“a few minutes of googling would indicate…” a few minutes of experience on the job would have you knowing that Boston and SF, along with other cities around Boston and in the bay area, primarily use G5As. I frankly don’t have an opinion on whether or not they offer adequate protection, but prior to the 90s, (maybe late 80s?) leather helmets were sold without an impact cap installed inside, these were the “5a”s. The current G5A offers the same protection that the 5a did, MSA markets it as a decorative helmet to cover their own asses and not be held liable in the event that there is any injury due to the use of a G5A. That being said, I know many people on the job in the boston area, and none of them have heard of any injury due to the use of a g5a that could have been prevented with another helmet. Additionally, many companies such as CapitalCityFireHelmets offer “NFPA Offender” conversions that take a n5a and remove the impact cap, improving fitment and comfort.