CFR
- Title 1 - General Provisions
- Title 2 - Grants and Agreements
- Title 3 - The President
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- Title 47 - Telecommunication
- Title 48 - Federal Acquisition Regulations System
- Title 49 - Transportation
- Title 50 - Wildlife and Fisheries
91.415—Raw gaseous sampling procedures.
Fit all heated sampling lines with a heated filter to extract solid particles from the flow of gas required for analysis. The sample line for HC measurement must be heated. The sample line for CO, CO2, and NOX may be heated or unheated.
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