Photoacoustic gas monitor with multipoint sampler and dosing unit for air-exchange analyses and ventilation-efficiency measurements using the tracer-gas technique.

The photoacoustic gas monitor INNOVA 1412i is a highly accurate quantitative field gas monitor, the measurement principle is based on the photoacoustic infrared detection method. It can selectively measure the concentration of up to 5 component gases (TOCs, Formaldehyde, CO, CO2, and Freon) and water vapour in the air. Multipoint Sampler and Doser INNOVA 1303 offers air-exchange analyses and ventilation-efficiency checks are easily performed using the dosing facilities. Tracer-gas (Freon) is delivered through tubing to 'label' the air in up to 6 different locations, each being up to 50 meters away; the amount of tracer-gas delivered is automatically calculated. The 'labelled' air is then sampled again using the sampler system, and delivered to the INNOVA 1412i for analysis. Dosing is done by giving eithe constant dose of tracer gas to each location , or by maintaining a constant concentration of tracer gas at each location

Detection Limit: gas-dependent, but typically in the ppb region. Influence temperature: ±10% of detection limit. Influence of pressure: ±0.5% of detection limit. Repeatability: 1% of measured value. Range drift: ±2.5% of measured value per 3 months. Influence of temperature: 0.3% of measured value. Influence of pressure: -0.01% of measured value. Interference: The 1412 automatically compensates for temperature and pressure fluctuations in its analyses cell, and compensate for water vapour in the air sample. The device can cross-compensate for the interferent. Acoustic Sensitivity: not influenced by external sound. Internal data storage capacity: Dependent on the number of gases being measured. Sufficient for a 12-day monitoring task, monitoring 5 gases and water vapour every 10 min. Dimensions: height - 175mm, width - 395 mm, depth - 300 mm, weight - 9 kg. Sampling/dosing system: The following pressure and volume-flow data assumes the use of tubing of length 50 m and Internal diameter 3mm. Pump Performance: working pump suction 20kPa. Minimum pressure, blocked airways: 40 kPa. Volume flow rate of supplementary air per dosing channel 4 ml/s. Tracer-gas Supply: From pressurized cylinder. Supply pressure: 300-450 kPa absolute. Volume flow rate of tracer-gas at supply pressure of 300kPa absolute: small- approximately 0.5ml/s, medium - approximately 3.0ml/s, large - approximately 15.0ml/s. Max, time taken to deliver a dose of tracer-gas over a 50m distance through standard tubing: 1 minute. Internal Volume of Doser System: 70ml. Accuracy of Dosage Calculation: ±2%. Set-up parameters: Three set-up parameters are used. Dosing Time-out: specifies the maximum time for which the 1303 will supply a dose of tracer-gas without further instructions from the controlling computer. Range of values: 1-3600s, default value: 60s. Dimensions: Height – 175mm, width – 395mm, depth – 300mm, weight – 9kg.

Measuring of air exchange rate (n) using the tracer-gas technique with constant concentration or constant dosage methods. Ventilation measurements and calculations of an air exchange efficiency, age-of-air and other parameters for up to 6 locations in a room. Long-term monitoring of formaldehyde, TOCs, CO2 concentration.