As a company or organization, you are legally required to maintain your property in a safe condition. When it comes to lightning protection, this is doubly true – a lightning protection system failure threatens not only property but, above all, lives. Let’s take a look at how often you must conduct lightning protection system inspections according to the applicable standard and what exactly the certified electrical inspector checks during an inspection.
What the standard says: ČSN EN 62305 and inspection intervals
The fundamental regulation for lightning protection is the set of standards ČSN EN 62305 (ed. 2), specifically Part 3, which deals with physical damage to structures and life hazard. This standard classifies structures into four Lightning Protection Levels (LPL) based on the degree of risk. The classification into an LPL class then determines how often you must conduct an inspection.
The periodic inspection intervals for an LPS (Lightning Protection System) are set as follows:
- Protection class LPL I and II (structures with high risk, e.g., chemical plants, hospitals, structures with an explosion hazard): complete inspection every 2 years
- Protection class LPL III and IV (standard commercial and administrative buildings, production halls without special risks, apartment buildings): complete inspection every 4 years
- Visual inspection (for all protection classes): every year
- Critical systems (structures where LPS failure would have fatal consequences): complete inspection and visual inspection every year
A visual inspection is a cursory check that can also be performed by a trained person from your company. In contrast, a complete inspection may only be performed by a certified electrical inspector with a valid certificate according to NV 194/2022 Sb., specifically with the E3A scope. This certificate is valid for 3 years – verify that the inspector you invite has their documentation in order.
If you are unsure which protection class your structure falls into, contact us – we will conduct an assessment and set up an optimal inspection schedule precisely according to the standard.
What is checked during a lightning protection system inspection
An LPS inspection is not just about whether a piece of wire is missing from the roof. It involves a comprehensive check of the entire system, which consists of three basic parts. Each has its specifics and potential defects.
Air-termination system
This is the part that captures the lightning strike – typically air-termination rods, conductors on the roof ridge, or a mesh system. During the inspection, we check:
- Mechanical damage, corrosion, or loose connections
- Correct anchoring to the building envelope
- Sufficient height and placement of air-termination rods relative to the protected parts of the structure
- Whether newly installed technologies (HVAC, antennas, PV system panels) encroach upon the protective zone of the air-termination system
Additional installations on roofs are a frequent problem. A company has a photovoltaic system or air conditioning installed but fails to address whether these elements protrude outside the protected zone and require their own air-termination protection.
Down conductors
Down conductors carry the lightning current from the air-termination system to the earthing system. We check:
- The integrity and soundness of all down conductors (an interrupted down conductor = non-functional protection)
- The tightness of joints and clamps, including measured joints in test clamps
- Maintaining a sufficient separation distance from combustible parts of the building
- Visible marking and protection against mechanical damage at ground level
In production halls and warehouses, down conductors are often damaged by material handling or forklifts. The annual visual inspection should detect this damage in time.
Earthing and surge protection
This is the part you cannot check with the naked eye. It requires measurement with instruments:
- Earth resistance measurement – must correspond to the values required by the standard for the given protection class. High resistance means the lightning current has nowhere to safely dissipate.
- Surge protective device (SPD) check – both visually and by measurement. SPDs protect the internal electrical installation and appliances from overvoltage, which can also occur from a lightning strike into the network outside the building. A faulty or missing surge protective device is a fundamental risk in company buildings with sensitive electronics.
Why this should not be underestimated in company buildings
In production halls, warehouses, or administrative buildings, the assumption is often that “lightning won’t strike there anyway.” However, damage does not only occur from a direct strike. Overvoltage in the network after a nearby lightning strike can reliably destroy a server room, a production line, or a security system. A non-functional lightning protection system then means the insurance company may reduce or completely deny the insurance claim.
Another risk is the liability of the statutory representative. If injury or death occurs as a result of a neglected inspection, the managing director or company owner bears responsibility. Sanctions under Act No. 251/2005 Sb., on labour inspection, can reach up to CZK 2,000,000 for legal entities and self-employed persons.
Furthermore, a lightning protection system inspection is closely related to the overall condition of the electrical installation in the building. During a periodic inspection, we often uncover problems that fall under electrical installation inspection – from outdated switchboards to missing residual current devices (RCDs). It therefore makes sense to address both inspections simultaneously with a single supplier.
How to proceed when an inspection fails
You will receive an inspection report from the inspection listing the defects. Each defect is assigned a classification according to severity. Minor defects (e.g., missing labels) do not prevent operation but must be rectified by the next inspection. Major defects (e.g., interrupted down conductor, high earth resistance) mean the system is not fulfilling its function – immediate rectification is required here.
Rectifying defects does not necessarily mean a complete reconstruction. It often involves partial repairs, replacement of corroded parts, or addition of surge protective devices. After the repair, we perform a follow-up inspection to confirm everything is in order.
What a lightning protection system inspection roughly costs
The price depends on the size of the building, the number of down conductors, and test clamps. For a smaller administrative building or shop, the price ranges approximately from CZK 1,000 to CZK 3,000. For extensive production sites with multiple buildings and a complex air-termination system, the price is higher – it always depends on the specific scope of work. We will prepare a precise price quote for you after a non-binding inquiry and clarification of the building parameters.
Frequently asked questions: lightning protection inspection
How often must lightning protection inspections be carried out? According to ČSN EN 62305 ed. 2, a complete inspection of the LPS is carried out based on the lightning protection level: for LPL I and II (buildings with high risk) every 2 years, for LPL III and IV (common commercial and administrative buildings) every 4 years. A visual inspection is recommended every year.
Who is authorised to perform a lightning protection inspection? A complete inspection may only be performed by an inspection technician with a valid certificate according to NV č. 194/2022 Sb. in the scope of E3A. A visual inspection can be carried out by a trained person from your company.
What are the consequences of a missing lightning protection inspection? Operating a designated technical device without a valid inspection within the specified period is a condition endangering safety. In the event of damage, the insurance company may complicate the settlement, and the labour inspectorate may impose a fine according to Act No. 251/2005 Sb. of up to CZK 2,000,000.
Are you certain your lightning protection system would pass an inspection without defects? If you don’t know, or if the deadline for a periodic inspection is approaching, contact us. We will arrange a complete LPS inspection, including measurements and the issuance of statutory documentation. Write to info@sohe.cz or call +420 724 689 762. We will be happy to do the job for you as if we were doing it for ourselves.