Black grey is from the RAL Classic color list where it is numbered 7021. It cannot be used by name on web pages. It can, however, be applied through HTML and/or CSS via its RGB, HSB, CMYK or hex code.
Please note: RAL colors displayed on the screen are close approximates to the actual color because of the variations in brightness and contrast. The same hold true for these colors printed out on standard printers where the variations in the quality of paper, ink and the device may produce different results.