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Section 8; pages:
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Section 8: Over-run Prevention and Mitigation
(Page 2 of 5)
Following a series of high-profile accidents resulting from SPADs, the 'SPAD indicator' was introduced as a secondary warning device, to be placed ahead of selected 'high risk' signals. The signals involved have often tended to be platform starting signals that protect junctions. In normal circumstances, a SPAD indicator is unlit, it being activated in the event of an associated signal being passed at 'danger'. When activated, the original form of indicator displayed the word "Stop" vertically in red illuminated letters, with flashing red lights above and below [8.18]. The first example of this type was installed in 1994 at Meadowhall, the only other one being at Maryland in 1996. Later SPAD indicators installed in 1996 used a standard three-aspect colour light signal head, with a distinctive blue backboard to avoid them being mistaken as defective colour light signals when unlit. All three lenses were red, and the middle one had the word "Stop" written across it. When activated, the top and bottom lights flash and the middle light shows a steady red [8.19]. Further installations made from 1996 onwards discontinued the practice of having the word "Stop" on the middle lens [8.20]. The introduction of the Train Protection & Warning System (TPWS), which can intervene to stop a train, has almost halted new installations of SPAD indicators.
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[8.18] SPAD Indicator (original design).
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[8.19] SPAD Indicator.
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[8.20] SPAD Indicator.
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From c.1996, several more 'high risk' signals were provided with signal reminder boards some distance on their approach. The design of sign that was being installed at this time did not state the number of the signal ahead [8.21]. This type of sign was used in the Scotland Zone. There were similar signs in the Midlands Zone, and in some cases an additional plate stated the distance to the signal [8.22].
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[8.21] Signal Reminder Board.
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[8.22] Signal Reminder Board.
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The remodelling of London Paddington in 1993 provided six bi-directionally signalled lines on the approach to the station, numbered 'Line 1' to 'Line 6'. To help drivers identify which signal applied to their train, line reminder boards were installed in December 1996 showing the line name within a symbol, the shape of which was unique to that line [8.23]. The boards were mounted beside the gantry-mounted signal heads and in the four-foots, in rear of the relevant AWS magnets. These boards were removed in 2003.
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[8.23] Line Reminder Boards (London Paddington, Great Western Zone).
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Where a signal has been provided with a special surround to make it more conspicuous (see [8.24]), this is usually done in conjunction with other measures, such as the provision of additional signage in the signal's vicinity. In the case of a platform starting signal, there will typically be one or more signs worded "Check Signal" and positioned so as to be visible to a driver in the cab while stopped at the station [8.25 & 8.26].
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[8.25] "Check Signal" Sign.
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[8.26] "Check Signal" Sign.
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In December 1997, line reminder boards were fitted to signal gantries between Manchester Piccadilly and Ardwick Junction. These were large circular boards bearing the initials of the line name concerned [8.27].
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[8.27] Line Reminder Sign (e.g. "DE" = Down East line).
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From 1998, new signal reminder boards tended to have a yellow background. Two such boards were installed at Bethnal Green (East Anglia Zone) in 1998, one at 200 metres, followed by another at 100 metres before the signal concerned [8.28]. A similar board installed later in 1998 at Shenfield (East Anglia Zone) had a yellow supplementary sign [8.29].
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[8.28] Signal Reminder Board (East Anglia Zone).
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[8.29] Signal Reminder Board (East Anglia Zone).
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In March 1998, 'Station Ahead' boards of a new design were installed on the Up direction approach to Falkirk High station (Scotland Zone). Two boards were provided, one after the other [8.30 & 8.31]. The name of the station is not stated on these signs.
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[8.30] "Station Ahead" Board (Outer board).
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[8.31] "Station Ahead" Board (Inner board).
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On the Southern Region, countdown style boards [8.32] were provided to mark the approach to certain stations. The outer board, which has two columns of three diagonal stripes, is erected about three quarters of a mile to the station. The inner board, with two columns of two stripes, is located about half a mile before the station.
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[8.32] "Station Ahead" Boards ( (a) - Outer board; (b) - Inner board ).
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Position light shunting signal number W1123 is located beyond the carriage washing machine at Wimbledon Depot. Sighting of the signal is obscured by the washing machine. To draw drivers' attention to the signal, a large board worded "Beware 1123" was erected on the approach [8.33]. In April 2001, the board was replaced in a slightly different position by a similar board having much bigger text.
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[8.33] "Beware 1123" Sign (Wimbledon).
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In March 1999, a signal reminder board with supplementary sign worded "Signal Ahead" (see [8.21]) was installed at Stourbridge Junction on the Midlands Zone. Following drivers' comments, the supplementary sign was altered to specify the relevant signal number [8.34], and the triangular part of the sign was increased in size.
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[8.34] Signal Reminder Board (e.g. refers to signal number SJ89) (Midlands Zone).
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A signal having one of the worst SPAD incidence records in the whole country was signal number WS307 at Harrow & Wealdstone. This is a position light shunting signal controlling the exit from the reversing siding to the north of the station, on the DC electrified lines. London Underground Bakerloo Line trains regularly run into this siding in order to turn back before heading south again. 'Train Ready To Start' plungers are provided at the signal, but on several occasions the LUL drivers had pressed the plunger, then set off without checking the signal's aspect. The initial course of action, implemented around July 1999, was to elevate the signal to drivers' eye level and to fit a board worded "Obey Signal WS307" to the signal post [8.35].
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[8.35] "Obey Signal WS307" Sign.
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