ISO 4892-4:2024

Overview

ISO 4892-4:2024 - Plastics - Methods of exposure to laboratory light sources - Part 4: Open‑flame carbon‑arc lamps specifies laboratory methods to reproduce outdoor weathering of plastics using filtered open‑flame carbon‑arc light in the presence of moisture. The standard defines how to expose specimens under controlled temperature, moisture/humidity, and spectral irradiance conditions to simulate global solar radiation or window‑glass filtered solar radiation for accelerated weathering and comparative testing.

Key topics and requirements

• Purpose: Reproduce weathering effects (UV, visible, heat, moisture) that occur in end‑use environments using open‑flame carbon‑arc lamps.
• Laboratory light source: Requirements for open‑flame carbon‑arc apparatus, including carbon rods (rare‑earth salts/coatings) and the use of glass filters.
• Filter types: Descriptions of daylight filters (type 1), window‑glass filters (type 2) and extended‑UV filters (type 3) to tailor spectral irradiance to target solar conditions.
• Spectral irradiance measurement: Spectral output is measured (typically 250–400 nm in 2 nm increments) and reported as passband percentages (e.g., 290–320 nm, 320–360 nm, 360–400 nm) relative to total UV irradiance.
• Environmental control: Controlled black‑panel/black‑standard temperature, chamber air temperature, relative humidity, and programmed spray or condensation cycles to simulate moisture exposure.
• Apparatus and instrumentation: Test chamber, radiometer, thermometer, spray system, specimen holders and equipment to assess property changes.
• Procedure and reporting: Specimen mounting, exposure cycles (light/dark), radiant exposure measurement, and post‑exposure evaluation (changes in color, mechanical or physical properties). A reference control material is recommended; intercomparisons between devices require established statistical relationships.

Applications and users

ISO 4892-4:2024 is used for:

• Accelerated weathering testing of plastics, coatings and polymeric components.
• Predicting durability and service life where UV and moisture are key degradation factors.
• Comparative product development, quality control, failure analysis and regulatory compliance.

Primary users:

• Materials scientists, polymer formulators and R&D laboratories
• Test houses and quality assurance teams
• Manufacturers of plastics, outdoor equipment, automotive glazing and architectural materials
• Certification bodies and standards organizations

Related standards

• ISO 4892-1 - General guidance and requirements for laboratory light‑source exposure methods.
• ISO 4582 - Determination of changes in colour and property variation after exposure to solar or laboratory sources.

Keywords: ISO 4892-4:2024, plastics weathering, open‑flame carbon‑arc, laboratory light sources, accelerated weathering, spectral irradiance, daylight filters, window‑glass filters, moisture exposure, black‑panel temperature.