I have started a memo concerning lightning protection for offshore facilities. Please feel free to comment on subject below.
Purpose:
This document is intended to address the need for lightning protection on offshore facilities
Summary:
Offshore facilities are generally all steel structures of which all major components are welded firmly to deck. This inherently provides solid grounding to superstructure of all vessels, towers, skids, buildings, etc.
In my past experience we never installed lightning protection offshore due to the inherent all steel design of facilities. I have also consulted with other senior electrical engineers about this subject and we have all came to the same conclusion that lightning protection is not required on offshore facilities.
If lightning were to strike any location on platform the structure itself would rise to equal potential thus causing no harm to personnel or equipment.
API RP 2003
5.4.4 Tank Ships and Barges
In general, a steel ship or barge can be considered to be
protected against damage from direct-stroke lightning if the
masts and other projections are adequately grounded to the
hull. On ships whose hulls are constructed of wood or other
insulating materials, a ground connection from the mast or
other projecting metallic structure to a copper plate below the
water line should be provided. Radio antennas should be provided
with a lightning arrestor or with facilities for grounding
during electrical storms.
Ships and barges are subject to indirect induced currents
and corona effects, which can cause sparking. It is advisable
to suspend loading or unloading operations and to close all
tank openings when severe lighting storms are in the vicinity.
See the OCIMF International Safety Guide for Oil Tankers
and Terminals for speciÞc information on effective protection
of tanks and barges.
lightning protection for offshore facilities 2
Re: lightning protection for offshore facilities 2
