Causes of overturning of boom mobile cranes and their consequences

Operation of boom-type self-propelled cranes is associated with the risk of crane overturning. According to statistics, 50% of incidents involving boom-type self-propelled cranes are caused by crane overturning.

Lifting and moving loads by several cranes simultaneously presents particular complexity and significant danger.

Extract from the Rules for Ensuring Industrial Safety of Lifting Cranes, approved by the Resolution of the Ministry of Emergency Situations of the Republic of Belarus of December 22, 2021 No. 66 (hereinafter referred to as the Rules):

330. A boom-type self-propelled crane shall be installed on a site planned and prepared in accordance with the work execution project (technological documentation), taking into account the category and nature of the soil. It is prohibited to install a lifting crane for operation on freshly dumped, untamped soil, on a concrete foundation whose reliability has not been verified, on manhole covers or utilities, as well as on a site with a slope exceeding that specified in the passport.

This year, Gospromnadzor received information about four incidents related to loss of stability and subsequent overturning of boom-type self-propelled cranes installed on automotive chassis.

I. On March 17, 2025, an automotive crane KS-6572SZ overturned at a construction site in Grodno. As a result of the overturning, the crane was damaged. There were no casualties.

Based on the results of the technical investigation into the causes of the incident related to the technical condition of the automotive crane, no issues were identified, but violations of industrial safety legislation were committed.

The boom-type self-propelled crane was installed on an unplanned and unprepared site without considering the category and nature of the soil; strong and stable supports were not placed under the outriggers.

The work execution project does not specify the installation locations of lifting cranes for construction and installation, loading and unloading operations at the site (clauses 332, 334 of the Rules).

The work was carried out in the absence of a person responsible for the safe operation of lifting cranes and riggers at the site.

II. On June 19, 2025, the State Industrial Supervision received information about a fatal accident involving a carpenter-concreter of SU-95 of OAO Stroyтрест № 3 of the Order of the October Revolution.

The accident occurred at a construction site in the Slutsk district when a KTA-28 truck crane was moving a concrete bucket at a height of about 4 m for pouring a monolithic belt of the building under construction. During this operation, the truck crane with the moved bucket lost stability and tilted towards the building under construction, with the subsequent resting of the truck crane boom on the scaffolding.

As a result, a carpenter-concreter, who was on the scaffolding at that time, was fatally injured (pinned to the scaffolding) by the crane boom.

It was established that there are no technical reasons for the accident related to the technical condition of the lifting crane.

III. On September 11, 2025, at the facility "Construction of a military town in the Gomel region. Military town, Phase I of construction," a mobile crane КС-55727-А overturned while a loader bucket (weighing approximately 0.9 tons) was being moved. The crane was damaged as a result of the overturning. There were no casualties.

Violations of industrial safety legislation requirements:

- Installation of the lifting crane on an unprepared site on freshly filled and untamped soil,

- Production of work by the lifting crane was not suspended (prohibited) in the absence of requirements for the installation of the lifting crane in the work project.

IV. On September 26, 2025, on the territory of LLC "KimaBel" (Polotsk district, village Bogatyrevka), a SANI STC 750 mobile crane overturned while loading a container (weighing about 30 tons) onto a railway platform. There were no casualties. The lifting crane was damaged as a result of the incident.

The investigation is not complete.

To prevent similar incidents, owners of mobile cranes and entities performing work using lifting cranes must ensure the implementation of the following measures:

- Substantive (not formal) implementation of industrial safety production control during the operation of lifting cranes (Clause 336 of the Rules);

- Appointment of persons responsible for the safe execution of work by lifting cranes after their training and knowledge testing on industrial safety issues (Clause 337 of the Rules);

- organization of the development of instructions for persons responsible for safe operation, and instructions for safe work practices (operating instructions) for workers employed as crane operators and riggers (Clause 338 of the Rules);

- conducting briefings for crane operators (crane drivers) and riggers on the safe performance of upcoming work, paying attention to hazardous factors,

- special conditions at the work site, prevention of overloading of lifting cranes, correct slinging and hooking of loads, correct positioning of mobile boom cranes, correct performance of work during loading and unloading of gondola cars, platforms, and vehicles, compliance by riggers with safety requirements (Clause 405 of the Rules);

- direct supervision of work during loading and unloading of gondola cars, during movement of loads by multiple lifting cranes, near power lines, during movement of loads over ceilings under which production or service premises are located where people may be present, during movement of loads for which no slinging diagrams have been developed, as well as in other cases provided for by projects or technological regulations (Clause 405 of the Rules);

- instructing crane operators (crane drivers) on the placement of mobile boom cranes and entering a record of the decision to perform work in the duty log (Clause 405 of the Rules);

- prohibiting work without a work permit in cases provided for by the Rules, work design, and technological regulations (Clause 405 of the Rules);

- development and issuance to work sites of construction and installation work designs using lifting cranes, technological charts for storage of loads, loading and unloading of vehicles and rolling stock, and other technological regulations (Clause 419 of the Rules);

- familiarization (under signature) with projects and other technological regulations of persons responsible for the safe operation of lifting cranes, crane operators, and slingers (Clause 419 of the Rules);

- provision of slingers with a high-visibility vest for nighttime, personal protective equipment (standard safety helmet), tested and marked removable lifting devices and containers corresponding to the weight and nature of the loads being moved (Clause 419 of the Rules).