IEC 60704-2-9:2024

Overview

IEC 60704-2-9:2024 - Household and similar electrical appliances: Test code for the determination of airborne acoustical noise - Part 2-9: Particular requirements for electric hair care appliances.
This 2nd edition (2024) updates and replaces the 2003 edition and aligns this part with IEC 60704-1:2021. It applies to mains‑supplied hand‑held hairdryers and analogous fan‑driven hairstyling appliances (but excludes helmet‑type dryers and appliances with radiant heating). The standard defines how to measure and report noise emitted by these devices and provides specific test requirements to ensure comparable, repeatable acoustical noise data.

Key Topics

• Scope and exclusions: Applies to hand‑held hairdryers and fan‑driven hairstyling appliances; excludes helmet‑type dryers and radiant‑heating appliances.
• Reference framework: Intended to be used with IEC 60704-1:2021 (general test code). For declared noise emission values and verification see IEC 60704-3.
• Measurement methods: Direct and comparison methods allowed; ISO 3743‑1, ISO 3743‑2 and ISO 3744 can be used. Special precautions required if pure tones are present.
• Instrumentation: Microphone windscreens may be used; corrections for microphone sensitivity changes must be applied.
• Preconditioning and operation:
  • Equip appliances as for normal use (no attachments such as nozzles, diffusers, brushes).
  • Clean air intakes and filters.
  • Run‑in: at least 5 min at highest normal speed/temperature before measurements.
  • Stabilize: at least 2 min immediately before each measurement series.
  • Voltage tolerance: ±0.5 %.
  • Measurements taken at highest fan and heater settings for normal permanent use.
• Uncertainty and repeatability:
  • Standard deviations for sound power levels: repeatability σr = 0.4 dB, reproducibility σR = 0.8 dB.
  • For declaration/verification (per IEC 60704‑3): production σP 0.5 to 1.3 dB, total σt 0.9 to 1.5 dB, reference σM 1.5 dB.

Applications and Users

Who benefits from IEC 60704-2-9:

• Manufacturers of hand‑held hairdryers and fan‑driven hairstyling appliances for product development and quality control.
• Test laboratories performing sound pressure / sound power tests and reporting noise emission data.
• Regulatory bodies and compliance teams assessing product noise performance.
• Product designers aiming to reduce perceived noise and meet declared noise specifications.

Practical uses:

• Generate comparable noise data for datasheets and marketing claims (in conjunction with IEC 60704‑3).
• Support design decisions to lower airborne acoustical noise.
• Establish production and verification limits based on measurement uncertainty.

Related Standards

• IEC 60704-1:2021 - General requirements (use together)
• IEC 60704-3 - Declaration and verification of noise emission values
• ISO 3743-1, ISO 3743-2, ISO 3744 - Acoustic measurement methods

Keywords: IEC 60704-2-9, electric hair care appliances, hand-held hairdryers, airborne acoustical noise, noise measurement, sound power levels, measurement uncertainty, IEC 60704-1, IEC 60704-3.