EN 117 Wood Preservatives - Determination of Toxicity Values ​​Against Reticulitermes Species (European Termites)

The European standard “EN 117 Wood preservatives - Determination of toxicity values ​​against Reticulitermes species (European termites) (laboratory method)” describes a method for determining the toxicity values ​​of a wood preservative against Reticulitermes species of European termites.

This method can be applied not only to different Reticulitermes species, but also to other species of the Rhinotermitidae family. If necessary, temperature and humidity conditions should be adapted to the specific requirements of the species in question.

The method described applies to the following:

• Water-insoluble chemicals studied as active insecticides
• Organic water-dispersible formulations prepared as supplied or by diluting concentrates in the laboratory.
• Water-soluble substances, such as salts.

This method can be used in conjunction with an aging procedure, such as those conforming to EN 73 or EN 84 standards.

Reticulitermes is a genus of termites in the family Heterotermitidae. They are found in most temperate regions of the world, including much of Asia, Western Europe, and all of North America.

The described test method is based on the following principles:

• Impregnating various test samples of sensitive wood with a series of solutions in which the concentration of the preservative changes in a specific progression.
• Test specimens are exposed to specific Reticulitermes colonies, and the attack is evaluated under constant conditions and for a fixed period of time. In the biological verification of individual species, it is essential to specify the place of origin of each test termite species. The description of the place of origin should include at least the name of the region.
• Comparison of these results with those obtained from untreated and control test samples treated with solvent or diluent.
• Deriving the toxicity values ​​of the tested product.

In short, EN 117 is a European standard that defines a laboratory method for determining the effectiveness of wood preservatives against Reticulitermes species, also known as European termites. This standard provides a consistent methodology for evaluating whether a wood preservative can protect wood from termite attack under controlled laboratory conditions. It is widely used across Europe by wood preservative manufacturers, testing laboratories, certification bodies, and regulatory authorities.

Termites are among the most destructive biological agents affecting wood. By consuming the cellulose in wood, they can rapidly weaken structural lumber, power poles, railway sleepers, fences, and other wooden products.

The main objectives of the EN 117 standard are as follows:

• To determine the toxic efficacy of wood preservatives against European termites.
• Comparing the performance of different preservative formulations.
• To support product development and quality control.
• To create standardized data for certification and regulatory approval.
• To increase the long-term durability of wood used in termite-prone environments.

The described test method is applicable to the following:

• Water-insoluble chemicals used as active insecticides.
• Organic, water-dispersible preservative formulations.
• Water-soluble preservatives, such as inorganic salts.

This standard also specifies that testing can be combined with artificial aging procedures, such as those described in EN 73 or EN 84 standards, to assess protective performance against weathering or leakage.

In principle, this test evaluates whether termites damage wood treated with a preservative. Small wood samples are impregnated with various concentrations of the preservative and then exposed to colonies of live termites under carefully controlled environmental conditions. After the exposure time, the laboratory evaluates the following:

• Termite mortality rate
• The degree of damage to the wood.
• Visual damage to samples
• Weight loss of wood
• Minimum preservative concentration required for preservation.

These measurements help determine the toxicity of the preservative to termites.

Typical materials used in the tests include:

• Standardized wood samples
• Reticulitermes termite colonies grown in a laboratory environment.
• Preservative solutions at different concentrations.
• Controlled environmental chambers
• Moisture-retaining substrates
• Precision weighing equipment
• Damage assessment tools

Careful sample preparation ensures reproducible results across laboratories.

In general, this testing process follows these steps:

• Preparation of flawless wood samples.
• Samples are processed with known concentrations of preservatives.
• Conditioning of processed samples.
• Placement of active termite groups into test containers.
• Maintaining controlled temperature and humidity throughout the exposure period.
• Monitoring termite activity.
• Assessment of termite mortality rate and wood damage after testing.
• Calculation of toxic threshold and protective efficacy.

The following performance indicators are considered during the tests:

• Termite mortality rate
• Severity of nutritional damage
• Weight loss of processed wood.
• Visual condition of the samples
• Efficiency compared to untreated control samples.
• Lowest effective preservative concentration

Taken together, this data shows how well the protector protects the wood against termite attack.

The EN 117 standard plays a significant role in the wood preservation industry because:

• It provides harmonized laboratory testing across Europe.
• It provides an objective comparison between protective systems.
• It supports certification and regulatory compliance.
• It helps manufacturers optimize their preservative formulations.
• It reduces premature failure of wooden structures.
• It increases confidence in processed wood products.

Without standardized tests, it is not easy to compare preservative performance between manufacturers or laboratories.

The EN 117 standard applies to many sectors, including:

• Wood preservative production
• Wood processing plants
• Construction
• Electricity pole manufacturing
• Railway infrastructure
• Agricultural fences
• Outdoor landscaping
• Marine timber applications
• Forestry
• Construction materials certification laboratories

Organizations can take advantage of the EN 117 standard as follows:

• It produces reproducible laboratory results.
• It supports product innovation.
• It increases product reliability.
• It facilitates market adoption across Europe.
• It helps meet legal requirements.
• It reduces warranty claims resulting from termite damage.
• It increases customer confidence in processed wood products.

The EN 117 standard is frequently used in conjunction with other wood durability standards, including:

• EN 73 Accelerated aging of wood treated by evaporation.
• EN 84 Accelerated aging via leakage.
• EN 599 Performance requirements for wood preservatives.
• EN 335 Use classes defining biological exposure risks.
• EN 351 Preservative-treated solid wood specifications

Together, these standards provide a comprehensive framework for evaluating the performance and durability of engineered lumber.

In conclusion, the EN 117 standard provides a consistent and scientifically validated testing method, enabling manufacturers and laboratories to evaluate preservative efficacy, objectively compare products, and demonstrate compliance with European performance requirements. This standard significantly contributes to the production of durable, reliable, and safe wood products for use in termite-exposed environments, while supporting quality assurance across the wood preservation industry.

For many years, our organization, with its competent and experienced staff, has been understanding the needs of its clients, providing the advanced testing services they require, and assisting them in the establishment, implementation, and improvement of management systems. Within this framework, we also provide testing services in accordance with the EN 117 standard.