Dangers of Overhead Lines

1
05/96
HSE Bulletin

Committed to
Safety

Dangers of Overhead Lines Background On 10 June
1996 a tractor trailer unit loaded with a
Caterpillar 583 pipe layer contacted an overhead
power line as it travelled between Fahud and
Yibal. Only minor damage was sustained
to the 33 000 volt power lines however the
incident could have caused a fatality. People
have been electrocuted and killed in Oman when
cranes or high vehicles have touched overhead
power lines. Recommendations to prevent
recurrence To prevent a similar incident from
happening again it is essential that the height
of each truck load is verified prior to
commencing the journey. Goal posts are usually
placed on PDO roads where overhead lines cross
the roadway. These barriers are placed to enable
drivers to check that they may pass under
overhead power lines safely. If goal post
barriers are not provided drivers of vehicles
with loads higher than five meters must not pass
under the overhead line unless they have been
issued with a Clearance Certificate. Supervisors
of high loads must ensure that they are aware of
height clearance along the route and that the
drivers are adequately briefed. Supervisors
should apply for a Clearance Certificate from the
Asset Custodian before allowing loads higher
than five meters to proceed on routes that have
over head line crossings that have not been
fitted with goal post barriers. The risks
involved with transporting high loads should be
discussed at tool box talks and safety
meetings. Learning Points Transporting loads that
are higher than normal can be hazardous. The
hazard can be presented to personnel equipment
and even the environment should the load come too
close to the overhead line. In many cases power
in the overhead line can "jump" just by coming
too close. The load doesn't have to touch the
power line for an electric arc to occur. Contact
with an overhead power line can result in burns
to workers fires fatalities and extensive
damage to the equipment. Additional losses such
as oil deferment equipment shutdown and power
failures can result from a power line contact.
Transporting high loads is risky business and
extra care needs to be taken when approaching
overhead lines. For more information on the
incident contact AEF/2 on 67-3372. The contents
of this Safety Alert should be communicated to
all PDO and Contractor employees by Section Heads
and Contract Holders. Records of the discussion
should be maintained for review.