Mixing of cleaning chemicals

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.

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.

Members may wish to refer to:

• Chemical reaction: person injured during grouting operations [water mixed with grouting dust to make a corrosive solution. The consequence of this mixing was not clear in the Safety Data Sheet]
• HSE: Allergic reaction at work [a company failed to carry out a suitable and sufficient risk assessment to identify the potential for exposure to the hazardous chemicals]
• Inhalation of toxic fumes during hot work [There was a lack of awareness of chemicals being used]