The IEC 60118-7 standard changed dramatically in 2005. The new version is almost identical to the ANSI S3.22-2003 standard (the telecoil tests remain different). The following table contains the major changes from IEC 94 to IEC 05.
|
Description |
IEC 94 |
IEC 05 |
| Reference frequency | Single frequency: 1600 Hz or 2500 Hz | High frequency average (HFA) of 1000, 1600, and 2500 Hz (or special purpose average, as specified) |
| Full-on Gain | Measured at 60 dB SPL for most hearing aids, or 50 dB SPL for high gain hearing aids | Measured at 50 dB SPL for all hearing aids |
| Reference Test Gain (RTG) | Either OSPL90 at ref freq minus 75 or Full-on gain at ref freq minus 7 dB | HFA-OSPL90 – 77 |
| Harmonic distortion | Measured at 70 dB at 1/3 octave frequency specified by the manufacturer between 400 and 1600 Hz | Measured at 500 Hz @ 70 dB SPL, 800 Hz @ 70 dB SPL, 1600 Hz @ 65 dB SPL |
| Equivalent Input Noise | Measured with no input Subtract RTG from result. | Measured with no input. Subtract HFA Gain obtained with a 50 dB SPL input. |
| Battery current | Measured at 60 dB SPL input at reference frequency | Measured at 65 dB at 1000 Hz |
| Telecoil | Measured at 10 mA/m at full-on gain. | Measured at 31.6 mA/m at RTG. A second result measured at 10 mA/m at full-on gain |
| I/O | Not required | AGC aids tested at 2000 Hz plus optional 250, 500, 1000, and 4000 Hz frequencies |
| Attack/release | Not required | AGC aids tested at 2000 Hz plus optional 250, 500, 1000, and 4000 Hz frequencies |