Cart (
Overview
Sulfur dioxide is a gas that catches workers off guard more often than most safety managers would like to admit. It has a sharp, distinctive smell at higher concentrations — but by the time the odour is clearly noticeable, exposure may already be at a level that causes respiratory irritation. In petroleum refining, pulp and paper mills, metal smelting operations, and chemical manufacturing facilities, SO2 is a known and ongoing hazard that requires continuous personal monitoring, not periodic atmospheric checks.
The IGD BELLMINI SO2 Portable Single Gas Detector is a personal clip-on monitor that continuously tracks sulfur dioxide concentration across the 0–20 PPM detection range, delivering an immediate triple alarm the moment levels breach configured thresholds. It provides protection wherever the worker is — not just at fixed monitoring points installed at the perimeter of a hazard zone.
Built by International Gas Detectors (IGD), a UK specialist whose entire business is industrial gas detection, the BELLMINI SO2 brings together ATEX Zone 0 certification, a 2-year battery life without charging, and the BELLCONNECT Bluetooth app in a 105g wearable unit. That combination is what differentiates it from the majority of portable SO2 detectors in this price class — most offer the detection capability, but not the app-based compliance management and maintenance-free battery life together in the same device.
Key Features
Dedicated SO2 Detection — 0 to 20 PPM
The BELLMINI SO2 monitors sulfur dioxide across the 0–20 PPM range with a 20-second toxic gas response time. The OSHA permissible exposure limit for SO2 is 5 PPM as a TWA and 5 PPM as a STEL — meaning this detector covers the full range of occupationally relevant concentrations from threshold to ceiling. In refineries and smelting environments, catching SO2 accumulation at 1–3 PPM gives workers and supervisors time to act before concentrations reach acutely hazardous levels.
Triple Alarm System — Audible, Visual and Vibration
When SO2 levels breach configured thresholds, all three alarm channels activate simultaneously: a 100dB audible buzzer, multi-LED visual alerts, and a vibrating alarm. In refinery environments, smelter floors, and paper mill processing areas — where background noise is consistently high and workers wear hearing protection — a single-channel alarm is not a reliable safety mechanism. The triple system ensures the warning is received regardless of operating conditions. Alarm levels cover Low, High, TWA, and STEL.
2-Year Battery Life — No Charging Required
A 3.6V lithium battery runs the BELLMINI SO2 for 24 months without recharging. For facilities running continuous operations across multiple shifts — refineries, smelters, paper mills — removing the daily charging cycle eliminates a consistent operational failure point. A built-in confidence beep periodically confirms the unit is live and operational without needing a screen check.
IP68 Weatherproof and Dustproof
Full dust ingress protection and water submersion rating. SO2 environments are often hot, humid, and corrosive — cooling tower areas, acid plant environments, and flue gas handling zones are all conditions that degrade lesser devices. The BELLMINI’s IP68 housing is built to function in those conditions continuously without protective cases or special handling.
BELLCONNECT Bluetooth App
Via Bluetooth Low Energy or NFC tap within 10 metres, the BELLCONNECT app provides complete remote device management: calibration, bump testing, alarm setpoint adjustment, device-to-worker assignment, and access to up to 200 event logs and 5,000 data records from a smartphone. Calibration certificates are generated automatically — removing manual documentation from HSE teams managing SO2 compliance across large industrial sites.
SAFE Mode Display
When no SO2 is detected above alarm thresholds, the LCD displays “SAFE” — a clear visual confirmation before entering process areas, confined spaces, or maintenance zones where sulfur dioxide may be present. In refineries and chemical plants, pre-entry atmosphere confirmation is a procedural requirement, and SAFE mode supports that directly.
One-Button Operation
All primary device functions operate through a single button — no menus, no multi-step sequences. Operable with gloves on and in situations where worker attention needs to remain on the process task. In high-hazard environments, device simplicity is a safety feature in itself.
Replaceable Sensor and Battery
Both the SO2 sensor and the battery are field-replaceable on-site without returning the unit. When the sensor reaches end-of-life, a replacement is installed directly. This extends the usable device lifespan across multiple sensor cycles and keeps long-term per-unit costs predictable across a multi-year deployment.
Technical Specifications
Model: BELLMINI
Target Gas: Sulfur Dioxide (SO2)
Detection Range: 0–20 PPM
Weight: 105g (with belt clip)
Display: FSTN LCD (1.6 inch)
Battery Life: 24 months (3.6V Lithium, size 2/3 AA)
IP Rating: IP68
Alarm Types: Visual (LED), Audible (100dB@10cm), Vibration — Low, High, TWA, STEL
Wireless: Bluetooth Low Energy (BLE), NFC
Response Time: 20 seconds (Toxic Gas)
Data Logging: Up to 200 alarm events, 5,000 data logs
Humidity Range: 5% to 95% RH (non-condensing)
Safety Approvals: ATEX, IECEx, KCs
App: BELLCONNECT (iOS and Android)
Benefits
Protection that follows the worker into every zone. SO2 hazards in refineries and smelters are not confined to a single location — process upsets, fugitive emissions, and maintenance activities create exposure across multiple areas simultaneously. The BELLMINI SO2 provides continuous personal protection regardless of where the worker moves during the shift.
Compliance documentation without manual effort. The BELLCONNECT app generates timestamped calibration certificates and bump test records automatically. For sites operating under regulatory oversight for SO2 emissions and worker exposure, that documentation is always current, correctly attributed, and immediately available for inspection.
No charging infrastructure across large or remote sites. A 24-month battery life means no charging rotation, no infrastructure requirement, and no risk of a monitor entering service with insufficient charge. For large refinery or mining sites where charging points are not always accessible, this is a practical operational advantage.
Individual SO2 exposure records tied to named workers. Device-to-worker assignment through the BELLCONNECT app links sulfur dioxide exposure data to a named individual. In the event of a respiratory health claim, regulatory investigation, or internal incident review, the records are specific, dated, and immediately retrievable.
Lower total cost of ownership across a deployment cycle. Field-replaceable sensors extend the device body lifespan across multiple sensor lifetimes. For procurement managers running 5-year total cost comparisons, this produces a materially better cost position than alternatives requiring full unit replacement at sensor end-of-life.
Who It’s For
The HSE Manager at a Petroleum Refinery or Smelting Operation
You’re responsible for personal SO2 protection across a large site with multiple process units, each carrying its own exposure risk profile. You need monitors that are always operational across rotating shifts, generate compliance records without manual effort, and can be managed across a fleet from a central interface. The BELLMINI SO2 and BELLCONNECT platform are built for that operational scale.
The Process Operator Working in Sulfur Recovery or Acid Plant Areas
You work in areas where SO2 is generated as a direct process output or byproduct — sulfur recovery units, Claus plants, acid gas treatment systems. You need a monitor that clips on at the start of the shift, requires nothing from you during the day, and gives you an unmistakable alarm if SO2 levels climb. The BELLMINI’s triple alarm and 2-year battery mean it’s always ready without any daily setup from you.
The Procurement Manager Specifying Monitors for a Multi-Site Industrial Operation
You’re standardising personal gas detection across multiple facilities in a refining, mining, or chemical group. You need ATEX certification for hazardous area compliance, IP68 durability for harsh site conditions, a maintenance-free battery to simplify fleet management, and app-based compliance documentation to satisfy your HSE reporting requirements. The BELLMINI SO2 addresses all four in a single specification.
Possible Applications
- Petroleum refining — Sulfur recovery units, hydrotreating, and Claus plant operations where SO2 is a direct process gas
- Metal smelting and ore processing — Copper, nickel, lead, and zinc smelters where SO2 is produced from sulphide ore roasting
- Pulp and paper manufacturing — Kraft process recovery boilers and bleaching operations generating SO2 and other sulphur compounds
- Sulfuric acid production — Contact process plants where SO2 is a primary intermediate in concentrated acid manufacture
- Power generation from coal or heavy fuel oil — Boiler and flue gas handling areas where SO2 is produced as a combustion byproduct
- Wastewater treatment — Facilities using sodium bisulphite or SO2 for dechlorination of treated effluent
- Food and beverage production — SO2 used as a preservative in wine, dried fruit, and food processing environments
- Chemical plant maintenance and turnarounds — Confined space entry and equipment inspection in process areas with residual SO2
Trust and Certifications
ATEX: Ex II 1G Ex ia IIC T4 Ga
ATEX is the European standard for equipment used in explosive atmospheres. Zone 0 classification — the most stringent level — confirms the BELLMINI SO2 is approved for continuous use in locations where explosive gas is present continuously. For refineries, chemical plants, and smelting operations with ATEX zone classifications, this certification covers the highest hazard designation.
IECEx: Ex ia IIC T4 Ga
The globally accepted equivalent of ATEX, recognised in over 50 countries including Australia, the Middle East, and Asia-Pacific. For organisations operating across multiple countries, IECEx removes the need for separate national certifications in most jurisdictions — particularly relevant for mining and refining groups with international operations.
KCs Certified
Korean industrial safety certification required for deployment in South Korean facilities. Accepted across a number of other Asian industrial markets — relevant for refining and petrochemical operations across the Asia-Pacific region.
2-Year Manufacturer Warranty
Standard device warranty for 24 months from purchase. Sensor warranty terms are subject to individual sensor data. For a device deployed in daily SO2 environments, a 2-year warranty provides meaningful procurement-stage assurance for the capital investment.
IGD — International Gas Detectors
Based in Stockport, UK, IGD’s complete engineering focus is gas detection — fixed and portable systems for industrial clients worldwide. The BELLMINI is not a repurposed consumer instrument; it is the product of decades of specialist development by a company for whom industrial gas detection is the entire business.
Accessories and Variants
BELLCONNECT App (Free — iOS and Android)
Essential for safety teams managing multiple devices across large sites or multi-facility operations — calibration, bump testing, alarm configuration, data logging, compliance reporting, and worker assignment from one smartphone interface.
Alligator/Belt Clip (Included)
Positions the sensor correctly in the breathing zone throughout the shift. Attaches securely to work clothing, PPE, harnesses, or equipment straps without restricting movement in process environments.
Replacement SO2 Sensor Modules
Field-swappable when the sulfur dioxide sensor reaches end-of-life. Keeps the device body in continuous service and avoids the cost and lead time of full unit replacement.
Calibration Gas Kits
Available separately for on-site bump testing and full calibration. The BELLCONNECT app guides the process and generates a dated calibration certificate automatically on completion.
Available BELLMINI Variants
POR-GDIS-SO2 — Sulfur Dioxide (SO2) | 0.1–20 PPM
POR-GDIS-CO — Carbon Monoxide (CO) | 1–1000 PPM
POR-GDIS-H2S — Hydrogen Sulfide (H2S) | 0.1–100 PPM
POR-GDIS-O2 — Oxygen (O2) | 0.1–30% VOL
POR-GDIS-NH3 — Ammonia (NH3) | 1–100 PPM
POR-GDIS-HCN — Hydrogen Cyanide (HCN) | 1–50 PPM
POR-GDIS-HCL — Hydrogen Chloride (HCl) | 0–15 PPM
POR-GDIS-NO — Nitric Oxide (NO) | 0–250 PPM
POR-GDIS-PH3 — Phosphine (PH3) | 0–20 PPM
POR-GDIS-COEX — Carbon Monoxide EX | 1–2000 PPM
Get in Touch
If sulfur dioxide monitoring is part of your site’s safety programme — whether for a refinery, smelter, pulp mill, or chemical processing operation — the BELLMINI SO2 is worth evaluating against your current personal protection setup.
Contact Alright Engineering Solutions to request a formal quote, arrange a product demonstration, or discuss volume pricing for team or fleet deployments.
📍 3791 Jalan Bukit Merah #06-01, E-Centre @ Redhill, Singapore 159471
