While tripping drill pipe out of hole the Derrickman’s Fall Arrestor line got entangled on the traveling
block as it was being lowered. Abrupt tension on the fall arrestor line caused Derrickman, who was
racking a drillpipe stand, to fall on monkey board. The fall arrestor line then snapped in tension &
caused a 7cm cut on the left side of IP’s neck. Additionally, drill collar locking chain hook on
monkey board finger caused severe injury to his throat. IP was evacuated from monkey board,
stabilised at PDO Nimr Clinic & then transferred to Salalah hospital.
• Improper Derrick man Fall Arrestor rig up – slack in restraining line caused interference of fall
arrestor line with moving Traveling Block or its components
• Not fit for purpose chain hooks ( sharp edges).
• Ensure Fall Arrestor line always remains clear of moving travelling block and winch lines.
• Clearance between Travelling Block and Fall Arrestor to be checked prior to starting any job on
monkey board.
Recommended Actions:
• Discuss this alert in toolbox talks and HSE meetings and
 Distribute to all contractors
 Post on HSE notice boards
 Include in site HSE induction
Always check clearance between moving Travelling Block
and all lines in mast before working on Monkey Board
Contact MSE511 for further information or visit HSE website
Reference: LTI No. 32
Alert No. 10
August 2010