I agree with your analysis. It may not be possible legally for DfT to issue an authorisation or special direction to get round this, as they can only authorise a sign or marking that isn’t in TSRGD. They can’t change a regulation relating to one that is. I suppose the zig-zags together with a central warning line could be deemed a new marking.
I checked with DfT and they agree that Figure 15-1 and the text you mention in Chapter 6 are wrong. The remedy will be to change Chapter 6 in due course, not TSRGD!
TSRGD of course takes precedence over TSM where they differ.
I’ve just been looking at the TSRGD to clarify the details for the omission of the central zig zag.
The 1997 regs state
“The pattern of the central zig-zag lines may be reversed or, on a road having a carriageway not more than 6 metres wide, those lines may be omitted altogether so long as they are replaced by the road marking shown in diagram 1004 in Schedule 6 to the 1994 Regulations.”
This is replicated in the new Chapter 6
“In addition to the zig‑zag lines on each side of the carriageway, another zig‑zag
line may be laid in the centre of the carriageway. This central line may be reversed. On
carriageways up to 6 m in width, the latter may be replaced with a warning line to diagram
However the TSRGD 2016 (as amended) states
“The central zig-zag line may be reversed, or where the road is not more than 6 metres wide, may be omitted”
There’s no reference to the option of replacing it with 1004.
This is fine, but 1004 (or Item 2 Part 4 Schedule 11) is not a permitted marking within a puffin/signal controlled crossing facility/zebra controlled area. Therefore should not be used.
Has anyone else come across this?
Guess it potentially means we’ll need authorisation for this if we want to do this until the TSRGD is updated.