Monday, June 05, 2006

NON-INCIDENT: Goole MCB



Someone complains to his local newspaper that the barriers at Boothferry Road MCB crossing are closed for several minutes before a train arrives. When the barriers were closed then raised to let an ambulance through, he wonders if the 'rule book'has been broken. And he wonders too why the nearby crosing at Nafferton only closes for thirty seconds.

Well, it's quite simple.

The Boothferry Road crossing is a full barrier crossing controlled by a signaller. The barriers will usually be open to traffic. The rail line will have a protecting signal set to halt an approaching train. To allow a train over the crossing, the signaller lowers the barriers to traffic and then pushes a button to confirm the crossing is clear and set the train signal to green. As this protecting signal is likely to be some distance from the crossing, the barriers are likely to be closed for several minutes.

If the signaller has not yet cleared the signal fo the oncoming train, the barrier can be re-raised (as the protecting signal is still set at red)

So, "Did the signalman break the rules by raising the barrier once it had been lowered? " No - the rule book is broken only if the barrier is raised after the protecting signal had been cleared. See the Rule Book; TW8 http://tinyurl.com/lwtm6

"Would risk to life or serious injury have been worsened if the ambulance had been delayed and not let through in order to work by the rule book? - I'm not the paramedic so I don't know about the medical severity of the case. But not letting the ambulance through would not have been a case of 'work to the rule book' - nothing in the Rule Book says that a barrier cannot be raised if a protecting signal is still at red.

"This situation suggests or almost proves under normal circumstances the barriers are lowered needlessly early." - The crossing is protected by a signal. That signal is probably some distance from the crossing - after all, what protection would it serve if it could not allow a train at speed to stop before the crossing? Therefore, the crossing will be closed to traffic some minutes before the arrival of a train. Not needlessly early, but essential.



"The barriers at the level crossing at Nafferton station near Driffield start closing barely 30 seconds before the train reaches it in both directions. A different rule book applies?". No, same rule book but different crossing type. Nafferton is an Automatic Half Barrier crossing (source: signalbox.org, http://tinyurl.com/oapkv) These are not protected by signals and are operated by the approaching train; they are set to give no less than 27 seconds warning.

There are causes for concern with level crossings. This isn't one of them.

Goole Times story: http://tinyurl.com/hws8p

Pictures:
Boothferry Road MCB courtesy of East Riding Media Library - http://tinyurl.com/poz4e
Nafferton AHB with kind permission of Neil Holmes - http://www.nh97.co.uk

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