Attribute: Vertical clearance
Attribute type: F
The vertical clearance measured from the plane towards the object overhead.
ENC Condition:# Must be encoded for BRIDGE objects over navigable water that are non-opening.
INT 1: ID 25-28;
M-4: 380; 380.1; 382; 383;
Minimum Value: 0
Unit: defined in the HUNI subfield of the DSPM record or in the HUNITS attribute of the M_UNIT meta object class, e.g. metre (m)
Resolution: 0.1 m or 0.1 ft
7.6 for a vertical clearance of 7.6 metres.
In the case of cables carrying high voltages an additional clearance of from 2 to 5 metres may be needed to avoid an electrical discharge. When known, the authorized safe clearance (known in the UK as the Safe Overhead Clearance) which is the physical clearance minus a safety margin shall be stated. (IHO Chart Specifications, M-4).
See also 'vertical clearance safe'.