IEC 60695-5-1:2021

Overview

IEC 60695-5-1:2021 is a core International Electrotechnical Commission (IEC) standard that provides general guidance on the evaluation and measurement of corrosion damage effects induced by fire effluent. This standard is a critical reference for technical committees engaged in developing fire safety standards for electrotechnical products. The guidance encompasses:

• General aspects of corrosion damage test methods
• Methods for measuring corrosion damage
• Consideration and selection of appropriate test methods
• Relevance of corrosion data to fire hazard assessment

As a basic safety publication, IEC 60695-5-1 is intended for the harmonized development of standards by technical committees, ensuring a consistent approach to fire hazard assessment across the electrical and electronic industries.

Key Topics

Corrosion Damage Scenarios

IEC 60695-5-1 identifies three primary scenarios for corrosion risk:

• Corrosion within electrotechnical equipment following internal heat or ignition
• Corrosion from external sources affecting electrotechnical systems
• Corrosion of building structures resulting from effluent released by electrotechnical equipment

Types of Corrosion Damage

The standard outlines four main effects:

• Metal loss: Oxidation or reaction of metal surfaces, potentially decreasing conductivity or causing structure failure
• Immobility of moving parts: Deposits or corrosion products make mechanical or electromechanical parts seize
• Bridging of conductor circuits: Conductive particulates or corrosion products lead to undesired leakage currents, a concern for sensitive electronic equipment
• Non-conducting layers: Insulating corrosion layers at contact surfaces cause disruption of electrical circuits

Factors Influencing Corrosivity

The extent and nature of fire effluent-induced corrosion are shaped by:

• Chemical composition and physical properties of the fire effluent
• Fire development stage and material combusted
• Environmental conditions, especially temperature and humidity
• Duration of exposure and the presence of energized circuits
• Post-fire cleaning practices

Fire Scenarios and Modeling

IEC 60695-5-1 discusses how compartment fire development stages - from smouldering (non-flaming) to fully-developed fire and decay - influence the corrosivity of fire effluents. Accurate hazard assessment depends on realistic fire modeling and representation in laboratory-scale tests.

Applications

IEC 60695-5-1:2021 is a key document for those involved in:

• Standards Development: Technical committees use this guidance during the creation of safety standards for electrical and electronic products, aiming for global harmonization and improved fire hazard assessment.
• Hazard Assessment: Enables a science-based approach to judge the risk of fire effluent-induced corrosion damage in various scenarios.
• Product Safety Strategy: Informs decisions on material selection, construction, and protective measures within the design process of high-value or safety-critical electrotechnical equipment.
• Fire Safety Engineering: Provides essential input for modeling fire impacts on system performance, particularly where corrosion could disrupt electrical functions or compromise structural safety.

Related Standards

Several publications work alongside IEC 60695-5-1:

• IEC TS 60695-5-2: Summary and relevance of corrosion damage test methods
• IEC 60695-1-10: Guidance for assessing the fire hazard of electrotechnical products - General guidelines
• IEC 60695-1-11: Fire hazard assessment concepts for electrotechnical products
• ISO 11907-1:2019: Corrosivity of fire effluents in plastics - General concepts
• ISO 13943:2017: Fire safety - Vocabulary
• ISO/IEC Guide 51: Guidelines for inclusion of safety aspects in standards
• ISO 19706: Guidelines for assessing fire threat to people

Practical Value

Adoption of IEC 60695-5-1:2021 supports uniform, reliable fire hazard testing, especially concerning corrosion damage from fire effluent. By guiding the measurement and assessment of corrosive effects, it ensures the performance and safety integrity of electrotechnical products in fire scenarios, ultimately helping to safeguard people, property, and critical infrastructure.