HBr Tank Area Gas Detection Solution: Essential Safety Barrier for Chemical Plants

In fine chemicals, pharmaceutical intermediate synthesis, dye production, and organobromine preparation, HBr, as a key raw material and catalyst, is used in large quantities. However, this colorless gas with a strong irritating odor poses serious hazards. HBr vapor strongly irritates and corrodes eyes, respiratory tract, and skin; upon contact with water, it forms hydrobromic acid, increasing corrosiveness. A leak may cause acute poisoning of personnel, severe equipment corrosion, and serious environmental pollution.

Therefore, in critical areas such as storage tanks, filling stations, and reactor zones, establishing a reliable and fast-response online gas detection system has become a baseline requirement for chemical plant safety. The Nexisense SGA-500 series provides a professional solution tailored for high-risk, highly corrosive environments.

Hazard Characteristics and Leak Risks of HBr

HBr (CAS 10035-10-6) is a colorless gas at normal temperature and pressure, with a density 2.8 times that of air, tending to accumulate in low areas. Its main hazards include:

• Strong irritation and corrosiveness: low concentrations cause tearing, runny nose, and throat burning; high concentrations may lead to pulmonary edema, chemical pneumonia, or death.

• Violent reaction with water: forms hydrobromic acid, corroding metals, pipes, and non-metal materials.

• Toxicity: extremely toxic chemical, very high acute inhalation toxicity.

According to GBZ 2.1-2019, the maximum allowable concentration (MAC) of HBr is 10 mg/m³ (~3 ppm). International standards are stricter: ACGIH TLV Ceiling 2 ppm, OSHA PEL 3 ppm (8-hour TWA), NIOSH REL Ceiling 3 ppm. Even minor leaks pose serious threats to workers.

In practice, HBr is stored as a liquid under low temperature and high pressure or supplied in cylinders. Valve leaks, pipe corrosion, operational errors, or accidents like earthquakes can release gas. Due to its high density, leaks form high-concentration hazard zones near the ground, which manual inspections often fail to detect early.

Why Tank Areas Must Use Fixed Online Detection Systems

Handheld or portable detectors are suitable for emergency inspections but cannot provide 24/7 continuous, blind-spot-free monitoring. Online fixed systems offer irreplaceable advantages:

• Real-time continuous monitoring, capturing early micro-leaks

• Automatic audible and visual alarms to alert personnel immediately

• Integration with fans, scrubbers, and emergency shut-off valves for automatic leak response

• Data upload to control rooms or safety platforms, supporting remote monitoring, trend analysis, and historical tracking

Given HBr’s high toxicity and strong corrosiveness, detection systems must be corrosion-resistant, wide-temperature capable, and water/dustproof. Nexisense SGA-500 is developed to meet these rigorous requirements.

Core Technical Advantages of Nexisense SGA-500

• High-performance imported electrochemical sensor, optimized for HBr and resistant to interference

• Measurement ranges: 0–10 ppm / 0–30 ppm / 0–50 ppm, covering occupational limits and leak alerts

• High resolution: 0.01 ppm, detecting minimal leaks early

• Fast response: T90 ≤ 60 s

• Power supply: DC 24V, low consumption, compatible with industrial power

• Signal output: 4–20 mA, RS485 Modbus RTU, seamless PLC/DCS integration

• Protection: IP65+, explosion-proof version available (Ex d IIC T6 Gb)

• Local display and alarm: HD LCD shows concentration, temperature, and humidity, ≥85 dB audible/visual alarm

• Corrosion-resistant design: probe coated for long-term resistance to acidic gases

Compact structure, easy installation and maintenance, ideal for long-term stable operation in chemical tank areas.

Scientific Planning and Layout of HBr Detection Points

• Close to potential leak sources: tank bottoms, valve sets, pipe flanges, pumps

• Consider gas settling: install 0.3–1.0 m above ground

• Cover main operating areas: platforms, inspection aisles, loading/unloading stations

• Number of points: 4–8 for small/medium tanks; 10–20 for large tanks, forming grid monitoring

• Avoid strong direct airflow, exhaust vents, and protect probes from splashes or pooled liquid

Building a Complete HBr Alarm and Emergency Response System

• Multiple inputs: integrate multiple SGA-500 detectors

• Tiered alarms: level 1 warning (e.g., 1 ppm), level 2 mandatory alarm (near or above limit)

• Automatic linkage: fans, scrubbers, valve closure upon threshold exceedance

• Data management: historical curve review, alarm log export, monthly report generation

Typical flow: detector senses leak → alarm → controller sends signal → fan forces exhaust → gas directed to neutralization or scrubber tower, protecting personnel and minimizing environmental impact.

Installation, Usage, and Daily Maintenance

• Secure detector firmly, avoiding vibrations

• Shielded signal cables to prevent electromagnetic interference

• Initial calibration with standard gas: zero and span

• Monthly visual inspection of casing and probe cleanliness

• Quarterly zero/span calibration

• Sensor lifespan: 2–3 years; replace if drift or slow response occurs

• Do not wash probe with water; use specialized neutral cleaner

FAQ

1. How to set alarm thresholds? Level 1: 1–2 ppm (30–60% of occupational limit), Level 2: 5–8 ppm (near GBZ 2.1 limit).

2. Stability in high humidity or low temperature? Built-in temp/humidity compensation, -20℃ to +50℃, 0–95% RH no condensation.

3. How to link with scrubbers or fans? Via relay or Modbus signals, controlling valves and fans automatically.

4. Sensor lifespan? ~2–3 years under normal use; accelerated by high concentration or contamination, device alerts replacement.

5. Coverage area? 5–10 m radius; large tanks require distributed multi-point layout.

6. Causes of false alarms and solutions? Probe contamination, nearby acidic gases, power fluctuations, or expired calibration. Cleaning and recalibration reduce false alarms.

7. Explosion-proof certification required? Yes, Ex d IIC T6 Gb available, recommended for zone 1/2 hazardous areas.

8. How to use data for safety and compliance? Store/export data: concentration trends, alarm logs, monthly reports for occupational health evaluation and audits.

Conclusion

HBr detection is not just equipment, but the core of a complete safety protection system. SGA-500 combined with SGA-800 provides high reliability, easy integration, and fast response.

Deploying professional gas monitoring systems prevents leaks, protects lives, reduces environmental risks, and enhances compliance. Technology should shield every company handling HBr.

If you face safety upgrades for HBr storage and transport, contact us to design the solution best suited to your facility.