30 CFR §14.7

1. (a)An approved conveyor belt must be marketed only under the name specified in the approval.
2. (b)Approved conveyor belt must be legibly and permanently marked with the assigned MSHA approval number for the service life of the product. The approval marking must be at least 1/2 inch (1.27 cm) high, placed at intervals not to exceed 60 feet (18.3 m) and repeated at least once every foot (0.3 m) across the width of the belt.
3. (c)Where the construction of a conveyor belt does not permit marking as prescribed above, other permanent marking may be accepted by MSHA.
4. (d)Applicants granted approval must maintain records of the initial sale of each belt having an approval marking. The records must be retained for at least 5 years following the initial sale.