Obstruction Of The Line

Question 1

When don’t you need to send obstruction danger? (2)

Answer 1

1. The obstruction is beyond the clearing point.
2. There are facing points you immediately set for another direction clear of the obstruction and that line is clear up to and including the clearing point.

Question 2

For what conditions must you send obstruction danger? (2)

Answer 2

1. In an emergency.
2. If there is an obstruction on the line.

Question 3

What would your actions be if, after obstruction danger, it was acknowledged with train or vehicles proceeding without authority in the right direction? (2)

Answer 3

1. All possible actions to stop the train.
2. Acknowledge 4-5-5

Question 4

If you succeeded in stopping a train from entering the absolute block section, heading towards the signal box that sent you obstruction danger, after replying to their obstruction danger, what code must you send? (1)

Answer 4

3-5

Question 5

Other than obstruction of the line, what are the other occasions for using blocking back inside the home signal? (5)

Answer 5

1. Any movement that will be stopped on the running line.
2. Any work that will affect the safety of the line within the clearing point.
3. A work site marker board for a T3 possession.
4. An out of gauge movement.
5. Any other obstruction.

Question 6

What are the four occasions you must send obstruction danger if you become aware of a train approaching? (4)

Answer 6

1. Not received train entering section.
2. Not received trains proceeding without authority in the right direction 4-5-5.
3. Not acknowledged is line clear.
4. Not acknowledged shunting into forward section.

Question 7

What must you come to a clear understanding about with the signaller whom you sent obstruction danger to? (2)

Answer 7

1. The lines to remain blocked.
2. The lines that can be opened.

Question 8

What would your actions be if after sending obstruction danger, it was acknowledged with obstruction danger? (1)

Answer 8

Immediately tell the signal the reason for sending 6

Question 9

What must you do, and what must you not do if you receive cancelling from the signaller in the rear for a train which had been accepted before you sent obstruction danger? (2)

Answer 9

MUST - Acknowledge cancelling.
MUST NOT - Move block indicator.

Question 10

When may you allow a train to proceed towards a signal box in advance after obstruction danger has been received? (2)

Answer 10

1. You have received obstruction removed.
2. Line is clear has been acknowledged.