The National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA) recently issued a safety bulletin after it identified three recent incidents where offshore cranes were operated in a reduced lifting capacity (i.e. de-rated) with inadequate controls to prevent overloading.
Upon identification of structural integrity and corrosion defects the cranes had been removed from service.
However, they were subsequently put back into service and operated in de-rated capacity without appropriate management of the hazards associated with defects.
NOPSEMA said offshore cranes are safety-critical equipment as their failure can result in a serious incident.
Globally, the offshore industry has seen many serious incidents involving cranes failing or loads dropped, resulting in the loss of life, damage to equipment, and the release of hydrocarbons with safety and environmental consequences.
The revision of hazard controls, such as de-rating of an offshore crane, is a serious undertaking as the starting point is equipment with compromised controls.
Additionally, the de-rating process is usually conducted under operational pressures potentially leading to consideration of compromised or ineffective controls.
NOPSEMA receives a significant number of notifications of accidents and dangerous occurrences related to cranes and lifting operations.
Crane operations are inherently high-risk operations and any reduction in controls further increases the risk.
The structural integrity and the temporary de-rating of lifting equipment is of concern to NOPSEMA, particularly where the risk to personnel involved in offshore lifting operations are not being properly managed.
NOPSEMA reminded all operators of their legal responsibilities to take all reasonably practicable steps to ensure that any equipment, such as lifting equipment, is safe and does not pose a risk to health and safety.
Additional risk mitigation strategies must be also considered when the lifting capacity of an offshore crane is affected by structural and/or mechanical integrity issues.