Lifting machinery and lifting tackle safety in construction

Lifting operations are inherent to many occupations in the construction industry. They can be performed manually or by using lifting equipment. Both manual lifting and mechanical lifting operations can put construction workers at great risk of injury or death. The costs of accidents and ill health related to lifting operations are immense. This article describes the risks associated with lifting operations in the construction industry and discusses measures to reduce the risks associated with using lifting machinery namely, tower cranes, mobile cranes and gantry cranes.

Lifting Machinery

Lifting machinery such as Tower Cranes, Mobile Cranes, Gantry Cranes, Teleporters and Hoists must be designed and constructed in accordance with generally accepted technical standards. Lifting machinery and all its components must be thoroughly examined and subjected to a performance test, also known as a load test. This load test must be performed as prescribed by the standards to which the lifting machinery was manufactured. The load test must be carried out by a competent person that has been certified by the Engineering Council of South Africa as a Lifting Machine Inspector (LMI). The whole installation must be subjected to these performance tests before it is put into use, every time it is dismantled and assembled and thereafter at intervals not exceeding 12 months.

In addition to load testing, lifting machinery and all components that form an integral part of the lifting machinery, must be examined by a competent Lifting Machine Inspector (LMI) every 6 months. The findings of the inspections as well as the load test results must be recorded in a register. This register must be kept on the site or premises where the machinery is used.

All lifting machinery must be clearly marked with the Maximum Mass Load (MML) which it is designed to carry safely. If the mass load varies with the conditions of use, then a table showing the maximum mass load for each position must be posted where it is visible to the operator.

Lifting machinery such as Tower Cranes must have a brake or device capable of holding the maximum mass load should the power supply fail. This will prevent the uncontrolled downward movement of the load. Tower Cranes must also be fitted with suitable limiting devices to prevent overloading.

Lifting machinery may only be operated by a person who is specifically trained to use that particular type of machinery. Operators of lifting machinery must receive annual medical tests and be declared fit to operate the type of machinery for which they are appointed to operate.

Lifting Tackle

Just like lifting machinery, lifting tackle such as chains, chain slings, ropes, straps, shackles and hooks must also be subjected to a load test. The load test must be done by a competent person. In addition to the load testing, all lifting tackle must be inspected by a competent person that has been appointed in writing at intervals not exceeding 3 months. The results of the annual load tests, as well as the 3 monthly inspections, must be recorded in a register. The register must be kept up to date and be kept on the site where the tackle is being used.

Lifting tackle should be identified and colour-coded in accordance with the 3 monthly inspections. This will make it easy for supervisors, operators and workers to see if the most currently inspected tackle is used on site.

Now that we understand the difference between lifting machinery and lifting tackle and know at what interval they must be tested and inspected let’s have a closer look at some of the lifting operations that are used in the construction industry. We will look at what dangers are involved with these operations as well as illustrate what is required to achieve ultimate safety!

Tower Crane

Tower cranes are specialized machinery and are an important component of many construction sites.  A crane risk assessment must be conducted by an appointed competent person. Make sure that the crane is erected and used only as per the safe work procedures of the risk assessment, failing which, the crane could be very dangerous and could even collapse!  

It is the responsibility of the appointed operator to conduct visual inspections of the tower crane’s structure whilst ascending and descending the crane’s access ladder. The operator must record the findings of these inspections in a register and keep it on the crane. Any visible defects must be reported to the site supervisor or manager immediately.

Care must be taken of the crane’s electrical supply by making sure:

• All the electrical cables are secured.
• The DB is closed and protected.
• Signs containing warning notices stating the presence of the DB are posted

This will ensure good electrical safety when working with or around tower cranes. Bare wires or open, live DBs can be very dangerous.  They can electrocute workers or be susceptible to rain and water damage creating a very dangerous environment. 

Crane hooks must be pop marked and if the hook has opened beyond the safe limit, the hook must be replaced. All hooks must be fitted with safety latches and they must be functional. Make sure the MML is displayed and that the limit devices for both the mass and wind overloads are operational at all times.

Make sure the condition of the crane’s access components has been checked. This will include the ladder, backrests and landing platforms. It is highly recommended that all crane access ladders be fitted with appropriate fall arrest systems. This will ensure ultimate safety for the operator.

Make sure the cabin has been well-constructed, not damaged and free from rust. Check the windscreen to make sure it is intact and visibility from the cabin is not obstructed. The hooter and siren must be in working order.

Strobe lights or aviation lights are to be fitted to cranes that might be hazardous to aircraft.

Mobile Crane

The fundamental advantage of a Mobile Crane is its ease of transportation and its flexibility in handling different types of loads or cargo quickly. This makes a mobile crane very useful and an ideal solution for work on a construction site.

Here are the items one needs to check before using a Mobile Crane:

• Inspect the rearview mirrors, windscreen, windscreen wipers and indicators to make sure that they are fitted correctly, are in good condition and are operational.
• Hooters must be checked that they are working.
• Tire condition and pressure must be checked on a regular basis. All of the wheel nuts must be inspected to ensure that they are correctly fitted.
• Lights must be operational. It is important that headlights and taillights are in good condition.
• All grease nipples and all joints must be greased.
• There are to be no oil leaks. If any, report them to the supervisor immediately.
• Hydraulic pipes must be in good condition and attachments in working order with no leaks.
• Do not operate the mobile crane if you see any hydraulic leaks!
• Battery condition must be inspected. Batteries must be secured, terminals secured and no corrosion present. The boom must be in good condition with no visible damage. If this is not the case, degradation and defects must be reported.
• Cable and sheaves must be greased and have no visible damage or corrosion. Any defects must be reported.
• Brakes must be checked to be in good working order.
• By-pass valves must be fitted correctly, securely mounted, functional and no leaks must be present.
• A Deflection chart must be fitted, be in good condition and visible to the operator.
• Outriggers' condition must be inspected, foot plates fitted correctly when used when lifting.
• Do not use the mobile crane unless a risk assessment has been performed by a competent person on the outriggers and ground conditions on which the outriggers are going to be placed.

Banksman

A Banksman is a skilled person who directs the operation of the crane and is in charge of the crane movements from the point of loading and unloading at ground level.  The Banksman directs the crane operator and controls all operations via hand signals. All signals made by the Banksman or rigger must be noted and adhered to for safety and to ensure that order is maintained on site.

Gantry Crane

Gantry cranes are used to lift and move items around a working area This makes them ideally suited for work in a factory, plant or machine shop. The Gantry Crane must always, be in good working condition, load tested and inspected. The following recommendations should be followed to ensure safety when using Gantry Cranes: 

• The Gantry Crane’s logbook must be kept up to date and available in the yard where it is used.
• The operator must be trained and appointed in writing.
• Make sure the MML is clearly displayed on the crane as well as the crawler beams.
• The operator must at all times observe and adhere to the hand signals, given by the Rigger or Slinger.
• The area where there are Gantry Cranes in use must be marked with warning notices. Signage such as "Crane Overhead" must be strategically placed and in good condition to ensure the safety of those working in the area.
• Make sure the hooks are throat pop marked, with the safety latch fitted and functional. Make sure load limiting switches are fitted and fully operational.
• Finally, lifting machinery and lifting tackle must only be used as per the requirements of the Occupational Health and Safety Act and Regulations as well as the manufacturer’s operating instructions.

Neil Enslin

Head Occupational Health and Safety

Sources:

Occupational Health and Safety Act and its Regulations

Master Builders SA Construction Manual and audit system