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Model 25-IS Series

Intrinsically Safe Personal Radiation Monitor

Model 25-IS Part Number: 48-3661
Model 25-IS-1 Part Number: 48-3686

Features

Intrinsically Safe Certification
Dose Rate Range:
- Model 25-IS: 0.01 mR/hr to 999 R/hr
- Model 25-IS-1: 0.001 mSv/h to 9.99 Sv/h
Accumulated Dose Range
- Model 25-IS: 0 to 999 R
- Model 25-IS-1: 0 to 999 Sv
Lightweight
Rugged, Shockproof Construction
Water Resistant Design
Easy to Use
6000 Hour Battery Life
Audible and Visual Alerts and Alarms
Backlit LCD Display

The Model 25-IS and Model 25-IS-1 are intrinsically safe versions of the Model 25 Series Personal Radiation Monitors. They are small, rugged devices designed to warn emergency response personnel of any dangerous radiation fields that they may encounter, and are certified for use in areas where explosion safety is a concern. These easy-to-use instruments incorporate a GM detector capable of measuring radiation fields up to 9.99 Sv/h (999 R/hr).

The Model 25-IS Series backlit LCD readout displays dose rate, accumulated dose, and time remaining to the dose limit. Visual and audible alarms can be set over the entire measurement range. No special equipment is required to either calibrate or set up operational parameters.

The units can be worn on a belt, a lanyard, or an armband. A lanyard and a rubber boot with a built-in feed through are included with each instrument. See the Options tab below for other available accessories.

NOTE: Model 25-IS Series instruments are not intended to measure background levels of radiation.

Specifications

Detector	Internal energy-compensated GM
Energy Range	60 keV to 2 MeV
Display	3½ digit backlit LCD display
Display Range	Model 25-IS: 0.01 mR/hr (mR) to 999 R/hr (R) Model 25-IS-1: 0.001 mSv/h (mSv) to 9.99 Sv/h (Sv) Also displays time remaining from 19:59 to 00:01 (in hh:mm format)
Gamma Response	Model 25-IS: Typically 18 cpm per mR/hr Model 25-IS-1: Typically 1800 cpm per mSv/hr
Alerts & Alarms	Radiation alarms are adjustable over entire range. There are distinct alerts and alarms for exposure and accumulated dose: Dose rate alert Dose rate (hi) Accumulated dose alert Accumulated dose (hi) Time remaining to allowed dose (hi) Detector failure alert Low-battery notice when only 8 hours remain
Loss of Count Protection	If no pulses are received from the detector in 60 minutes, instrument failure is indicated by an audible and visual alarm and the display alternating between "0.0" and "F"
Audio	Built-in speaker (typically 95 dB at 30.5 cm [1 ft])
Calibration	Requires no tools or software when exposed to a traceable radiation field
Calibrated Range	Normally calibrated from: Model 25-IS: 2 mR/hr to 999 R/hr Model 25-IS-1: 0.02 mSv/h to 9.99 Sv/h
Temperature Range	-40 to 65 °C (-40 to 150 °F)
Power	2 each lithium coin cell batteries (see Warning note below)
Battery Life	Typically 6000 hours. Provides 8 hours warning of low battery.
Construction	Injection-molded plastic housing with sub-surface printed membrane front panel, completely gasketed for water resistance
Size (H x W x L)	7.6 x 5.4 x 1.7 cm (3.0 x 2.1 x 0.69 in.)
Weight	144 g (5.1 oz), including batteries
Intrinsically Safe Certification	Class I, Division 1, Groups A-D, Class II, III, Division 1, Groups E, F, and G, T6 UL 61010-1/CSA C22.2 No. 61010-1: Standard for Safety Electrical Equipment for Measurement, Control, and Laboratory Use; Part 1: General Requirements UL 913: Standard for Safety Intrinsically Safe Apparatus and Associated Apparatus for Use in Class I, II, and III, Division I, Hazardous (Classified) Locations CSA C22.2 No. 157: Intrinsically Safe and Non-Incendive Equipment for Use in Hazardous Locations

WARNING: Use only DL2450 (NEDA / ANSI / IEC / #5029LC) coin cell batteries. To reduce the risk of ignition of a flammable or explosive atmosphere, batteries must be changed only in a location known to be a non-hazardous area.

WARNING: When repairing this unit, substitution of components may impair intrinsic safety.

Options

Option	Description	Part Number
Model 25-Series Arm Band	Adjustable strap with a hook and loop closure.	21-8974
Model 25-Series Nylon Case	Black nylon case with a clear window for viewing the instrument display. Includes belt clip.	2311485