Ludlum Measurements
Ludlum
Ludlum 9-4RF
Handheld survey meter
- Detector
- Air ionization chamber
- Weight with batteries
- 1.9 kg
10 referenced values
Bild: Ludlum
Ludlum 9-4
Handheld survey meter
Ludlum 9-4 – handheld survey meter from Ludlum Measurements.
- Chamber volume
- 220 cm³1
- Linearity
- ±10 %1
- Power supply
- 2 “D” batteries1
- Battery life and conditions
- 400 hours1
Download product sheet (PDF)All values with references – for tender documents
Specifications checked against the manufacturer’s documents on 2026-10-16
Overview
Specifications
The number after each value refers to the source listed below. Values are as published by the manufacturer; the exact configuration is always confirmed in our quotation.
Detector
| Chamber volume | 220 cm³1 |
|---|---|
| Window area | 40 cm²1 |
| Detector | Air ionization chamber (carbon-coated acrylic chamber)1 |
Performance
| Linearity | ±10 %1 |
|---|
Measuring range
| Response time | Approximately 5 s for 90% of final meter deflection on the x1 and x10 scales, and 3 s on the x100, x1k and x10k scales1 |
|---|---|
| Measurement range | 0 to 500 mSv/h (0 to 50,000 mR/hr)1 |
| Energy response | Within 20% of true value from 40 keV to 2 MeV1 |
| Range multipliers | ×1, ×10, ×100, ×1k, ×10k1 |
Mechanical
| Dimensions (H × W × L) | 23.4 x 8.9 x 21.6 cm including instrument handle1 |
|---|
Environment & ratings
| Operating temperature | -20 to 50 °C; temperature compensation maintains calibration within 15 % of the 25 °C reading1 |
|---|
General
| Meter dial | 0–5 mR/hr, BAT TEST1 |
|---|
The data comes from the manufacturer’s published documents. Manufacturers may change specifications; the current configuration and performance are confirmed in the quotation.
Documents
Sources
The number after each value refers to the source listed below. Values are as published by the manufacturer; the exact configuration is always confirmed in our quotation.
- 1
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