201779 No gloves would have been better

While at sea, an engine room crew member began work using the ship’s drill press and a securing vice. He was drilling 18mm holes into stainless steel plates of about 2-3mm thickness, wearing his usual personal protective equipment (PPE), including cotton gloves. The hole was drilled without incident, but when the drill bit was retracted, it jammed in the plate hole. Under the rotational force of the spinning drill bit, the plate came out of the vice and spun with the drill bit. The spinning plate caught the operator’s left hand, which was on the vicehandle.

The operator quickly stepped on the ‘stop control’ foot pedal, but the momentum of the plate was high enough that the drill did not stop immediately. The victim was treated as far as possible on board and then evacuated to a shore hospital. Unfortunately, the severity of his injuries – complete removal of skin and muscle tissue down to the bone of the left index finger – required the amputation of the finger.

 

The investigation found that the cotton gloves worn by the victim probably aggravated his injuries. The company had issued a safety circular several years earlier prohibiting the use of gloves when working on the lathe and drill machines. However, this information was not displayed near these tools, nor had the victim received this information in any other way.

 

The investigation also determined that there was a high probability the drill bit would jam in the hole, because of the size of the drill bit compared with the thickness of the plates. Clamping the plate in the vice without other support is not good practice.

 

Lessons learned

- A ‘dead man’s switch’ is safer than an independent emergency stop switch. A dead man’s switch needs to be continually depressed to keep the machine operating.

- Under certain circumstances some kinds of PPE (such as cotton gloves in this instance) are actually counter-productive. Proper training and information placards can help inform crew what to wear and when.