Cranes and Site Safety Precautions

Introduction

A crane is not just a machine that lifts weight. It is a full lifting system that includes ground conditions, outriggers, rigging gear, load weight, wind, the rigger, signalman, and swing path. A small error in lifting angle or ground stability can turn a simple lift into a serious accident.

Choosing the crane

For light and medium city lifts, a 25–55 ton truck crane may be enough, such as SANY STC250T5 with 25 ton capacity and a 41 m boom [S7], or similar Zoomlion/XCMG models. Rough or oilfield sites may need a rough-terrain crane such as Tadano GR-800EX with 80 ton capacity and up to 64.4 m lifting height [S6]. The rated capacity is not available at every radius; the load chart is the real rule.

Ground and outriggers

OSHA defines ground conditions as the ability of the ground to support the equipment, including slope, compaction, and firmness, and requires ground to be firm, drained, and graded to meet manufacturer requirements [S4]. In Kuwait, recent backfill, sandy areas, and utility sites require extra attention to outrigger mats and leveling.

Lift plan

A proper lift plan includes load weight, center of gravity, radius, lift height, swing route, rigging type, rigging certificates, wind condition, exclusion zone, and emergency plan. Operator experience is important, but it does not replace calculation.

Indicative chart for explanation and analysis only.

Practical points

• Do not operate a crane without the load chart available to the operator and supervisor.
• Check ground bearing pressure before heavy lifting.
• Barricade the swing area and never allow people under a suspended load.
• Reject any lift where the load weight is unknown.