The 29 companies joining the campaign, initiated by the Chamber of Commerce and Industry's (GZS) public utilities division, received a special certificate today.

They committed to providing only tap water in glass jugs and glasses at their offices and business events, encouraging their employees and partners to drink tap water more and raising the awareness about the quality of drinking water in Slovenia.

The first to join the campaign were the Environment Ministry and the Health Ministry at the start of the year.

"Slovenians are not informed enough about the quality of drinking water, having almost unlimited amounts of it. Considering that we have enough clean water, we also need to feel responsible to protect the country's water sources," said the head of the GZS' public utilities division, Sebastijan Zupanc.

Commercialisation has led to stores selling bottled water, which is not as fresh as tap water and of lower quality. Bottled water is often also not stored properly and is exposed to heat or the sun, he said.

Among today's recipients of the tap water campaign certificate is the Slovenske Konjice public utility, which donated glass bottles for tap water to all its employees a few years ago.

The company noticed that by encouraging its employees to drink more water and eat more locally-produced vegetables, it has reduced the number of work days lost to sick leave.