Ammonia Draining Precautions

Safety bulletin outlining precautions to be observed when draining ammonia from refrigeration plant. 


Ref No



Man Dies Draining Oil



Work Place notice boards together with discussion at your next safety meeting.

In a recent accident a maintenance engineer died during draining oil from an ammonia plant.


There were no witnesses to the accident but it is thought that the engineer began draining the oil then left the plant room, leaving the oil to continue draining. In his absence the flow of oil turned to a flow of ammonia. Then, upon his return to the plant room it is likely that he tried to close the drain valve and in doing so was overcome by the ammonia.


The Coroner blamed the death on the absence of self-closing valves and the engineers lack of experience and training in this type of work.


This accident serves as a stark reminder of the dangers of draining oil on ammonia plants.


To open up an ammonia system including draining oil you must:

•    Be familiar with and work in accordance with the above procedures
•    Be ACRIB registered
•    Have to hand a fully serviceable full-face mask maintained in accordance with safety guidance.
•    Wear goggles and impervious gloves
•    Ensure that safety measures are in place such as adequate ventilation, good lighting, clear escape routes, a supply of water or a drench shower, etc.

Accompaniment is required when:

•    Opening up ammonia systems (including draining oil)
•    You are an apprentice or a trainee (accompaniment must be by ACRIB registered engineer)
•    Respiratory protection needs to be worn or is likely to be worn to carry out the task.
•    Charging or decanting ammonia

The only exception to the accompaniment rule is when all of the following criteria are met:

•    The part to be opened is relatively small.
•    The part to be drained contains only vapour or oil, not liquid ammonia.
•    That part has been isolated so that the amount of vapour that can be released is small.
•    The engineer has had approval from a manager (who is in a position to verify the competence of the individual in relation to the work involved).
•    The oil drain point is fitted with a stop valve and “dead mans handle” valve.


  • If you are routinely and regularly draining oil from a point without a stop valve then dead mans handle – STOP – Report this to your Manager. !


Last modified: Tuesday, 18 February 2014, 12:46 PM