Mixing of cleaning chemicals

  • Safety Flash
  • Published on 22 July 2022
  • Generated on 22 February 2026
  • IMCA SF 18/22
  • 2 minute read

A worker was exposed to chemical vapours which resulted in breathing discomfort.

What happened?

A worker mixed bleach and toilet cleaner whilst working in the confines of a toilet area onboard a tug. The two chemicals mixed and there was a chemical reaction.  As a result the worker was exposed to chemical vapours which resulted in breathing discomfort. Onboard medical treatment was required, followed by onshore cautionary medical assessment. The worker was diagnosed with Chemical Bronchitis.

What went right?

  • Use of Ship Captains Medical Guide for guidance on treatment onboard.
  • Promptly contacting emergency medical contact for medical advice.
  • Promptly sending the employee for cautionary medical assessment ashore.
  • Full support provided by shore-based management.

What went wrong?

Investigation revealed that the employee involved had no awareness of the consequences of mixing these chemicals.

  • Routine activity without thought.
  • Lack of training, lack of knowledge.
Mixing of cleaning chemicals safety poster

Lessons learned and actions taken in this case

It was realised that the company focus on chemicals awareness was directed more on industrial chemicals with a limited focus on domestic chemicals. Actions were taken:

  • Training materials were provided regarding domestic chemicals.
  • Risk assessments were updated with regard to the mixing of chemicals.
  • There was a review of domestic and industrial chemical stocks, ensuring stock management and seeking to minimise the number of chemicals held onboard.
  • Access to all chemicals (industrial and domestic) should be controlled.

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