I didn't find the policy of Hyundai, but I have several others.
Acer: No more than four defective pixels per million on a given display.
Apple: Conforms to ISO 13406 standard for pixel anomalies (I guess Google could clear up what that means).
BenQ: Five defective pixels or one defective pixel in the center of a 3x3 grid.
Dell: Six fixed pixels or "several fixed pixels in a small area of the screen."
HP: Three bright subpixel defects, five dark subpixel defects, five total subpixel defects, or 0 full pixel defects.
LG: Two defective pixels in any quadrant of a 2x2 grid.
NEC/Mitsubishi: Varies according to display size.
Samsung: 0 defective pixels.
Sony: Conforms to ISO 13406 standard for pixel anomalies (see above).
ViewSonic: Seven defective pixels.
CPU Magazine, May 2005 issue, page 20 (comments my own)
If you're just wanting to test your monitor to be sure it is working properly, follow this link. It goes to a page of monitor test downloads:
Hopefully some of this helps.