Noise Dosimeter vs Sound Level Meter

Buy the Extech SL400 noise dosimeter when the microphone must follow a person and the deliverable is personal dose or TWA; buy the REED R8080 sound level meter for a timestamped history at a location. The SL400 also has a sound-level mode, but its PC compatibility needs checking before purchase; the R8080 has explicitly documented Windows downloads and Excel export. These picks follow the SL400 manual and REED specifications.

Quick picks: choose the record you need

• Personal exposure: Extech SL400. Our pick for a moving worker's survey: belt clip, clip-on microphone, dose and TWA functions.
• Location history: REED R8080. Our pick for a saved sound-level timeline: tripod mount, internal timestamps and USB downloads.

OSHA's measurement guidance describes dosimetry as personal sampling averaged over time, while sound level meters help identify individual noise sources. A logger left beside a machine answers a different question from a microphone following someone between tasks. Choose the required record before comparing memory counts.

SL400 vs R8080: the comparison table

These are manufacturer specifications, not independently verified performance.

Sources: SL400 manual, SL400 datasheet, R8080 page and R8080 manual. The SL400 memory figures describe different operating modes; the larger sound-level allowance is not its dose-recording capacity.

Best for personal exposure: Extech SL400

Choose the SL400 for its documented exposure functions and wearable microphone arrangement. The standard package includes the belt clip, microphone and cable, windscreen, 9V battery, software, USB cable and carrying case, according to its datasheet. The manual identifies the supplied connection as Mini USB, Mini B.

For working-day planning, the manual specifies 24-hour battery life with a 9V alkaline battery. Treat that as a maker specification and check battery condition before the survey. OSHA places a personal dosimeter microphone in the hearing zone, such as the shoulder or lapel near the ear; clothing contact and rubbing can affect results. Check that the supplied cable and clip suit the wearer's clothing and tasks.

Range-label conflict: the manual calls 70–140 dB the high sound-level range; the datasheet places 70–140 dB under C/Z peak wording. The manual also separates display ranges from its primary RMS ranges at the reference frequency. Get Extech to confirm the usable range for your required metric if the upper endpoint determines the purchase; do not treat a display limit as an unrestricted measurement specification.

The bigger practical restriction is data retrieval: the manual says memory can only be downloaded and erased through software. A readable display alone does not complete the recording kit.

See the SL400 package at Extech

Best for location logging: REED R8080

The R8080 suits a repeatable observation point: REED documents a tripod mount, 64,000 timestamped datapoints, and a 1–60-second recording interval. That recording interval is separate from its Fast/Slow time weighting. Its standard package contains the windscreen, USB cable, PC software, hard case and batteries. The manual specifies four AAA batteries and disables automatic shut-off during logging or a PC connection.

Keep the output distinction clear. REED advertises CAL Leq in PC software, and the software guide describes LEQ over a specified period. These documents do not establish standalone integrating LAeq performance or a personal-dose calculation. For a whole-session personal exposure result, our pick remains the SL400.

If you only need display readings, use our REED R8050 vs R8080 guide. For the wider shortlist, return to best sound level meters.

See the R8080 package at REED

Buying guide: assemble a usable recording kit

Specify the metric and protocol

Ask whoever will receive the record to specify the metric, sampling period and settings. The SL400 manual documents dose, TWA, Leq, sound exposure level and peak functions; those names describe different outputs. Its Leq definition refers to the equivalent continuous level over the measurement duration. A maximum reading alone does not supply a personal-dose result.

Settings matter as much as the model. In its inspector guidance, OSHA specifies A weighting, Slow response, a 5 dB exchange rate and 90 dBA criterion level; the sampling threshold is 80 dBA for Action Level measurements and 90 dBA for PEL measurements. That is a distinction within OSHA's procedure, not a universal configuration for every noise survey.

Extech documents adjustable criterion, threshold and exchange rate, but its datasheet promises one user-defined measurement setup. Do not assume it records several independent exposure protocols simultaneously. Check the required settings rather than relying on a preset's name.

Decode the package suffix before ordering

Package sources: SL400 datasheet, R8080, R8080-KIT and R8080-KIT2. Match the contents to the exact suffix.

Match the calibrator, microphone and adapter

For the SL400's 94.0 dB, 1000 Hz procedure, our accessory choice is the Extech 407744: its documented output is 94 dB at 1 kHz, matching the required level and frequency. Its manual says the half-inch microphone adapter is supplied attached, matching the SL400's half-inch microphone. Keep that adapter with the calibrator. The related 407766 adds a 114 dB output; that extra setting is unnecessary for the SL400 procedure described here.

For the R8080, use the REED R8090 named in its manual, or the R8080-KIT containing it. REED documents a half-inch microphone opening and 94/114 dB at 1000 Hz; use the 94 dB setting for the R8080 procedure. See our sound-level-meter calibrator compatibility guide for the broader fit decision.

OSHA distinguishes periodic calibration from pre- and post-use checks. Its procedure calls for documenting both field checks and performing the post-use check without adjustment. Budget for the correct source and calibration documentation as part of the kit.

Prove the computer handoff before the real session

SL400: the datasheet names Windows 7 and 8. The manual instead directs buyers to check the latest software compatibility, run ExtechInstaller.exe, and use the application's Help instructions. These saved documents do not establish Windows 11 support or a specific measurement-export file format. Confirm both with Extech before ordering when either is essential; do not confuse the manual's setup-file import/export reference with exported measurement results.

R8080: the product page and download page list Windows XP/Vista/7/8/10/11. The shorter software guide lists support only through Windows 10, a documentation difference worth checking for your installed version. That guide explicitly documents graphs and Excel export.

• Yes: R8080: Windows downloads and Excel export are explicitly documented.
• Partly: SL400: confirm the current host support and required measurement-export format.
• No: Native macOS support is not established by these documents for either recorder.

Run a short rehearsal and open the saved result before relying on the kit. For SL400, the manual documents starting a measurement and enabling automatic data recording separately; check that recording is actually enabled. Retain the original downloaded data alongside the report you hand over.

How we choose

We compared official manuals, datasheets, kit lists and software documentation, using OSHA's measurement guidance to distinguish personal exposure from location measurements. Recommendations are based on documented functions and compatibility; we have not physically tested these instruments. Unresolved specifications remain identified. Read our selection method.

Following OSHA's guidance, plan the microphone position, record activities and check calibration before and after use; a downloaded graph does not replace session notes.

1. 1

   Before the session

   Agree the metric and settings; check batteries, microphone placement and calibration.

2. 2

   During the session

   Verify recording and keep notes on tasks, locations and pauses.

3. 3

   After the session

   Document the calibration check, download the record and retain the session notes with it.

Verdict

Choose SL400 plus a suitable calibration source for personal exposure recording, provided the supported computer and report workflow meet the job. Choose R8080 for location history, the R8080-KIT when you need its R8090 calibrator, or KIT2 when the missing accessory is a tripod. Buy the complete path from microphone placement to a usable saved record.