Table 4.
Sample sources | Sample size | Collection date | Test date | Test items | Test methods | Test results | Reference values* |
---|---|---|---|---|---|---|---|
Water well | 1 | 5 Feb. 2015 | 5 Feb. 2015 | Total bacteria count | Plate count method | 710 c.f.u./ml | ⩽100 c.f.u./ml |
The coliform group | Lactose fermentation, separate cultivation and confirmatory test | 1600 c.f.u./100 ml | Negative | ||||
Thermotolerant coliform bacteria | Membrane filter technique | 1600 c.f.u./100 ml | Negative | ||||
Water boiler | 1 | 5 Feb. 2015 | 5 Feb. 2015 | Total bacteria count | Plate count method | Negative | ⩽100 c.f.u./ml |
The coliform group | Lactose fermentation, separate cultivation and confirmatory test | Negative | Negative | ||||
Thermotolerant coliform bacteria | Membrane filter technique | Negative | Negative | ||||
Tap-water pipes† | 8 | 8 Feb. 2015 | 8 Feb. 2015 | Total bacteria count | Plate count method | 0–3 c.f.u./ml | ⩽100 c.f.u./ml |
The coliform group | Lactose fermentation, separate cultivation and confirmatory test | Negative | Negative | ||||
Thermotolerant coliform bacteria | Membrane filter technique | Negative | Negative | ||||
HEV | Real-time PCR | Negative | Negative |
The reference values were derived from standards for drinking water quality issued by the Ministry of Health of China.
The water samples were collected from four different tap-water pipes. Of these, three were located in the rooms of different cases, while one was located in the refectory of the nursing home. Two samples were collected from each tap-water pipe.