Value | Category |
---|---|
1 | boiling |
2 | boiling chlorination |
3 | boiling chlorination filter |
4 | boiling filter |
5 | boiling safe |
6 | chlorination |
7 | chlorination filter |
8 | chlorination filter none |
9 | chlorination none |
10 | chlorination safe |
11 | filter |
12 | none |
13 | other |
14 | safe |
15 | safe none |
Missing value |