Ludlum 2401-EC2A

Handheld survey meter

Ludlum 2401-EC2A – handheld survey meter from Ludlum Measurements. Detector: Energy-compensated GM tube (integrated). Measurement range as specified: 0 to 20 mSv/h (0 to 2 R/hr).

Detector: Energy-compensated GM tube (integrated)1
Measurement range as specified: 0 to 20 mSv/h (0 to 2 R/hr)1
Weight as specified: 0.4 kg including battery1

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 Emergency services & first response Environmental monitoring & radiation protection Industry & quality control

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	Energy-compensated GM tube (integrated)1

Measuring range

Measurement range as specified	0 to 20 mSv/h (0 to 2 R/hr)1
Sensitivity (¹³⁷Cs gamma)	Typically 100 cpm per mR/hr1
Response time	Typically 11 s from 10 % to 90 % of final reading1
Energy response	Reading within 20% of true value1

Power & battery

Power supply	9 V battery1
Battery life and conditions	Typically 250 hours with alkaline battery at normal background levels1

Mechanical

Dimensions (H × W × L)	4.6 x 8.4 x 13.5 cm1
Weight as specified	0.4 kg including battery1

Environment & ratings

Operating temperature	−20 to +50 °C (−4 to 122 °F); may be certified for operation from −40 to +65 °C (−40 to 150 °F)2

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

Documents

PDFDatablad (PDF)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 2401-EC2A Pocket-Size Survey Meter with Alarm
Publisher: Ludlum MeasurementsProduct page Specifications tab, 'Detector'; Features; Specifications tab, 'Range'; Specifications tab, 'Sensitivity (137Cs gamma)'; Specifications tab, 'Power' … Checked 2026-10-16
2
Ludlum Models 2401-ECA, 2401-EWA, 2401-EC2A and 2401-PA manual
Publisher: Ludlum MeasurementsManual Manual p. 15 (p. 5-1), section 5, Environmental Conditions for Normal Use Checked 2026-10-16