A concrete pump truck was pumping concrete into the walkway of a house while a worker held the end hose.
The rubber hose was 20 feet (6 metres) long and had a coupling device attached at the end. The operator
of the concrete pump truck saw that the concrete had stopped flowing out of the hose as the result of a
blockage. He pushed the emergency stop button and the pumping stopped. However, compressed air trapped
behind the blockage forced it to clear suddenly. Concrete burst out of the hose, causing the hose to whip out.
The worker holding the hose fell backwards. He struck his head on a piece of scrap lumber and later died of
his injuries.
Safe work practices: 
- Train workers to prevent blockages in
pumping delivery pipelines and to
recognize the warning signs of blockages
with trapped air behind them.
- Establish and enforce safe work
procedures for concrete pumping
operations, including the following:
- Maintain regular communication
between workers about hazards
while the pumping operation is
in progress.
- Stay out of the end-hose
discharge area when air has
entered the delivery system
and a blockage is suspected.
- Follow the manufacturer's
instructions for the operation
and maintenance of concrete pump
trucks. For example, the end hose
should be no longer than the
manufacturer allows, and it should
not have a coupling attached at the end.
