The Tube Style 2 mentioned in EPA Method TO-17 is the default configuration of the Air Toxics Tube. From a historical point of view, its functionality combines that of EPA TO- 1 and TO-2. The tube can be used independent of canisters, or in conjunction with.

US EPA Method TO-17: “Determination of volatile organic compounds in ambient air using active sampling onto sorbent tubes” describes a TD-GC/MS based monitoring method for VOC in ambient air at 0.5 to 25 parts per billion (ppbv) concentration levels. The method is based on multi-sorbent tubes carefully selected for the suitable target compounds, and allows some flexibility in tube design to fit individual needs.

Cold trap performance is critical for modern TD-GC/MS instruments. Either working in conjunction with sorbent tubes to form a two-stage thermal desorption system, or by itself similar to the way implemented in PAMS (Photochemical Assessment Monitoring Stations), a cold trap needs to be replaced periodically to ensure repeatability.

This method has been used for the characterization of environments containing mixtures of volatile organic compounds. NIOSH methods are more popular in workplace air quality monitoring, occupational safety and health, and indoor/building air evaluations.

Soil gas/vapor intrusion happens when VOC/SVOC in the air matrix space of soil find their pathway into a buildings, whether residential or commercial. And the measurement of soil gas exposure is an evaluation of potential impact to human health.

The target compounds of SVI study often include, but are not limited to: Polychlorinated Biphenyl (PCB), Polycyclic Aromatic Hydrocarbon (PAH), Diesel Range Organics (DRO), Pesticides, Phthalates, and some Halogenated non-aromatics.

The user can choose Carbosieve™ SIII or Carboxen™ 1000 for their specific analytes or sampling environment. Generally speaking, Carbosieve™ SIII is mostly hydrophobic while Carboxen™ 1000 is significantly hydrophilic.

This tube extends the volatility range of TO-17 Tube Style 2. Choosing Carbosieve™ SIII or Carboxen™ 1000 gives the user some flexibility. This tubes has very low background suitable for trace analysis.

The “Universal” Tube is named this way because it handles the widest range of volatility, and serves as a start point when people don’t know what to expect from unknown air sample.

This Application Note demonstrates the analytical performance of a CDS 7550S thermal desorber coupled to a GCMS for the analysis of TO-17 volatile organic compounds (VOCs) ranging in volatility from Dichlorodifluoromethane to Naphthalene.