by Ron Joseph
ASI and ANSI Color Cards and Standards
Q. Our client specified ANSI 70 grey for the finish coat. We used ANSI 70 from
a reputed paint supplier. However, the client is saying that this shade does
not match his ANSI 70 shade card and is rejecting the supply saying it has a
bluish tinge. We have the same issue with other shades such as ANSI 61 and ANSI
49. Please let me know how we can address this. Also, is there a difference
in the shade for epoxy and PU finish? And are ASA & ANSI interchangeable?
A. Many things could have happened and most of the possibilities are in fact
1- Your client may have an old shade card which has yellowed, making the shipped
color look bluer. Is the problem with the other shades (ANSI #61 and ANSI #49)
with the same client, with the same supplier, or different clients and suppliers?
A shade card could be good for many years, if well kept (no light and atmospheric
contaminants), but should be changed regularly (every few years) if used on
a constant basis, especially if used extensively under sunlight.
2- The shipped color may be wrong. How does your paint supplier verify his
color? Under what kind of light? Does he use a well kept and recent shade card
for comparison, or does he use a colorimeter?
3- The actual color of the ANSI #70 is Munsell 5BG 7/0.4 with the 0.4 for Chroma
(i.e. color saturation) indicating that this shade has a slight Blue-Green Hue
content. It is not pure grey. ANSI #49 is 10BG 4.9/0.6, slightly bluer than
ANSI #70, and ANSI #61 is 8.3G 6.1/0.5, slightly greener than ANSI #70.
4- A metameric effect: Depending on the light used to look at the shade, the
painted goods could look bluer than the reference card since they are not made
of the same colorants.
In principle, there should only a minor, or no difference between a PU color
and an epoxy one for pure grey shades but the eye is very sensitive to grayish
colors like the one you work with. Also, the surface finish could be different
and give the impression that one is darker than the other.
As for ASA and ANSI, it is the same organization. It was renamed ANSI in 1969.
Hopefully, neither your client or your supplier use a card with an ASA logo!
Cards for the three ANSI standards you mentioned can be purchased from Munsell
(GretagMacbeth) for a small cost, about 30$US per card.