Skip to content

Oil tank sight glass push buttons wired open

What happened

On a visit to an engine room, a serious bypassing of safety controls was observed. Both top and bottom level check push buttons on an Oil Tank Sight Glass were inhibited by wire. The sight glass is used to check the oil level in storage tanks. It is designed such that a button has to be pushed to check and verify the level of the oil tank.  The button allows a connection between the sight glass and the oil tank. Whilst the button was wired open, if the glass tube were to be accidentally broken or damaged, then the contents of the tank could easily spill into the engine room with consequent further serious hazard of slips/trips, fire, and lack of oil where it was intended.

Top of sight closing device blocked by wire
Bottom of sight closing device blocked by wire

What was the cause?

  • Unsafe behaviour – this was an intentional override of a design feature related to safety-critical equipment
    • The oil level gauge closing device had been inhibited with wire and remained in open position for a long time.

Members may wish to refer to

Safety Event

Published: 13 December 2022
Download: IMCA SF 28/22

Relevant life-saving rules:
IMCA Safety Flashes
Submit a Report

IMCA Safety Flashes summarise key safety matters and incidents, allowing lessons to be more easily learnt for the benefit of all. The effectiveness of the IMCA Safety Flash system depends on Members sharing information and so avoiding repeat incidents. Please consider adding [email protected] to your internal distribution list for safety alerts or manually submitting information on incidents you consider may be relevant. All information is anonymised or sanitised, as appropriate.

IMCA’s store terms and conditions (https://www.imca-int.com/legal-notices/terms/) apply to all downloads from IMCA’s website, including this document.

IMCA makes every effort to ensure the accuracy and reliability of the data contained in the documents it publishes, but IMCA shall not be liable for any guidance and/or recommendation and/or statement herein contained. The information contained in this document does not fulfil or replace any individual’s or Member's legal, regulatory or other duties or obligations in respect of their operations. Individuals and Members remain solely responsible for the safe, lawful and proper conduct of their operations.