About

A gaseous sampling attachment is a device that attaches to a particulate sampler to collect air pollutants, such as

SO2cap S cap O sub 2

2

and

NO2cap N cap O sub 2

2

, while the particulate sampler collects dust. It lowers the required airflow to a few liters per minute and uses impingers or other methods to absorb gaseous pollutants for analysis. Modern versions often include features like thermoelectric cooling to maintain the optimal temperature for absorption without needing an ice bath.

• Collects gases: Allows for the simultaneous sampling of gaseous pollutants alongside particulate matter.
• Low airflow: Designed for the lower airflow rates (a few LPM) needed for gas sampling, contrasting with the high flow rates of particulate samplers.
• Absorption and cooling: Typically uses impingers to absorb gases. Many advanced models use thermoelectric cooling to maintain an optimal temperature for the absorbing solutions, ensuring efficiency even at high ambient temperatures.
• Constant flow: Features an improved valve design to maintain a constant flow rate throughout the sampling period.
• Moisture and particulate removal: May include filters, such as silica gel tubes, to remove entrained moisture and particulates from the air stream before it reaches the absorption media.
• Versatility: Can be configured with different types of impingers for various specific pollutants (e.g., PTFE impingers for fluorides). Some can sample multiple gases simultaneously.
• Durability: Often built with durable materials and housed in a protective cabinet suitable for outdoor and industrial environments.