Incident - Skin grafts from chemical burns

A labour hire worker required skin grafts after coming into contact with a highly alkaline caustic soda solution while carrying out a routine task without appropriate PPE. PETER BATEMAN summarises.

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.