Part 2-1 General sets out the principles of inspection, maintenance and through examination of all types of cranes, whilst the subsequent sub-parts detail the particular requirements for specific types of crane. Compared with the previous edition of Part 2, there is a major emphasis on the importance of planned preventive maintenance, especially for those cranes where failure may have catastrophic consequences for workers and members of the public. Part 2-1 also deals with the selection, training and assessment of personnel carrying out inspection, maintenance and through examination.

Part 2-5, which covers the requirements for tower cranes, says that regular pre-use checking, in-service inspection, maintenance and thorough examination of cranes are essential if cranes are to function safely and reliably. The nature of these activities can be summarized as follows.

  • Pre-use checks are visual checks which are carried out to ensure that the crane has not suffered any damage or failure, and is safe to use;
  • In-service inspections and maintenance are carried out to ensure that components are repaired or replaced before they deteriorate to a point at which they would become unsafe;
  • Thorough examinations are carried out at specified intervals, after installation on a new site, after major alteration or repair or after the occurrence of exceptional circumstances which could jeopardize the safety of the crane;
  • Supplementary testing is carried out in support of thorough examination and the extent and nature of any testing are specified by the competent person carrying out the thorough examination.

The requirements for each of these activities are described in detail for tower cranes and emphasise the importance of effective records. These records should demonstrate that the various activities have been carried out, ensure that people are aware of what has been done and enable reviews of the process to be carried out to ensure that it is both effective and efficient. The standard advocates setting up machine history files for each tower crane, one kept by the owner and the other on the site on which it is currently erected. The owners file will contain all records of inspection and maintenance from the time the crane was purchased, whilst the site file will only contain copies of records for the period that the crane is on site. Non-exhaustive lists of the records for both types of machine history file are included in the standard.

Requirements for the thorough examination of tower cranes include — the types of thorough examination, scope of thorough examination and the components to be included, assessment criteria, thorough examination intervals, preparation for thorough examination and thorough examination records. These requirements supplement the general requirements for the thorough examination of cranes set out in BS 7121- 2-1 General.

The final part of the standard covers tests to supplement thorough examination. These are overload testing, non-destructive testing and RCI/RL tests.

The document also has seven annexes which give examples of:

  • checklists for pre-checks and inspections during maintenance;
  • reports for base pre-erection inspections and tower crane tie pre installation inspections;
  • certificates for base approval/completion and tie approval /completion;
  • procedures for thorough examination and supplementary testing of climbing frames.

For the effective inspection, maintenance and thorough examination of tower cranes, owners and users will need copies of both BS 7212-2-1:2012 and BS 7212-2-5 which can be obtained from BSI at http://shop.bsigroup.com/. This revision of BS 7121 part 2 offers critical guidance to all users and operators of cranes throughout the UK and also has worldwide applicability.

Understanding BS 7121
The British Standards Institution (BSI), the national standards body for the UK, has recently revised Part 2 of BS 7121, Code of practice for safe use of cranes. Part 2 deals with inspection, maintenance and through examination of cranes and has been split into six sub-parts, to bring more focus on specific types of crane. The first four parts, published in November 2012, were:-

  • BS 7121-2-1 Code of practice for the safe use of cranes – Part 2-1:Inspection, maintenance and thorough examination – General;
  • BS 7121-2-3 Code of practice for the safe use of cranes – Part 2-3: Inspection, maintenance and through examination – Mobile cranes;
  • BS 7121-2-5 Code of practice for the safe use of cranes – Part 2-5: Inspection, maintenance and through examination – Tower cranes;
  • BS 7121-2-7 Code of practice for the safe use of cranes – Part 2-7: Inspection, maintenance and thorough examination – Overhead travelling cranes, including portal and semi-portal cranes, hoists, and their supporting structures.

Two more parts, BS 7121-2-4 Loader cranes and BS 7121-2-9 Cargo handling and container cranes, will be published later this year.

Planned preventive maintenance checklist
Planned preventive maintenance of tower cranes is covered with a set of comprehensive requirements including:-

  • Pre-delivery inspection and maintenance of the crane and its components to ensure that any issues are identified and rectified before the crane arrives on site for erection;
  • Post-delivery checks on site to ensure that any damage during transport is identified and rectified before erection of the crane starts, as it is always easier and safer to carry out work on the ground rather than at height;
  • Pre-erection checking and inspection of the base and any ties to ensure that the design, construction and installation are check to ensure that they will take the loads imposed on them;
  • Checking of mast verticality;
  • Setting of the in-service maintenance intervals to take account of usage, environment and abnormal wear patterns;
  • Ensuring that maintenance personnel have access to adequate information to enable them to carry out their duties safely and effectively;
  • Inspection during maintenance to identify defects and ensure they are rectified. The standards says that "When inspections are being carried out as part of maintenance it is important that maintenance personnel record all faults and do not omit to record faults that are then rectified as part of the maintenance process. Such masking of faults would invalidate the machine history and hinder the review process."
  • Allocation of adequate time for maintenance. The standards warns that "It is essential that maintenance downtime is scheduled into the work programme, so that maintenance is not pushed to the back of the queue and does not end up being carried out hurriedly in unsafe conditions such as poor light."
  • Management review of maintenance records and procedures to enable them to be confident that a robust maintenance system is in place that can be relied upon to rapidly highlight any shortcomings and the need for corrective action;
  • Effective lines of communication between those planning and carrying out maintenance on tower cranes and site staff for both routine maintenance and attending to breakdowns;
  • Ensuring that spare parts are available and that if they are not supplied by the crane manufacturer that they meet the original manufacturer’s specification.