[Original text]

飲み水ではありません。（水道の蛇口付近の注意書きとして）
ドアの開閉に注意ください。（電車のドアに貼る注意書きとして）

[Company E machine translation]

It is not a drinking water.
Please note the opening and shutting of the door.

Note: The meaning can be understood somewhat.

[Casual]  Translation fee: 5 JPY x 24 characters = 120 JPY

This is not drinkable water.
Take care not to be injured by the doors.

Note: This is a direct translation, and is very wordy, meaning understanding it takes some time. However, it can be understood well enough. There are no grammatical errors.

[Standard]  Translation fee: 10 JPY x 24 characters = 240 JPY

This is not potable water.
Be careful of the doors.

Note: The meaning can be understood well, and the sentence is concise enough.

[Pro]  Translation fee: 15 JPY x 24 characters = 360 JPY

Do not drink.
Watch your fingers.

Note: Concise expression, avoiding redundancy, which is essential for expressions used in warnings. The translator knows which expression should be used for which occasion.