File System Labels in RHEL based Systems

This is the command to use to check if a partition has a label.  Note: If the partition does not have a filesystem already this will error.

e2label [partition path]

This is the command to assign a new label to a partition.

e2label [partition path] [label name]

Here is the line to use in you /etc/fstab file to mount the partition by label.

LABEL=[label name] [mount directory] [filesystem type. ex: ext4] defaults 0 0

Source: http://www.cyberciti.biz/faq/linux-partition-howto-set-labels/
http://www.cyberciti.biz/faq/rhel-centos-debian-fedora-mount-partition-label/