Area gas monitor - BM25

The Oldham BM25 area gas monitor

The BM25 area gas monitor is a multigas detector that combines all the benefits of a fixed gas detector in a portable device, rugged and easy to use equipment. This area monitor can detect up to 5 gases simultaneously in a large range of different sensors. 

The Oldham area gas monitor features a high visibility 360° flashing light coupled to a two-way 103 dB sounder. STEL and TWA measurements are available as well as data logging up to 4 months (in 5 gas configuration). The BM25 batteries can run continuously during more than 170 hours depending on the configuration for a short charging time (4.30 hours only). 

BM25 area gas monitor technical specifications

• Major gases detected: 
  AsH3, B2H6, C2H4O, Cl2, CO, CO2, COCl2, F2, H2S, HCl, HCN, HF, N2H4, NO, NO2, NH3, O2, O3, PH3, SiH4, SO2, VOC (volatile organic compounds) and combustible gases (any flammable gas).
• Sensors: setting-free pre-calibrated smart sensors. Sensor and parameters automatic recognition (alarm, wear rate …)
• Multigas detection system: natural diffusion or pump versions
• Display: Large graphic backlit LCD. FLIP FLAP function (display reversal)
• Proper operation control:
  - Self-zero: Upon start-up or on demand
  - Self-check upon commissioning
  - No sensor stabilization time
• Gas alarms:
  - On display, clear message per channel
  - Audiovisual signals depending on alarm type
  - Alarm acknowledgment according to safety rules
• Alarm levels:
  - 2 instant thresholds per channel
  - Toxic gas STEL/TWA (average value upon 15 minutes or 8 hours)
  - High and low alarm thresholds for oxygen (2 optional low thresholds)
• Visual indicators: 20 ultra-bright LEDs that can be seen from anywhere and protected by sturdy metal elements
• Two-way sounder: 103 db at 1m
• Adjustable inputs/outputs:
  - 2 inputs: 1 logic input for remote acknowledgement + 1 logic “knuckle” or “alarm report” or “interconnection” input
  2 logic relay output: 1 fault relay output + 1 gas alarm output
  - 1 specific input/output: 4-20mA, RS485…
• Protection: IP 66 certified
• Weight: approx. 6.8 kg / Dimensions: L 180 x H 467 x D195
• Certifications: 
  - II 1GD EEx ia IIC T4
  - II 2 GD EEx  ia d IIC T4 (with CO2 sensor) 
• Power source: NiMH battery pack
  - Charger: integrated and smart, powered in 12/30VDC or 110VAC,220VAC
  - Power supply in zone 0,1,2 possible through trickle charge
  - Charging time: 4 hours and a half
  - Run time: Example for EXPLO/O2/TOX1/TOX2 configuration: 100h

The well-known BM25 area gas detector

The BM25 area gas monitor from Oldham is the most known on the market. Most commonly used in breweries and on offshore platforms, it can also be found on construction and  public work sites. The most commonly used configuration is the 4 gas version: combustible gas, oxygen, hydrogen sulfide and carbon monoxide.