Hot and cold water dispensers are virtually ubiquitous in the office - and increasingly at home. Are these dispensers as hygienic as they are convenient in the delivery of drinking water?
To assess the extent of the potential problem, the Consumer Council has conducted a small-scale test on a number of water samples collected from the dispensers on its office premises.
The water samples, much to the relief of its staff, scored a clean bill of health. No E. coli was detected in the drinking water - though not without a Total Bacterial Count (TBC) of 16 cfu/ml to 1,100 cfu/ml. As bacteria in water dispenser are generally non-pathogenic, they are unlikely to cause disease. Nonetheless, the bacteria may multiply very rapidly to a large number over time, which may pose a potential health problem to people if their body immune system is compromised.
A report published by the China Consumer Association in 2001 indicated that water samples of satisfactory bacteriological quality became immediately contaminated on the very day the water was attached to dispensers that had not been disinfected, rising to 100 cfu/ml to 370 cfu/ml. On the third day, the TBC had escalated rapidly to 10,000 cfu/ml to 150,000 cfu/ml.
The bacteriological quality of carboy water depends on two levels - first, the water itself and, second, the dispenser through which the drinking water is delivered. So, if the dispenser is not maintained in good hygienic condition, the water gets contaminated, a phenomenon called "secondary contamination".
Clearly, one way to minimise the problem of contamination of water dispenser is by proper and regular cleaning and disinfection.
To assist consumers, the Council has conducted a market survey on the cleaning and disinfection services provided by nine water dispenser agents:
- For a fee, all agents will in fact offer cleaning and disinfection service ranging from $80 to $690 per job, depending on the dispenser model, on-site or off-site service, extent of disinfection, etc.
- But only some (3 out of 9) agents will provide it during the free warranty period; and on expiration of the warranty period, some (4 out of 9) agents will provide maintenance service that includes cleaning and disinfection.
Consumers are advised to take heed of the importance of good hygiene practice and proper use and maintenance of water dispensers to minimise the chance of contamination.
This includes locating the dispenser indoors in a clean, cool, dry, well-ventilated space, and away from direct sunlight.
When placing the water, wash hands, wipe the neck of the bottle with clean tissue paper, do not touch the opening of the bottle. Equally important, do not touch the end of the water dispenser spigots with hands or other objects.
It is also recommended that the water, once placed on a dispenser, be finished within three to five days. Therefore, depending on the usage frequency, small family will do well to choose water of smaller volume for its dispenser.
In addition, the Council has also surveyed the prices of nine brands of carboy water, covering the original price per bottle and the discount price of a total of 42 packages (exclusive of water dispensers):
- Based on their original price per bottle, the price variations of carboy water (which comes in three kinds, namely, distilled water, water with minerals, reverse osmosis purified water) are substantial, ranging from $17 to $51 for the smaller size (around 11.3 litres), and $20 to $81 for the bigger size (around 18.9 litres).
- Even based on their package price, the difference, in the case of distilled water, can be as much as three times - from $1.1 to $4.2 per litre.
- On the whole, packages offer benefits in the form of price discount. But do not be easily tempted by the lower unit price; bear in mind that space is needed to store the used and new water bottles and overdue coupons may not be redeemable.
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