Joined so I could chime in on this. Having run FrozenFaceoff.net for nearly 7 years now, we have done a lot of research on this and other regulations. As mentioned before, the red line design was introduced and mandated during the black and white TV days, and it has never been removed. There was no official end date on the use of black and white TVs so for years, this rule was left in the rule book on purpose. Over time though, color TV quietly took over nearly every household without much of a thought. Perhaps if they do large-scale 'modernization' of the rule book, they might finally remove that rule, but I do not see it happening anytime soon. So yes, it is technically against the rules to have no pattern in the red line, but only because they didn't bother to remove it, and there was zero enforcement in recent years. There may, however, be more updated mandates that go out to the teams that the public is not privy to. For instance, JetIce (who supplies paint and fabric logos for all 31 teams) confirmed to us that the NHL requires a 3 inch 'null' space between the red line and the team logo or any other team markings. The NHL also has to sign off on all designs before they are painted so reguardless of the rulebook, they are all monitored.
The first team to reintroduce the solid red line to the league (to my knowledge) was the
Chicago Blackhawks in 2006.
As for the enforcement of all ice marking regulations according to the rule book, there are other ices in the NHL that have not exactly followed the rules:
For those that would like to view more about the history of NHL ice markings, we have just finished our
NHL Rink History page. It dates back to 1917 (long before the ice was even painted white).
Hope this helped some!
