Context
- A plastics recycling facility included a wash plant to clean incoming material.
- Caustic soda – sodium hydroxide – was pumped from a bulk container into a vat within the wash plant.
- The area was surrounded by a bund to contain liquid.
- C was a labour hire worker on placement at the facility.
- C had not been briefed on what the liquid in the bund was or what PPE should have been worn while walking in the bund, ie: gumboots.
- He was not wearing footwear that would have protected against alkaline burns.
Detail
- C started his shift at 7.30am and went to the wash plant to see if a bag holding plastic waste need to be changed.
- C entered the bund and found a new bag was needed. C detached the full bag and lowered it onto a trolley.
- C was exposed to liquid in the bund for about three minutes.
- Soon afterwards C felt discomfort in his toes. When the pain worsened he went home.
- C noticed bad blisters on his feet and went to the hospital, which measured a very high alkaline level present.
- C suffered caustic soda burns to the toes on both feet, requiring five skin grafts and eight days in hospital.
- C lost part of the tops of both his little toes.
- A metal grille was later laid over the bund to provide a safe walkway.
Background
- In the hours before C arrived another worker noticed the bulk container was empty and that and that liquid within the bund was white, which was unusual.
- The main hose above the pump had split. The pump was shut down to stop the flow of caustic soda.
- Water was hosed into the bund to dilute the solution that had accumulated.
- The supervisor on the new shift was told about the spill and not to let C change the bags because the bund solution might have been unsafe.
- However, this instruction was not passed on to C.
- The solution in the bund would normally be 2% strength; the solution which caused C’s burns was found to be much higher.
- The design of the bund meant any liquids didn’t drain into a sump but had to be manually pumped out.
Lessons
- Caustic soda causes severe skin burns and eye damage. PPE required includes gloves, protective clothing, eye and face protection, and rubber boots.
- All workers – including labour-hire staff – need to be inducted into their work areas and supplied with appropriate PPE and training.
- Problems encountered in one shift need to be clearly transmitted to the next shift.
- PPE is a last resort. Explore going up the hierarchy of risk controls to minimise or eliminate exposure.
