I've been refueling cylinders here for years. Since I am a private trader, the volumes are small, but there are enough unpleasant little things.
Then the vent is poisoned with 80% of all cylinders, then there is no gas (there is always acid, but the mixture is lucky). It is not always possible to pay by card. According to the mixture, they also cannot tell the ratio of acid and argon. Ordinary employees work normally, refuel properly through the scales.