AnsweredAssumed Answered

NFPA 704 dimensions

Question asked by mstromme on Aug 22, 2019

A few months ago, NFPA told me the following regarding the size of the special hazard ratings in comparison to the number ratings for NFPA 704, “The minimum dimensions of the hazard ratings (which include the special hazard symbols) are specified in figure and table so as long as they scale within those minimum dimensions, that is acceptable.”…………………….Reading that answer, it appears NFPA 704 merely requires the minimum dimensions to be met for each quadrant, but NFPA 704 does not specifically require that all the rating characters have the same height at the same time in a single square-on-point……………………So, for example, if each of the number ratings were 6 inches in height within a 7.5 inch quadrant (blue, red, and yellow), but the special hazard rating OX was 5 inches in height (just to fit inside the white 7.5 inch quadrant), then: (a) the 7.5 inch quadrant is perfect for the 6 inch numbers as it meets the minimum dimensions in the standard; and (b) the 7.5 inch quadrant also meets the minimum dimensions for a 5 inch OX because a 5 inch height OX only requires a minimum of a 6.25 inch quadrant. Since 7.5 inches is more than 6.25 inches, the minimum dimension is met for a 5 inch OX. Right?……………………….QUESTION 1: Would our scenario above (6 inch numbers in three quadrants and a 5 inch height OX in the fourth quadrant) meet NFPA “minimum dimensions” requirement for 7.5 inch quadrants on the same sign at the same time?........................QUESTION 2: Or, in the scenario of 7.5 inch quadrants with a 5 inch OX, would NFPA 704 require the number ratings also be 5 inches in height, so that the numbers and the letters are all the same height? QUESTION 3: Could you please reply in writing? Thank you!

Outcomes