| Clue | Source | Date |
|---|---|---|
| Invisible danger | Wall Street Journal | 04 May 2024 |
| Unseen danger | Wall Street Journal | 28 Aug 2021 |
| What a home alarm might signal | Newsday | 16 Mar 2019 |
| Seepage of methane, e.g | Premier Sunday | 17 Dec 2017 |
| It may lead to an explosion | The Washington Post Sunday | 12 Nov 2017 |
| Serious pipe problem | ||
| Dangerous pipe problem | ||
| Dangerous pipe problem |