Honeywell · Modular multi-gas detector

Honeywell Flex 5 Series

Name: Honeywell Flex 5 Series Modular Multi-Gas Detector
Brand: Honeywell

Your Fleet. Your Way. Designed to Be Ready

A modular, portable multi-gas detection platform that monitors up to six gases simultaneously. Swappable sensor cartridges let the same base unit serve as a pumped device for sampling in confined spaces or as a wearable for personal protection, with connectivity on your terms and NFC actionTAGS that take steps out of the pre-entry routine.

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Download datasheet (PDF)

6Up to six gases, depending on configuration

3Fundamental configurations, diffusion or pumped

IP68IP66 & IP68 diffusion, IP65 pumped

12 hMinimum run time, any configuration

Worker in a hard hat and headlamp climbing out of a confined-space hatch beneath a stencilled sign reading Danger, Confined Space, Entry by Permit

Three Honeywell Flex 5 Series detectors: a 4-way diffusion unit in front, a 6-way diffusion unit behind it and a 6-way pumped unit with sample inlets on the right — Flexible configuration supporting up to six gases
Front: 4-way diffusion · Rear: 6-way diffusion · Right: 6-way pumped

Configurations

One device. Many configurations.

The Flex 5 is designed as a single, modular platform that can be configured to meet different job requirements, without switching devices. It comes in 3 fundamental configurations: 4- and 6-way cartridge (diffusion), and 6-way cartridge with built in pump. The swappable cartridges let users change configurations with minimal effort, and a unit can be ordered or configured later as required by users with appropriate training.

Diffusion

4-way diffusion

Up to 5 gases

Size: 136.5 mm × 72.2 mm × 32.8 mm5.4 in × 2.8 in × 1.3 in
Weight: 273 g338 g with extended battery
Ingress: IP66 & IP68
Max run time: Up to 12 days continuousUp to 25 days continuous with extended battery

Diffusion

6-way diffusion

Up to 6 gases

Size: 158 mm × 72.2 mm × 32.8 mm6.2 in × 2.8 in × 1.3 in
Weight: 299 g364 g with extended battery
Ingress: IP66 & IP68
Max run time: Up to 12 days continuousUp to 25 days continuous with extended battery

Pumped

6-way pumped

Up to 6 gases

Size: 163 mm × 72.2 mm × 54.3 mm6.4 in × 2.8 in × 2.2 in
Weight: 363 g428 g with extended battery
Ingress: IP65
Max run time: Up to 1 day continuousUp to 2 days continuous with extended battery

Pumped only: the VOC (PID) sensor is available on the 6-way pumped cartridge, slot 6.

Size and weight with standard battery unless noted, and reference LEL NDIR, O2, CO, H2S sensors, excluding alligator clip. Maximum run times as new, typical 20°C use; minimum run time after 2 years is 12 hours. Run time varies with use, age, and configuration, with a minimum of 1 × 8 hour shift + 50 % (12 hours) in any configuration.

Configurable options include

Diffusion or pumped sampling
4, 5, or 6-gas configurations
Can be configured with a broad range of gas types
Support for advanced sensor technologies, including PID
Accessories that verify and validate automatically

Supports the daily demands of

Confined space entry teams
Utilities and municipal field crews
Oil and gas operations
Industrial maintenance and shutdowns
Technicians responsible for fleet readiness
Surveyors and inspectors
Fire, hazmat, and emergency response teams

Whether you’re clearing a space before entry, monitoring continuously during work, or capturing exposure data for reporting later, one platform lets an organization standardize on a single device while configuring it for a wide range of gas detection needs, reducing training time, spare inventory, and operational complexity.

Built on the proven BW Flex platform

The Honeywell BW Flex multi-gas detector with Bluetooth and i-Series sensor technology is also available from FarrWest.

View BW Flex

Sensor slots

Up to 4 × 1 Series + 2 × 4 Series

Up to 4 x 1 Series and 2 x 4 Series sensors may be selected from over 20 different types for a wide range of safety applications. Field-replaceable sensor cartridges let one device support multiple applications, reducing downtime, spares and service effort. Here is where each sensor format fits.

Cartridge slot mapIllustration · slot numbers

4-way diffusionSlots 1 to 4

11 Series21 Series31 Series41 Series

CO+H2S dual sensor: only available slot 3 on diffusion 4-way cartridge.

6-way diffusionSlots 1 to 6

11 Series21 Series31 Series41 Series54 Series64 Series

Slots 5 and 6 take 4 Series sensors.

6-way pumpedSlots 1 to 6

11 Series21 Series31 Series41 Series54 Series64 Series

VOC (PID): only available on 6-way pumped cartridge slot 6.

1 Series slot4 Series slotRestricted sensor available

Slots 1 to 4: all 1 Series sensors compatible with slots 1 to 4 on 4- and 6-way cartridges.
Slots 5 and 6: all 4 Series sensors compatible with slots 5 and 6 on 6-way cartridges.
Dual toxic: the CO+H2S sensor is only available slot 3 on diffusion 4-way cartridge.
PID: the VOC (PID) sensor is only available on 6-way pumped cartridge slot 6.
Restrictions of sensor combinations apply subject to cross sensitivities.
Sensing technology used may limit temperature and humidity operation.

1 SeriesSlots 1 to 4

LEL CB F/UFFlammable (%LEL)Catalytic bead
HC LEL NDIRHydrocarbon (%LEL)Non-dispersive infrared
NDIR CO₂Carbon dioxide (%VOL)Non-dispersive infrared
O₂Oxygen (%VOL)Lead-free, long life
CO-HCarbon monoxide (ppm)Electrochemical (low H₂ response)
CO+H₂SCarbon monoxide/hydrogen sulfideElectrochemical (dual toxic) · 4-way diffusion, slot 3

1 & 4 SeriesEither slot type

COCarbon monoxide (ppm)Electrochemical
Cl₂Chlorine (ppm)Electrochemical
HCNHydrogen cyanide (ppm)Electrochemical
H₂SHydrogen sulfide (ppm)Electrochemical
NONitric oxide (ppm)Electrochemical
NO₂Nitrogen dioxide (ppm)Electrochemical
SO₂Sulfur dioxide (ppm)Electrochemical

4 SeriesSlots 5 and 6, 6-way cartridges

VOC (PID)Volatile organic compounds (ppm)Photoionization (PID) · 6-way pumped, slot 6
NH₃Ammonia (ppm)Electrochemical
ClO₂Chlorine dioxide (ppm)Electrochemical
EtOEthylene oxide (ppm)Electrochemical
HClHydrogen chloride (ppm)Electrochemical
H₂Hydrogen (ppm)Electrochemical
HFHydrogen fluoride (ppm)Electrochemical
O₃Ozone (ppm)Electrochemical
COCl₂Phosgene (ppm)Electrochemical
PH₃Phosphine (ppm)Electrochemical

Typical units of measure given. %LEL, %VOL, ppm, umol/mol, mg/m3 also available subject to region. Ask us about cartridge configurations for the gases you need to monitor.

Automated workflow

Designed to reduce steps before entry

NFC enabled actionTAGS in the Flex 5 support automated assignment, configuration cloning, accessory checks, and permit-to-work workflows. Tags cover users, sampling accessories, bump and calibration cylinders, and locations.

Worker in a respirator and orange coveralls reviewing a clipboard beside an open manway

Pre-entry is where time is most often lost and where mistakes carry the most risk.

Flex 5 streamlines pre-entry through

1Automated assignment and configuration through NFC enabled action tags
2Configuration cloning across devices
3Accessory verification to ensure the right setup
4Guided workflows that support permit-to-work processes

The result is faster job starts, fewer manual checks, and greater confidence that procedures were followed correctly.

Scan · user

USER tag

Easy identification of users or change of service, e.g. “out for repair”.

Scan · accessory

ACCESSORY tag

Tag sampling accessories for simple verification of gas type compatibility and set operation automatically.

Scan · cylinder

BUMP tag

Initiate a bump test by scanning a gas cylinder tag, with full traceability and 100% validation.

Scan · cylinder

CALIBRATION tag

Read calibration gas cylinder set up and complete the “guided” calibration routine.

Scan · location

LOCATION tag

Check an asset name, item number, verify location, or entry to a confined space, all can be programmed.

Security

Encrypted tags

All actionTAGS are AES-128 bit encrypted or higher
User programmed via PC or mobile device software
Supports NTAG424 DNA and DESFire EV2(3)
Full boot load security and diagnostic check on start up

Connectivity

Connectivity on your terms

Not every job site supports constant connectivity. Not every team needs it. Data sharing and device management can be tailored to each scenario, whether readings are instantly relayed to a first responder in an emergency, or a surveyor sends updates to the control room once the device is docked. Choose the model that fits the job.

Model 01

Data Later

Capture readings and sync automatically when device is back in range.

Model 02

Data On Demand

Establish a temporary real-time connection during critical events or high-risk work.

Model 03

Data Now

Enable real-time visibility where infrastructure allows.

Illustration · visibility without forcing always on connectivity

On the device

WiredUSB-C 5V 1-2A device controlled
WirelessBluetooth® 5.X
ContactlessNFC 13.56MHz contactless technology
Tag securitySupports NTAG424 DNA and DESFire EV2(3) for maximum data security and encryption to avoid cyber-attacks

Paired with Honeywell software solutions, Flex 5 enables fast access to device data, fleet insights, and configurable compliance tools, without forcing always on connectivity.

Software

PC LiteWindows 11 · included

Included for fundamental system set up and configuration, and data extraction, at local point of use.

Device ConfiguratorMobile app · iOS, Android

The Flex 5 operates with the Device Configurator Mobile App, and actionTAGS are user programmed via PC or mobile device software.

Safety Suite 2.0Recommended for fleets

Recommended for centralised fleet management and custom report generation, across multiple locations. Paired with Safety Suite 2.0, Flex 5 extends beyond gas detection into connected safety management for fleets, workers, and safety leaders at scale.

Display, alarms & records

Clear information, at a glance

Clear readings for the wearer, alarms built for noisy environments, and a record that goes beyond event and data logs: the Flex 5 also captures configuration change history, calibration history and advanced diagnostic data.

A clear, easy-to-read display
Simple, glove-friendly operation
Stable sensor performance that builds trust in readings
Audible and visual alarms designed for noisy environments

Alarms

Visual, vibrating, audible 95 dB at 30 cm

3 x Instantaneous
TWA
STEL
Negative Drift
Over Limit
Battery
System Integrity

System integrityWhat the Flex 5 keeps

Event logCritical events
All system and sensor critical events with user acknowledgement where required.
Data log15–120 s interval
System and sensor specific readings at defined interval for 15-120 s (user configurable).
Configuration logFull change history
Factory default, instrument restore point (user configurable), current settings, with full change history.
Calibration historyLast 10 calibrations
Full calibration history of a given device up to and including last 10 calibrations.
Advanced diagnosticsMaintenance
System, sensor, battery, and user operational related log for maintenance and life time operation assistance.

Specifications

Key specifications

Download the datasheet under Service & resources for the full document.

Overview
Description	Highly modular, multi-gas portable gas monitor for detection of explosive, oxygen, and toxic gas hazards.
Sensors	Up to 4 x 1 Series and 2 x 4 Series sensors may be selected from over 20 different types for a wide range of safety applications.
Configurations	Available in 3 fundamental configurations of 4- and 6-way cartridge (diffusion), and 6-way cartridge with built in pump. Can be ordered or configured later as required by users with appropriate training. 4-way diffusion (up to 5 gases) 6-way diffusion (up to 6 gases) 6-way pumped (up to 6 gases)
Physical · standard battery
Size	4-way diffusion: 136.5 mm × 72.2 mm × 32.8 mm (5.4 in × 2.8 in × 1.3 in) 6-way diffusion: 158 mm × 72.2 mm × 32.8 mm (6.2 in × 2.8 in × 1.3 in) 6-way pumped: 163 mm × 72.2 mm × 54.3 mm (6.4 in × 2.8 in × 2.2 in)
Weight	4-way diffusion: 273 g 6-way diffusion: 299 g 6-way pumped: 363 g
Reference	With reference LEL NDIR, O2, CO, H2S sensors; excludes alligator clip
Environment
Ingress protection	Waterproof, independently tested IP66 & IP68 (diffusion), IP65 (pumped)
Humidity	Operating conditions dependent upon sensors. Generally 0-99%rH (non-condensing) is recommended

Standard battery
Battery run time	Varies with use, age, and configuration. Minimum run time is 1 × 8 hour shift + 50 % (12 hours) any configuration
Maximum (as new, typical 20°C use)	4-way diffusion: Up to 12 days continuous 6-way diffusion: Up to 12 days continuous 6-way pumped: Up to 1 day continuous
Minimum (after 2 years)	12 hours, all configurations
Extended battery
Weight	4-way diffusion: 338 g 6-way diffusion: 364 g 6-way pumped: 428 g
Maximum (as new, typical 20°C use)	4-way diffusion: Up to 25 days continuous 6-way diffusion: Up to 25 days continuous 6-way pumped: Up to 2 days continuous
Minimum (after 2 years)	12 hours, all configurations

Alarms
Alarms and type	Visual, Vibrating, Audible (95 dB at 30 cm), 3 x Instantaneous, TWA, STEL, Negative Drift, Over Limit, Battery, System Integrity
System integrity
Event log	All system and sensor critical events with user acknowledgement where required
Data log	System and sensor specific readings at defined interval for 15-120 s (user configurable)
Configuration log	Factory default, instrument restore point (user configurable), current settings, with full change history
Calibration history	Full calibration history of a given device up to and including last 10 calibrations
Advanced diagnostics	System, sensor, battery, and user operational related log for maintenance and life time operation assistance

Connectivity & software
Interfaces	USB-C 5V 1-2A device controlled, Bluetooth® 5.X, NFC 13.56MHz contactless technology.
Security	Supports NTAG424 DNA and DESFire EV2(3) for maximum data security and encryption to avoid cyber-attacks.
Software	Operates with Device Configurator Mobile App (iOS, Android), Safety Suite 2.0, and PC Lite (Windows 11). PC Lite included for fundamental system set up and configuration, and data extraction, at local point of use. Safety Suite 2.0 recommended for centralised fleet management and custom report generation, across multiple locations.
actionTAGS
Start up	Full boot load security and diagnostic check on start up
Tags	USER tag: Easy identification of users or change of service e.g. “out for repair” ACCESSORY tag: Tag sampling accessories for simple verification of gas type compatibility and set operation automatically BUMP tag: Initiate a BUMP test by scanning a gas cylinder tag with full traceability and 100% validation CALIBRATION tag: Read calibration gas cylinder set up and complete the “guided” calibration routine LOCATION tag: Check an asset name, item number, verify location, or entry to a confined space, all can be programmed
Encryption	All actionTAGS are AES-128 bit encrypted or higher. User programmed via PC or mobile device software

Gas · short ref.	Sensing technology	Sensor format
Flammable (%LEL)LEL CB F/UF	Catalytic bead	1 Series
Hydrocarbon (%LEL)HC LEL NDIR	Non-dispersive infrared	1 Series
Carbon dioxide (%VOL)NDIR CO2	Non-dispersive infrared	1 Series
Volatile Organic Compounds (ppm)VOC (PID)	Photoionization (PID)	4 Series · 6-way pumped, slot 6 only
Oxygen (%VOL)O2	Lead-free, long life	1 Series
Ammonia (ppm)NH3	Electrochemical	4 Series
Carbon Monoxide (ppm)CO-H	Electrochemical (low H2 response)	1 Series
Carbon Monoxide (ppm)CO	Electrochemical	1 & 4 Series
Carbon Monoxide/Hydrogen SulfideCO+H2S	Electrochemical (dual toxic)	1 Series · diffusion 4-way, slot 3 only
Chlorine (ppm)Cl2	Electrochemical	1 & 4 Series
Chlorine Dioxide (ppm)ClO2	Electrochemical	4 Series
Ethylene Oxide (ppm)EtO	Electrochemical	4 Series
Hydrogen Chloride (ppm)HCl	Electrochemical	4 Series
Hydrogen (ppm)H2	Electrochemical	4 Series
Hydrogen Cyanide (ppm)HCN	Electrochemical	1 & 4 Series
Hydrogen Fluoride (ppm)HF	Electrochemical	4 Series
Hydrogen Sulfide (ppm)H2S	Electrochemical	1 & 4 Series
Nitric Oxide (ppm)NO	Electrochemical	1 & 4 Series
Nitrogen Dioxide (ppm)NO2	Electrochemical	1 & 4 Series
Ozone (ppm)O3	Electrochemical	4 Series
Phosgene (ppm)COCl2	Electrochemical	4 Series
Phosphine (ppm)PH3	Electrochemical	4 Series
Sulfur Dioxide (ppm)SO2	Electrochemical	1 & 4 Series

Typical units of measure given. %LEL, %VOL, ppm, umol/mol, mg/m3 also available subject to region. All 1 Series sensors compatible with slots 1 to 4 on 4- and 6-way cartridges; all 4 Series sensors compatible with slots 5 and 6 on 6-way cartridges. Restrictions of sensor combinations apply subject to cross sensitivities. Sensing technology used may limit temperature and humidity operation. Ask us about ranges and part numbers for the gases you need.

Service & resources

Engineered for service, scale and uptime

The Flex 5 is designed with technicians in mind, because uptime depends on serviceability. FarrWest is a Honeywell Authorized Service Provider for BW and RAE Systems gas detection. Not every service level is available for every product; call us to confirm coverage for the Flex 5 Series.

01Modular sensor cartridges

02Faster access for maintenance and inspection

03Reduced device downtime during servicing

04Fleet workflows that scale across sites and regions

FarrWest service

Honeywell warranty service

FarrWest is a Honeywell Authorized Service Provider for BW and RAE Systems gas detection. Not every service level is available for every product; call us to confirm coverage for the Flex 5 Series.

Warranty service FarrWest service

Calibration & repair

Functional checks and certified calibration on the manufacturer’s required cycle, with every certificate stored against the unit’s serial number. Back in service in 48–72 hours typical.

Repair Depot Honeywell

Flex 5 Series datasheet

Features, technical specifications, configurations and the full sensor list.

PDF · Honeywell

FAQ

Questions we get on the phone

Which configurations does the Flex 5 Series come in?

Three fundamental configurations: 4-way diffusion (up to 5 gases), 6-way diffusion (up to 6 gases) and 6-way pumped (up to 6 gases). A unit can be ordered or configured later as required by users with appropriate training.

Can one unit work as both a wearable and a pumped sampler?

Yes. Thanks to its modular design, the Flex 5 can serve as both a pumped device for sampling in confined spaces and as a wearable for personal protection, all within the same base unit. The swappable cartridges let users change configurations with minimal effort.

Which gases can it monitor?

Up to 4 x 1 Series and 2 x 4 Series sensors may be selected from over 20 different types, from catalytic bead and NDIR combustibles, NDIR CO2 and oxygen to electrochemical toxic sensors and a PID for VOCs. The VOC (PID) sensor is only available on the 6-way pumped cartridge, slot 6. The full list is in the sensor slots section. Ask us about configurations for the gases you need.

Does it need a constant connection?

No. Choose the model that fits the job: Data Later captures readings and syncs automatically when the device is back in range; Data On Demand establishes a temporary real-time connection during critical events or high-risk work; Data Now enables real-time visibility where infrastructure allows. On the device: USB-C, Bluetooth® 5.X and NFC 13.56MHz.

Which software comes with it?

PC Lite (Windows 11) is included for fundamental system set up and configuration, and data extraction, at local point of use. The Flex 5 also operates with the Device Configurator Mobile App (iOS, Android) and with Safety Suite 2.0, which is recommended for centralised fleet management and custom report generation across multiple locations.

What are actionTAGS?

NFC enabled tags that support automated assignment, configuration cloning, accessory checks, and permit-to-work workflows: USER, ACCESSORY, BUMP, CALIBRATION and LOCATION tags. For example, you initiate a bump test by scanning a gas cylinder tag, with full traceability and 100% validation. All actionTAGS are AES-128 bit encrypted or higher, and user programmed via PC or mobile device software.

How long does the battery last?

Run time varies with use, age, and configuration; the minimum is 1 × 8 hour shift + 50 % (12 hours) in any configuration. As new, at typical 20°C use, the standard battery gives up to 12 days continuous on the 4-way and 6-way diffusion units and up to 1 day on the 6-way pumped unit; the extended battery gives up to 25 days and up to 2 days. Minimum after 2 years is 12 hours.

Is it waterproof?

Waterproof, independently tested IP66 & IP68 (diffusion) and IP65 (pumped).

How does it relate to the BW Flex?

Honeywell built the Flex 5 Series on the proven BW Flex platform. The Honeywell BW Flex is also available from FarrWest.

What service does FarrWest offer?

FarrWest is a Honeywell Authorized Service Provider for BW and RAE Systems gas detection, and our Repair Depot in San Antonio, Texas offers calibration and repair. Not every service level is available for every product, so see Honeywell warranty service or call 210.566.1857 to confirm coverage for the Flex 5 Series.

Why FarrWest

Buying from FarrWest

Cooperative contracts

Next step

Configure a Flex 5 for your fleet

Ask us about gas selection, diffusion or pumped sampling, and connectivity options for your team.