any of this.

I think many confuse Fast Rail with High Speed Rail (HSR).  Maybe it is better to use medium speed rail (MSR) for 140 - 250 km/h and > 250 km/h as high speed rail.

I think it is less confusing.

What is more achievable in the Oz context is MSR as opposed to HSR, however HSR might be achievable down the track so to speak.

[ozbob]

Definitions:

Suburban rail and regional extensions of those systems, speeds: up to 140km/h

Medium Speed Rail (MSR) speeds:  140 km/h to 250 km/h

High Speed Rail (HSR) speeds: > 250 km/h

Terms such as Fast Rail and Very Fast trains are confusing.

Fast rail is medium speed rail.

Very fast trains is high speed rail.

Regional rapid rail is medium speed rail.

[#Metro]

I've posted this elsewhere. There does need to be official standardisation otherwise it will end up like the term 'Metro', which could be anything.

TERM......SPEED
VLSR - Very Low Speed Rail - 50 km/hr and under
LSR - Low Speed Rail - 50 km/hr and up to 150 km/hr
MSR - Medium Speed Rail - 150 km/hr up to 250 km/hr
HSR - High Speed Rail 250 km/hr to 350 km/hr
VHSR - Very High Speed Rail - anything over 350 km/hr

More weight should be put on average speeds for the service. e.g. Acela would be classed as MSR not HSR.

[ozbob]

The problem is some people referring to fast rail, when they really mean high speed rail.

No, as far as I am concerned we only need:

MSR and HSR.  Anything else is too complicated.

[#Metro]

Perhaps, but it does make it plain that what we have mostly got is... LSR & VLSR  

"What we cannot speak about we must pass over in silence." (What we cannot speak, we cannot think).
https://plato.stanford.edu/entries/wittgenstein/