49 C.F.R. § 192.490
Each operator that uses direct assessment as defined in §192.903 on an onshore transmission line made primarily of steel or iron to evaluate the effects of a threat in the first column must carry out the direct assessment according to the standard listed in the second column. These standards do not apply to methods associated with direct assessment, such as close interval surveys, voltage gradient surveys, or examination of exposed pipelines, when used separately from the direct assessment process.
| Threat | Standard1 |
| External corrosion | §192.9252 |
| Internal corrosion in pipelines that transport dry gas | §192.927 |
| Stress corrosion cracking | §192.929 |
1For lines not subject to subpart O of this part, the terms "covered segment" and "covered pipeline segment" in §§192.925, 192.927 , and 192.929 refer to the pipeline segment on which direct assessment is performed.
2In §192.925(b), the provision regarding detection of coating damage applies only to pipelines subject to subpart O of this part.
49 C.F.R. §192.490