Ludlum 30-7B

Portable neutron meter

Ludlum 30-7B – portable neutron meter from Ludlum Measurements. Detector: ³He proportional detector. Measurement range: 0 to 99.9 mSv/h (0 to 9.99 rem/hr).

Detector: ³He proportional detector1
Measurement range: 0 to 99.9 mSv/h (0 to 9.99 rem/hr)2
Weight as specified: Display Unit: 174 g Detector: 4.6 kg2

Download product sheet (PDF)All values with references – for tender documents

Specifications checked against the manufacturer’s documents on 2026-10-16

Manufacturer’s product page (opens in a new tab)

Overview

Nuclear power & nuclear technology Defence, security & preparedness Research & laboratories

Key features

Detector: ³He proportional detector
Measurement range: 0 to 99.9 mSv/h (0 to 9.99 rem/hr)
Linearity: ±10 %

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

Detector	³He proportional detector1

Performance

Linearity	±10 %2

Measuring range

Measurement range	0 to 99.9 mSv/h (0 to 9.99 rem/hr)2
Response time	User-selectable from 1 to 60 seconds, Auto-Response Rate FAST or SLOW, or Fixed FAST and SLOW2
Neutron sensitivity (bare AmBe)	Typically 4.5 cpm per µSv/h (45 cpm per mrem/hr)2

Power & battery

Power supply	Two alkaline or two rechargeable “AAA” batteries2
Battery life and conditions	Approximately 100 hours of operation2

Mechanical

Dimensions as specified	Display unit: 8.5 × 8.0 × 4.8 cm (H × W × L); detector: 19.5 cm diameter REM ball with ³He detector (1.6 × 2.5 cm, D × L)1
Weight as specified	Display Unit: 174 g Detector: 4.6 kg2

Environment & ratings

Operating temperature	-20 to 50 °C2
Enclosure rating and conditions	IP52 with audio-hole seal option2

Ordering & accessories

Part number	48-43092

The data comes from the manufacturer’s published documents. Manufacturers may change specifications; the current configuration and performance are confirmed in the quotation.

Documents

PDFModel 30-7 Series – Lightweight Digital Neutron Detector (data sheet, Apr 2024)Datasheet · Ludlum

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
Model 30-7 Series – Lightweight Digital Neutron Detector (data sheet, Apr 2024)
Publisher: Ludlum MeasurementsDatasheet Specifications, 'Detector'; Specifications, 'Size' Checked 2026-10-16
2
Model 30-7 Series – Lightweight Digital Neutron Survey Meter
Publisher: Ludlum MeasurementsProduct page Specifications tab, 'Measurement Range'; Specifications tab, 'Linearity'; Specifications tab, 'Power'; Specifications tab, 'Battery Life' … Checked 2026-10-16