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fects of direct and indirect lightning strikes and maintenance cludes recommendations for the intervals between the com-
and repair measures should be taken, if required. A report of plete test of a lightning protection system under average envi-
the lightning protection system containing the design criteria, ronmental conditions. The test intervals specified in regulatory
design description and technical drawings should therefore be requirements or regulations have to be considered as mini-
available to the inspector. The inspections to be carried out are mum requirements. If regulatory requirements prescribe that
distinguished as follows: the electrical installation in the structure must be regularly
tested, the effectiveness of the internal lightning protection
Inspection at the design stage measures should be checked during this test.
The inspection at the design stage should ensure that all as-
pects of the lightning protection system with its components Visual inspection
correspond to the state of the art in force at the design stage Lightning protection systems of structures and critical sections
and must be carried out before the service is provided.
of lightning protection systems (e.g. in case of considerable
Inspections during the construction phase influence from aggressive environmental conditions) must
Parts of the lightning protection system which will be no undergo a visual inspection between maintenance tests
longer accessible when the construction work is completed (Table 3.4.1.1).
must be inspected as long as this is possible. These include
foundation earth electrodes, earth-termination systems, rein- Additional inspection
forcement connections, concrete reinforcements used as room In addition to the maintenance tests, a lightning protection
shielding as well as down conductors and their connections system must be inspected if fundamental changes in use,
laid in concrete. The inspection comprises checking of techni- modification to the structure, restorations, extensions or repair
cal documents, on-site inspection and assessment of the work have been carried out on a protected structure. These inspec-
carried out (see Supplement 3 of the German DIN EN 62305-3 tions should also be carried out when it is known that light-
standard). ning has struck the lightning protection system.
Acceptance test
The acceptance test is carried out when the lightning protec- 3.4.2 Inspection measures
tion system has been completed. Compliance with the protec-
tion concept (design) conforming to the standard and the work The inspection comprises checking of technical documents, on-
performed (technical correctness taking into consideration the site inspection and measurements.
type of use, the technical equipment of the structure and the
site conditions) must be thoroughly inspected. Checking of technical documents
The technical documents must be checked to ensure they are
Maintenance test complete and comply with the standards.
Regular maintenance tests are the prerequisite for a perma-
nently effective lightning protection system. In Germany they On-site inspection
should be carried out every 1 to 4 years. Table 3.4.1.1 in- It must be checked whether:

Complete inspection
Visual inspection Complete Inspection
Class of LPS of critical situations a) b)
(year) (year)
(year)
I and II 1 2 1
III and IV 2 4 1
a) Lightning protection systems utilised in applications involving structures with a risk caused by explosive materials should be visually
inspected every 6 months. Electrical testing of the installation should be performed once a year. An acceptable exception to the yearly test
schedule would be to perform the tests on a 14 to 15 month cycle where it is considered beneficial to conduct earth resistance testing over
different times of the year to get an indication of seasonal variations.
b) Critical situations could include structures containing sensitive internal systems, office blocks, commercial buildings or places where a high
number of people may be present.
Table 3.4.1.1 Maximum period between inspections of an LPS according to Table E.2 of IEC 62305-3 (EN 62305-3)

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