Use disklabel(8) for this. disklabel -r drive device will give you the contents of your disk label. Look for a flags field. If you see flags: badsect, this drive is using bad144. For example, the following drive has bad144 enabled.:

    # disklabel -r wd0
    # /dev/rwd0c:
    type: ESDI
    disk: wd0s1
    label:
    flags: badsect
    bytes/sector: 512
    sectors/track: 63