Blocking Back

Question 1

What bell code is used to announce ‘Blocking back Inside Home Signal’?

Answer 1

2-4

Question 2

What bell code is used to announce ‘Blocking back Outside Home Signal’?

Answer 2

3-3

Question 3

Blocking Back Inside the home signal all occurs within the Clearing Point. But what are the 5 reasons you would use this procedure?

Answer 3

‘MIAOW’

M = Movement that will be stopped on the running line.
I = If work taking place within the Clearing Point will affect the safety of the line
A = Any other obstruction
O = Out of Gauge movement
W = Worksite marker-board for a T3 possession/work that will make the line unsafe within the work-site.

Question 4

What is the principle of Blocking Back INSIDE the Home Signal?

Answer 4

Tells the signal box in rear that you will:

Occupy your clearing point (CP)
with a train movement or something else
that would prevent you from accepting any train
under normal conditions.

Question 5

What is the principle of Blocking Back OUTSIDE the Home Signal?

Answer 5

Tells the signal box in rear that you will:

Occupy the Absolute Block (AB) section between your Home Signal and the last stop signal of the signal box in rear -
which prevents you from accepting trains under ANY CIRCUMSTANCES.