The shift in recent years within Europe towards a more risk-based approach to health and safety regulation has also offered opportunities for greater efficiency. In many cases this potential has remained largely untapped.
For example, in the UK, the Lifting Operations and Lifting Equipment Regulations (LOLER) 1998 regulations specify a maximum period of 12 months between thorough examinations – see Hoist June/July 2002 pp41-3 – of lifting gear, six months if it is lifting people. But it also offers an alternative based on a competent person’s risk assessment.
In theory, an examination scheme allows the organisation to focus on the most safety critical areas, ensuring that examinations can be conducted more cost-effectively, or the benefits of enhanced levels of safety achieved without incurring a financial premium.
In practice, the overwhelming preference within industry has been to stick with prescribed six or 12 month maximum intervals. Clearly an examination scheme is not always the best option, and should only be adopted when the advantages outweigh the disadvantages.
Who might benefit
An examination scheme is most likely to be appropriate when the condition of the equipment depends primarily on the amount and/or nature of the usage, and such usage can be monitored in some way. It may also be appropriate when the condition of various parts of the equipment deteriorates at markedly different rates, and/or when it is only used occasionally and can be adequately quarantined and examined when required for use.
A crane fitted with a duty cycle monitor is an obvious candidate, but there are other ways of monitoring usage. For example, a crane fitted with a grab for handling refuse in an incinerator plant will lift the maximum capacity of the grab on each occasion. The load moved and the load path will therefore average out to a fairly constant value and the total work done by the crane can be assessed accurately enough from either the hours worked or the total tonnage handled.
An example where parts of the equipment deteriorate at varying rates is the turbine house crane in a power station. Typically these are in the order of 120 tonne capacity and have an auxiliary hoist of about 10% of the main hoist capacity. For most of the crane’s working life, only the auxiliary hoist is used. The crane structure is only loaded to its full capacity when a major plant overhaul takes place, a foreseeable event which can be planned for in advance. Hence the examination scheme can focus on those components affected by regular use and require a more comprehensive examination of the main hoist and structure when the crane is used to assist with a major plant overhaul. Similarly, the special purpose lifting accessories employed for the overhaul, such as special slings and lifting beams, can be quarantined in between and only examined when needed for use.
In contrast, the periodic approach to examination is more likely to be effective when one or more of the following conditions apply: the amount of use cannot easily or cost-effectively be monitored; the equipment may deteriorate due to time and/or storage conditions, whether or not it is used; the equipment is vulnerable to damage each time it is used and the thorough examination is in effect a ‘long stop’ to detect any deterioration not picked up during the in-service inspection; the pattern of use is well-established and all parts are subject to a similar rate of deterioration.
Putting theory into practice
To come to a firm conclusion on the potential benefits of a scheme of examination, it is also necessary to consider what is involved in its implementation. The objective of a thorough examination is to check whether the equipment is fit for the coming period of service. An examination scheme should therefore ensure that all parts of the equipment upon which safety depends are thoroughly examined by appropriate means and at such frequency as will allow defects to be detected and remedial action to be taken before the equipment becomes dangerous. Clearly, unforeseen events may occur between scheduled thorough examinations which render the equipment unsafe. It is therefore vital that regular in-service inspections are also conducted and, in the case of lifting accessories, ideally before each use.
If adopted, the LEEA recommends that a written scheme of examination should contain at least the following:
1. The name and address of the owner of the lifting equipment.
2. The name and contact details of the person responsible for the equipment. If responsibility is divided, e.g. between maintenance and operations, there may be more than one name. However it should be clear who should be notified in the event of a dangerous or potentially dangerous defect and to whom reports should be sent.
3. The name, qualifications and address of the person drawing up the scheme. If the competent person is not working on their own account, the name of their employing organisation and their position in that organisation should be given.
4. The identity of the equipment, i.e. a description including the make, model and unique identity number.
5. If it is a fixed installation, the location of the equipment. Alternatively, in the case of portable and mobile equipment, the location where it is based.
6. Details of any information or references used in drawing up the scheme. For example, the manufacturer’s manual, expected component life, or specific information on the design life of the crane structure and mechanisms as detailed in clause 7 of ISO 12482-1.
7. The basis for the scheme. For example, is it based on hours of service, duty monitoring, or examining certain parts or components at different intervals to other parts?
8. Details of any data logging system fitted, including a list of the parameters monitored and the means of data retrieval, monitoring and storage.
9. What determines when the thorough examination shall take place and who is responsible for monitoring that and instigating the examination?
10. Identification of the safety critical parts requiring thorough examination.
11. A risk assessment. This should take account of: the condition of the equipment, the environment in which it is to be used, and the number and nature of lifting operations and the loads lifted. It should include details of any assumptions about usage, expected component life etc.
12. The frequency of thorough examination of those parts identified as safety critical, taking into account the degree of risk associated with each part. This may include time or loading or duty cycle limits and vary for different parts of the equipment.
(Note: Where the scheme is based on the hours of service the LEEA recommends that a maximum period between thorough examinations is always specified as equipment can deteriorate whether used or not.)
13. The method of examination of those safety critical parts, which may include the degree of dismantling required and the techniques employed e.g. visual examination, measurement, NDT, operational test, load test.
14. The rejection criteria or a reference to where this information may be found.
15. An indication of the resources required to prepare the equipment and carry out the thorough examination. This may include qualified personnel, workshop facilities, specialist NDT and metallurgical facilities.
16. Any changes to equipment condition, operational or environmental parameters that will require a review of the scheme by the competent person. These may include damage to the equipment, change of use from general duty to heavy duty, or moving from an inland location to a marine environment.
17. A requirement for the person responsible for the equipment to monitor its circumstances of use and inform the competent person who drafted the scheme of any changes.
18. The date of drawing up the scheme and the date at which any routine review is required.
The above list also indicates the investment of time that has to be made at the outset. Indeed, the need for a comprehensive assessment of the equipment and operations is probably one of the main reasons that those responsible generally find it easier to opt for straightforward 6 or 12 month maximum periods, regardless of their individual circumstances. However, in a significant number of cases, this practice is undoubtedly resulting in companies spending more than is necessary on the examination of equipment, or failing to achieve optimum standards of safety from their current level of expenditure.
