Ammonia RAM Technical Data Sheet

Technical Data Sheet: TDS 18 DIFRAM400: RAPID AIR MONITOR – Ammonia, NH3 Description: A plastic (H.D.P.E.) circular diffusive sampler containing a sorbent for measuring gaseous Ammonia in ambient air. This sampler is designed to provide a considerably higher uptake rate than the passive axial diffusion tube, which allows a higher flexibility of ambient air pollution measuring in outdoor and indoor environments. It can equally effectively be used as a personal sampler for health and safety monitoring in workplace and public/social environments. It is recommended that one sampler is used as a blank for each batch of samplers ordered. The concentrations of Ammonium ions and hence NH3 chemically adsorbed are quantitatively determined by Ion Chromatography with reference to a calibration curve derived from the analysis of standard ammonium solutions. RAM Dimensions: 44mm diameter, 18mm height, 28mm sampling surface diameter. Recommended Exposure Periods: 1 hour (high concentration areas) to 4-weeks (time-weighted average studies). Nominal Uptake Rate: 47.0 ml/min at 20 °C. Air Velocity: 0.2 to 0.7m/s: No statistical significance at 95% confidence levels. Orientation (Normal / Perpendicular): No statistical significance. Temperature Range: –5 °C to 30 °C: Increase in uptake rates at higher temperature: Temperature correction to be applied in calculation. If the average temperature is not provided, the results will be corrected to 20°C. Relative Humidity: 20 to 70%: Slight increase in uptake rate at higher humidity: Back Diffusion: No evidence of back diffusion after 168 hours. Storage: Store in a dark, cool environment preferably between 5-10 °C. Effects of storage: 2% difference in uptake rate after 2 weeks storage. (Laboratory validation) Shelf Life: 8 weeks when stored in accordance with published storage instructions. Limit of detection: Less than 2.0ugm-3 over a 2 week exposure period. Specific values available upon request. Expanded Relative Measurement Uncertainty at 25ugm-3 limit value: +/-18.8%. Exposure Measurement of Uncertainty based on laboratory validation tests: +/-18.8%. Desorption Efficiency: d = 0.99 (determined using N.I.S.T. Standard Analytes). Reproducibility: 9.3% (average relative standard deviation) TDS18 Ver1 April 2013 Relevant Standards: The sampler has been validated for compliance to European Standard EN 13528-2: 2002 by an independent accredited laboratory. Special Factors: Potential interference from aerosol particles containing high levels of ammonium i.e. fertilizers. TDS18 Ver1 April 2013