HBK (Brüel & Kjær) · Personal Noise Dose Meter · Noise dosimeter
Brüel & Kjær 4448
DiscontinuedShoulder-worn personal noise dose meter with a body-mounted half-inch microphone, cable-free design and infrared data download to the Protector software. Measures A- and C-weighted exposure with 3 dB and 5 dB exchange rates; an intrinsically safe version (4448-B) was certified for ATEX zones. Not listed in HBK's current handheld range.
Specifications verified on .
- Type
- Noise dosimeter
- Channels
- 1
- Octave bands
- None
- Connectivity
- Infrared to USB (AO-1492 cable)
- Weight
- 71 g
- Battery life
- 28 h
Specifications
As published by HBK (Brüel & Kjær). Fields the manufacturer does not publish are omitted rather than estimated.
| Specification | Value |
|---|---|
| Standards | IEC 61252:2002, ANSI S1.25:1991 |
| Specification | Value |
|---|---|
| Channels | 1 |
| Measurement range | 65.0 to 140.3 dB (LAeq, LCeq) |
| Peak range | 95.0 to 143.3 dB (C-weighted peak) |
| Frequency weightings | A, C, Z |
| Time weightings | F, S, I |
| Simultaneous weightings | Yes |
| Parameters | LAeq, LCeq, LCeq-LAeq, Lav, LAIeq, LCpeak, LApeak, LZpeak, TWA, LAFmax, LASmax, LAImax, LAFmin, LAE, LEX,8h, Pa2h, % dose, projected dose, peak counter (135, 137, 140 dB) |
| Dosimetry | Yes |
| Exchange rates | 3 dB, 5 dB |
| Intrinsically safe marking | 4448-B: ATEX EEx ia I M1, EEx ia IIC T2 II 1 G (07ATEX2032X); FM/CSA Class 1 Div 1 Groups A-D T2 |
| Specification | Value |
|---|---|
| Octave bands | None |
| Reverberation time | No |
| Building acoustics | No |
| Audio recording | No |
| Specification | Value |
|---|---|
| Shortest logging interval | 1 min |
| Memory | 180 h of history, non-volatile |
| Specification | Value |
|---|---|
| Microphone | 1/2" condenser, body-mounted |
| Detachable preamplifier | No |
| Display | 100 x 32 pixel LCD, six languages |
| Battery | Internal rechargeable NiMH |
| Battery life | 28 h |
| Weight | 71 g |
| Dimensions (mm) | 80 x 47 x 52 including windscreen |
| Operating temperature (°C) | 0 to 40 |
| Specification | Value |
|---|---|
| Connectivity | Infrared to USB (AO-1492 cable) |
| Software | Protector Type 7825 |
Variants
| Variant | Difference |
|---|---|
| 4448-A | standard version |
| 4448-B (-002) | intrinsically safe version, ATEX certificate 07ATEX2032X |
Where this data comes from
| Kind | Document | Accessed |
|---|---|---|
| Datasheet | Product Data BP 2426-12, Personal Noise Dose Meter Type 4448 (2016-04, Spanish) | |
| Datasheet | Product Data BP 2388, Personal Noise Dose Meter Type 4448 |
Verified on . Only the manufacturer’s own published material is used; distributor pages are not sources.
Spec out of date? Tell us (reference hbk-4448).
Verified owner reviews
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Known issues and firmware notes
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Feature requests
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Read next
- How to choose a noise dosimeter · IEC 61252, exchange rates, criterion levels, badge vs cable, intrinsic safety, logging and audio.
- Sound level meter calibration and verification · Field calibration vs laboratory calibration, IEC 61672-3, ISO 17025, intervals, reading a certificate.
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