Evaluating odor-intensity test results is a critical aspect of ensuring the effectiveness of gas odorization programs. This blog post explores the relationship between percent gas-in-air instrument readings and odor-intensity levels, providing insights into compliance standards outlined in regulations such as 49 CFR §192.625.
High Percent Gas-in-Air Reading: Indicates a weak odor-intensity level, as more gas is required to make the odor perceptible.
Low Percent Gas-in-Air Reading: Indicates a strong odor-intensity level, as the odor is perceptible with less gas flow through the apparatus.
Compliance Standards:
The odor-intensity level is deemed compliant if the Readily Detectable Level (RDL) percent gas-in-air reading is below the limit specified in 49 CFR §192.625 or other applicable regulations documented in the pipeline operator's Operations and Maintenance (O&M) Manual.
Out-of-Compliance Scenarios:
If the RDL exceeds regulatory or corporate limits, the odor-intensity level is considered too weak and is out of compliance.
Potential Causes:
Under-odorization.
Odor fade.
Odor masking.
Insensitive or anosmic tester.
Low RDL Readings and Over-Odorization:
A very low RDL instrument reading with a strong odor-intensity level may indicate high odorant injection rates.
While this can be a safer condition, over-odorization can lead to increased customer leak calls and public concern about gas leak emergencies.
Understanding the nuances of odor-intensity test results is vital for gas distribution operators. By deciphering the relationship between instrument readings and odor-intensity levels, operators can ensure compliance with regulations, promptly address under-odorization or over-odorization, and maintain a robust odorization program for the safety of communities and the reliability of gas distribution systems.