RAM NO2 Technical Data Sheet

Technical Data Sheet: TDS 15 DIFRAM100: RAPID AIR MONITOR - NITROGEN DIOXIDE (NO2). Description: A plastic (H.D.P.E.) circular diffusive sampler containing a sorbent for measuring gaseous Nitrogen dioxide 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 Nitrite ions and hence NO2 chemically adsorbed are quantitatively determined by U.V. / Visible Spectrophotometry with reference to a calibration curve derived from the analysis of standard nitrite solutions (ISO Accredited Methods). RAM Dimensions: 44mm diameter, 18mm height, 28mm sampling surface diameter. Absorbent: 20% Triethanolamine in De-Ionized Water. Recommended Exposure Periods: 1 hour (high concentration areas) to 1-week (time-weighted average studies). Uptake Rate: 28.6 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. Nominal Uptake Rate up to 4 weeks sampling: 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: Approx. 13%. Back Diffusion: No evidence of back diffusion after 48 hours. Storage: Store in a dark, cool environment preferably between 5-10 °C. Shelf Life: 6 months when stored in accordance with published storage instructions. Limit of detection: Less than 0.2 ugm-3 over a 1 week exposure period. Specific values available upon request. Expanded Relative Measurement Uncertainty at 40ugm-3 limit value: +/-13. 0%. Expanded Measurement Uncertainty based on laboratory validation tests: +/-24.8%. Desorption Efficiency: d = 0.99 (determined using N.I.S.T. Standard Analytes). Relevant Standards: The sampler has been validated for compliance to European Standard EN 13528-2: 2008 by an independent accredited laboratory. Special Factors: Potential interference from Nitrous Acid, Peroxy Acetyl Nitrate, which could increase levels of nitrate. TDS 15:V1 March 2012