Safety alert 18 - Dropped tongs video transcript
This video safety alert has been produced by NOPSA (National Offshore Petroleum Safety Authority) to share information from an incident investigation. This alert is about a very simple and routine lifting operation and whilst not identifying all of the factors involved, it strives to illustrate how dangerous routine lifting operations can be as it almost killed a man.
Planned lifting operation
The day of the incident the crew had attended a pre-tower safety meeting, and discussed the day’s planned activities including general deck operations. The need for the tongs hadn’t been identified at the start of the shift, but the movement of equipment to the rig floor is very common and should be done safely using routine task-level assessments and following standard procedures.
Two three and a half inch pipe tongs, weighing 110 kilograms each were being lifted to the rig floor when the load got snagged, the sling failed and the tongs fell approximately 5 metres.
We will go through the lifting operation step-by-step and review the barriers that should have prevented this.
Experience of the team
The experience of the deck crew in these positions that day was:
Roustabout (who was injured) – 18 months
Dogman – approximately 120 days
Crane Operator – 6 days; as we’ll explain he was working under supervision.
Load ready to be lifted
The deck crew were asked to move the tongs from the store, which is located on the starboard side below the elevated catwalk, up to the rig floor. The crew had been working for about 3 hours in hot but not bad or unusual conditions.
The Crane Operator came to help the roustabout get the tongs out of the store and positioned for the lift. The supervising crane operator had gone for a break. The dogman had been working elsewhere, but arrived at the site in time to review the slings and take charge of the lift.
The crane operator went to the crane to start the lift.
The dogman signalled the Crane Operator to start the lift, and then moved up the stairs towards the rig floor, pausing to clear people on the catwalk.
The roustabout went back into the store to replace an unused sling.
Now the problems begin:- the Crane Operator is working unsupervised, the dogman has not stood to one side to oversee the lift, and there is no clear agreement on who should be where during the lift.
Roustabout starts up the stairs
The Roustabout moves up the stairs to help strap pipe on the catwalk; it is not clear if any one saw him entering the danger zone, but clearly neither the Dogman or the Crane Operator realised what he was doing. By not looking up, the Roustabout had put himself in serious danger; this sort of exposure can happen very easily and quickly.
Load hooks-up on handrail
As the crane operator was moving the load towards the rig floor, he noticed the load starting to swing. He attempted to chase the load by moving the boom towards the rig floor and the load snagged on a hand rail.
Sling breaks, load falls
The crane operator was continuing to come up on the load, and the roustabout was continuing to come up the stairs. The sling parted under the additional strain of being pulled between the crane and the snagged load.
The sling parted.
Final resting place of tongs
The tongs fell, luckily one on either side of the roustabout. The lower one fell to the bottom of the stairs, the one that fell above the roustabout fell down the stairs and knocked the roustabout from his feet.
Failure of controls
This routine operation was carried out in daylight by a relatively experienced crew. A number of significant controls failed to protect the roustabout; such as
The level of supervision
Task level planning and risk assessment.
Knowledge and use of the safety management system
Experience of the personnel involved
Safety management systems are designed to avoid the need to rely on the less effective controls; PPE would have been of no use here, but the administrative and procedural controls are also relatively weak. That is why it is important to ensure they are working effectively. This reduces the number of gaps in the defences and should ensure safe and consistent operations offshore – avoiding the potential fatalities still happening offshore today.
Dropped objects calculator
In closing let’s have a quick check, in case you are in any doubt, about what could so easily have happened.
This chart shows the combinations of height and mass (or weight) that are likely to kill you when a dropped object falls on you.
From a height of four metres, a weight as small as three kilos can be fatal. In this case we are talking about two objects, each weighing 110 kilograms.
For more information on NOPSA please visit our website.