# What does the second laboratory do with the split specimen when it is tested to reconfirm a substituted test result?

- **operation:** document
- **citation:** 49 CFR 40.181
- **title:** What does the second laboratory do with the split specimen when it is tested to reconfirm a substituted test result?
- **source type:** regulation
- **agency:** Pipeline and Hazardous Materials Safety Administration
- **status:** current
- **official:** true
- **published on:** Not available
- **effective on:** 2026-08-18
- **summary:** As the laboratory testing a urine split specimen, you must test the split specimen using the confirmatory tests for creatinine and specific gravity, using the criteria set forth in § 40.88.

[88 FR 27646, May 2, 2023]
- **machine formats:** - **json:** https://regulus.evalyn.ai/document/49-cfr-40-181.json
- **markdown:** https://regulus.evalyn.ai/document/49-cfr-40-181.md
- **app url:** https://regulus.evalyn.ai/document/49-cfr-40-181
- **source url:** https://www.ecfr.gov/on/2026-08-18/title-49/section-40.181
**body:**

As the laboratory testing a urine split specimen, you must test the split specimen using the confirmatory tests for creatinine and specific gravity, using the criteria set forth in § 40.88.

[88 FR 27646, May 2, 2023]
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- **body characters:** 217