Not surprisingly, it's found the newer rules are superior - but unfortunately only the older rules have legal standing. Yet only the Red Book contains the rules that are legally mandated for use in determining if a building is quake-prone. The newer rules (called the Yellow Chapter, or Yellow Book) carry no such weight, even though engineers trust them more. The ministry has yet to assess these impacts, though the Yellow Chapter was brought out three years ago. Very few Red Book building assessments exist.

Source: Otago Daily Times October 02, 2021 20:26 UTC