Safe use of tower cranes

In response to the comments made by the Chamber of Engineers, the Occupational Health and Safety Authority would like to point out that a code of practice - Code of Practice for the Building and Construction Industry in Malta - issued way back in 1997 clearly outlines all the points raised in their statement.

The scope of the code is to provide practical guidance on a technical, administrative and legal framework for health and safety in the construction industry, to ensure a better level of protection of the health and safety of workers and to prevent harmful effects on the health of workers and accidents arising from employment in the construction industry.

Although failure to comply with any provision of this code is not of itself an offence under Act VII of 1994 (which has now been replaced by Act XXVII of 2000), this latter Act clearly states that it is the duty of the employer to ensure the safety and health of all the workers who are carrying out work for that employer, as well as of third parties. It states further that the measures taken by employers to prevent physical and psychological occupational ill-health, injury or death, should be taken on the basis of a list of prescribed general principles of prevention, including "the taking of all the necessary measures to reduce risk as much as reasonably practicable, including the replacement of the hazardous by the non-hazardous or by the less hazardous".

In the case of the building and construction industry, what is deemed as reasonably practicable is enshrined in the code of practice.

Thus, the non-implementation of any of the provisions of the code of practice is justifiable solely on the grounds that the employer is taking measures which offer a higher level of protection for the health and safety of the employees. One must not overlook the fact that employers are also duty bound by law to carry out and update a risk assessment.

A risk assessment is basically a careful evaluation of all those factors that could injure or harm people so that the employer can determine whether enough precautions have been taken and what else should be done to improve the situation.

The 1997 code of practice has clear procedures to be followed when undertaking works and services in the construction industry. These also include a section outlining in detail the general duties of employers, project supervisors and coordinators and employees.

There is also a specific section covering lifting appliances and gear that gives detailed guidance on the safe way of using them. These include the duty of employers to have a safety programme, the requirement for all lifting appliances (including parts thereof) to be of a good design and structure and strong enough for the purpose for which it is going to be used.

All lifting appliances and gear should be accompanied by instructions for use and should be certified annually by a mechanical engineer having a warrant to practise his profession. Moreover, they also have to examined by a competent person (a) before being taken into use for the first time; (b) one week after erection on site; (c) after any substantial alteration or repair and (d) monthly.

The code also outlines provisions for operators of lifting appliances, stating that they should be over 21 years of age and have been medically examined and certified fit to operate a lifting appliance. They should have also received appropriate and adequate training that should be repeated periodically.

Moreover, operators of every lifting appliance used outdoors, except those used for short periods, have to be provided with a safe cabin with full protection from weather and adverse climatic conditions and designed and constructed in accordance with ergonomic principles; a clear and unrestricted view of the area of operation and safe access to and egress from the cabin, including in situations where the operator is taken ill. The provisions also mention loads, platforms, wheelbarrows, long objects, landings and hoisting of loads.

When the lifting appliances are used on scaffolds, the code lays down that the parts of the scaffold should be carefully inspected by a competent person to determine the additional strengthening and other safety measures required. Moreover, any movement of the putlogs should be prevented and, if practicable, the uprights should be rigidly connected to a solid part of the building at the place where the lifting appliance is erected.

Over and above the provisions listed above, the same code delves specifically in the case of tower cranes and their safety. Various provisions are in fact outlined in the code of practice under section 5.3, namely:

¤ Where tower cranes have cabs at high levels, only persons who are capable and trained to work at heights should be employed as crane operators. An employer should ensure that crane operators must be over 21 years of age and should be medically certified to work as such.

¤ The characteristics of the various machines available should be considered against the operating requirements and the surroundings in which the crane will operate before a particular type of crane is selected.

¤ Care should be taken in the assessment of wind loads both during operations and out of service. Account should also be taken of the effects of high structures on wind forces in the vicinity of the crane.

¤ The ground on which the tower crane stands shall have adequate bearing capacity. Account should be taken of seasonal variations in ground conditions.

¤ Tower cranes should only be operated on gradients within limits specified by the manufacturers. Tower cranes should only be erected at a safe distance from excavations and ditches.

¤ Tower cranes shall be sited where there is clear space available for erection, operation and dismantling. As far as practicable, cranes shall be sited so that loads do not have to be handled over occupied premises, over public thoroughfares, other construction works or near power cables.

¤ Where two or more tower cranes are sited in position where their jibs could touch any part of the other crane, there should be direct means of communication between them and a distinct warning system operated from the cab so that one driver may alert the other to impending danger.

¤ The manufacturers' instructions on the methods and sequence of erection and dismantling shall be followed. The crane shall be tested before being taken into use.

¤ The climbing operation of climbing tower cranes shall be carried out in accordance with the manufacturers' instructions. The free-standing height of the tower crane should not extend beyond what is safe and is permissible in the manufacturers' instructions.

¤ When the tower crane is left unattended, loads shall be removed from the hook, the hook raised, the power switched off and the boom brought to the horizontal. For longer periods, or at times when adverse weather conditions are expected, out of service procedures should be followed. The main jib should be slewed to the side of the tower away from the wind, put into free slew and the crane immobilised.

¤ A windspeed measuring device should be provided at an elevated position on the tower crane with the indicator fitted in the driver's cab.

¤ Devices should be provided to prevent loads being moved to a point where the corresponding safe working load of the crane would be exceeded. Boarding or other items liable to catch the wind shall not be mounted on a tower crane other than in accordance with the manufacturers' instructions.

¤ Tower cranes shall not be used for magnet or demolition ball service, piling operations or other duties which could impose excessive loadings on the crane structure.

From investigations carried out by the Occupational Health and Safety Authority following incidents involving cranes, it results that most occupational accidents are not caused when using "uncertified" cranes but are the result of unsafe work practices. OHSA believes that as exemplified by various other countries, regulation alone does not result in a decrease in the number of injuries and fatalities. There are various issues that one needs to look seriously at since they have been identified as frequently being the root cause of work accidents.

These include undue pressure on contractors from clients to finish a project before its natural term of duration, as a result of which occupational health and safety are sacrificed. Another issue is the undue weighting in tender evaluation procedures that usually end up with a project being assigned to the cheapest bidder, in this case too, forfeiting OHS safeguards and quality of products used.

The Occupational Health and Safety Authority, however, fully concords with the Chamber of Engineers' plight to have hefty penalties meted out to offenders. Having petty fines given to people after a whole judicial process does little to help the OHS cause and definitely does not serve as a deterrent for abuse.

Dr Gauci is chief executive officer, Occupational Health and Safety Authority.