How is each SAMM connected to the sample area?

• A. By flexible silicone tubing
• B. By copper tubing
• C. By Polyvinyl chloride tubing
• D. By Semi-rigid Polyethylene Tubing (Freeways)

Answer: (D)

The line from the SAMM to the sample area must preserve the sample as it moves to the analyzer, with minimal loss or contamination of gases like H2S and hydrocarbons. Semi-rigid polyethylene tubing fits this need best because it stays open and resists kinking, making routing easier in field setups. It also has excellent chemical compatibility and low permeability, so the sample isn’t absorbed or exchanged with the tubing material as it travels, which keeps measurements accurate. Other materials tend to introduce problems: flexible silicone can sorb or swell with organics and gases; copper can react with sulfur species and is less practical for flexible, long runs; PVC can permeate or become brittle under varying temperatures. Using semi-rigid polyethylene tubing (often referred to in SAMM setups as Freeways) provides reliable, field-friendly sample transfer with the least risk of altering the sample before analysis.