Particular care should be taken with the following substances:
- Pyridine. Pyridine is poisonous but no danger to health should arise provided that the normal rules of hygiene are observed. Any sample of pyridine required should be drawn by the producer in your presence;
- Methyl violet. Direct contact of methyl violet with the hands is to be avoided and you should be particularly careful to prevent the introduction of methyl violet into cuts or broken skin;
- Pure methyl alcohol. Prolonged exposure to the vapour from methyl alcohol can be dangerous. Sampling must be carried out in a well ventilated place, and care must be taken to avoid the liquid coming into contact with the skin.