How to Choose Ammonia Sensors for Livestock Farms

In large-scale livestock farms, ammonia (NH₃) is one of the most common and harmful gases. It mainly originates from microbial decomposition of animal manure, urine, and feed residues, especially in poorly ventilated, high-density barns where manure is not promptly removed. Prolonged exposure to high ammonia levels can seriously affect animal growth, feed conversion efficiency, immunity, and can trigger respiratory diseases or even mass mortality.

Ammonia also poses a fire and explosion hazard: at concentrations of 16%–25% vol, it may explode if exposed to open flames at room temperature. Therefore, scientific, real-time, and reliable ammonia monitoring in animal houses has become a critical requirement for modern farm biosecurity and production management.

Ammonia Hazards and Concentration Thresholds

Studies and practical experience indicate a clear dose-effect relationship between ammonia concentration and animal health:

• 10–20 ppm: mild irritation, reduced feed intake, slower growth, slight immunity reduction.
• 20–50 ppm: eye tearing, nasal discharge, respiratory mucosa damage, weaker vaccine response; especially noticeable in broilers and ducks.
• 50–75 ppm: significant increase in respiratory diseases; pigs may develop atrophic rhinitis; feather quality declines in poultry.
• 75–100 ppm: obvious loss of appetite, weight loss, higher mortality, severe production impact.
• >100 ppm: acute toxicity risk; severe respiratory distress and potential rapid mortality.

Tolerance varies slightly among species, but a common industry guideline is to keep ammonia below 20 ppm under normal conditions, and not exceed 50 ppm during peaks for healthy farming.

Key Considerations for Ammonia Sensor Selection

Choosing an appropriate ammonia sensor for farms requires attention to the following factors:

1. Measurement principle & interference resistance: Common principles include electrochemical, laser, PID, and MOS sensors. Due to humidity, dust, H₂S, and mercaptans in barns, electrochemical or laser sensors are recommended. Electrochemical sensors are cost-effective and mature; laser sensors offer better interference resistance and longer lifespan.
2. Range & resolution: Typical farm ranges are 0–100 ppm or 0–200 ppm, with resolution of 1 ppm or 0.1 ppm for low-level detection.
3. Temperature & humidity adaptability: Barn temperatures fluctuate from -10℃ to 40℃, humidity 40–95% RH. Full-range temperature and humidity compensation is essential.
4. Response time & stability: Ideally ≤60 seconds, with minimal zero and span drift to reduce calibration needs.
5. Output & system integration: Support 4-20mA, RS485 (Modbus), 0–5V, TTL, for connection to controllers, IoT platforms, or PLCs.
6. Protection & installation suitability: IP65+, corrosion-resistant, dustproof, waterproof for humid, ammonia-rich, dusty environments.
7. Calibration-free & plug-and-play: Pre-calibrated modules reduce technical burden for farm staff.
8. Cost-effectiveness & support: Balance performance with price, lifespan, spare parts availability, and technical service.

Features of Nexisense SGA-400/700 Ammonia Sensors

The Nexisense SGA-400/700 series is optimized for livestock, agriculture, and environmental monitoring. Using imported core sensors, amplified signals, intelligent computation, three-point temperature & humidity compensation, and high-precision calibration, the modules provide a fully integrated, ready-to-use solution.

Key advantages:

• Compact size, suitable for embedding in controllers or wall-mounting.
• Factory pre-calibrated; no user calibration required.
• Standard 0–5V analog output (adjustable) + TTL digital output, compatible with PLC, DCS, MCU, or IoT devices.
• Full-range three-point temperature and humidity compensation for accurate readings.
• High stability and low zero drift, suitable for continuous monitoring.
• Applicable to animal houses, composting areas, wastewater zones, and other farming environments.

Typical Deployment and Installation Tips

1. Sensor placement: • Height 30–80 cm (animal breathing zone)
• Away from manure pits, ventilation inlets, and feed troughs
• 3–8 points per barn depending on size and zones

2. Installation method: • Wall-mounted or suspended, probe downward or horizontal
• Protective cover to prevent pecking or contamination

3. System integration: • NH₃ >20 ppm → increase fan speed or open wet curtains
• NH₃ >50 ppm → alarm + increase ventilation
• NH₃ >75 ppm → audible & visual alarm + SMS alert

4. Maintenance: • Check probe cleanliness every 3–6 months; clean with soft brush or compressed air
• Annual verification with standard gas
• Monitor sensor lifespan (3–5 years typical)

Practical Benefits

• Respiratory diseases reduced by 30–60%
• More stable vaccine response and antibody levels
• Improved daily weight gain and feed conversion
• Reduced veterinary and medication costs
• Lower risk of ammonia-induced sudden mortality

FAQ

1. Safe ammonia concentration? ≤20 ppm normally; peak ≤50 ppm; >75 ppm dangerous.
2. Electrochemical vs laser sensors? Electrochemical is cost-effective and fast; laser is more interference-resistant and longer-lasting.
3. Why temperature/humidity compensation? Prevents >30% measurement error in winter or high humidity.
4. Is field calibration needed? Factory calibrated, plug-and-play.
5. How to connect outputs? 0–5V analog and TTL digital to MCU, PLC, or IoT terminals.
6. Can manure or dust damage sensor? Use protective cover and regular cleaning; IP65+ protection recommended.
7. How often to verify accuracy? Annual standard gas check, monitor data trends.
8. Benefits after installation? Lower disease rates, improved growth, reduced medication, decreased mortality, higher farm efficiency.

Conclusion

Ammonia monitoring has become essential for high-efficiency, low-disease, low-medication livestock farming. Selecting a responsive, stable, interference-resistant, integrable, calibration-free ammonia sensor is the first step to precise environmental control. The Nexisense SGA-400/700 series provides modular, plug-and-play, cost-effective solutions for small to medium farms, protecting animals from ammonia hazards, improving health and comfort, and enhancing economic returns. Proper selection, deployment, and maintenance make ammonia monitoring a reliable pillar for green, efficient livestock operations.