AAHSTO says guard. (https://store.transportation.org/search?q=guardrail&categoryCode=&index=storeitem&type=storeitem&pageNum=1&pageSize=10&sortBy=Relevance&itemType=All&AspxAutoDetectCookieSupport=1)
Take note, New York.
Man you just can't let it go (https://www.aaroads.com/forum/index.php?topic=14700.msg2040987#msg2040987), can you?
Prompted by an email I got today from AASHTO.
AASHTO is also the organization that approved I-87 in NC.
New York residents say guard rail, even if the state says guide rail.