Ludlum 26-1

Handheld contamination meter

Ludlum 26-1 – handheld contamination meter from Ludlum Measurements. Detector: Pancake GM. Enclosure rating and conditions: IP53.

Detector: Pancake GM1
Enclosure rating and conditions: IP531
Weight as specified: 0.45 kg1

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

Key features

Detector: Pancake GM
Linearity: ±10%
Power: Two “AA” batteries

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	Pancake GM1
Window area	Active: 15.51 cm²; open: 12.26 cm²2

Performance

Linearity	±10%1
Resolution time	Approximately 110 µs as defined by IEC 603251

Measuring range

Response time	User-selectable from 1 to 60 seconds, or auto-response rate FAST or SLOW1

Connectivity & interface

Display range	0.00 cps–19.9 kcps; 0.00 cpm–999 kcpm; 0.00 Bq–19.9 kBq; 0.00 dpm–999 kdpm; 0.00–500 mR/h; 0.000–1999 µSv/h1

Power & battery

Power supply	Two “AA” batteries1
Battery life and conditions	Approximately 1000 hours of operation (as low as 500 hours with backlight configured for 'Continuous On')2

Mechanical

Dimensions (H × W × L)	4.6 x 6.9 x 27.2 cm1
Weight as specified	0.45 kg1

Environment & ratings

Operating temperature	-20 to 50 °C1
Enclosure rating and conditions	IP531

Ordering & accessories

Part number	48-39651

General

Dose filter	Optional1

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 26-1 & 26-1DOSE – Integrated Frisker (data sheet, 0426)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 26-1 Series – Integrated Frisker
Publisher: Ludlum MeasurementsProduct page Specifications tab, 'Detector'; Specifications tab, 'Linearity'; Specifications tab, 'Power'; Specifications tab, 'Temperature Range' … Checked 2026-10-16
2
Model 26-1 & 26-1DOSE – Integrated Frisker (data sheet, 0426)
Publisher: Ludlum MeasurementsDatasheet p. 2, Specifications, 'Battery Life'; p. 2, Specifications, 'Window Area' Checked 2026-10-16