Musculoskeletal disorders in cold logistics

Musculoskeletal disorders are particularly common in the logistics sector and represent an issue with human, social and economic implications. Improving employees’ working conditions can have a non-negligible impact on a logistics company’s productivity and performance. Flows can therefore be handled without incident, without adversely affecting the warehouse’s target quality of service and responsiveness and avoiding breaks in the supply chain.

Warehousing, picking and package preparation are the logistics activities where workers are most at risk of MSDs: delivery receivers, order pickers, machine maintenance technicians, vehicle loaders and forklift truck drivers are all on the front line.

What exactly are musculoskeletal disorders (MSDs) ?

According to French public health body Santé Publique France, musculoskeletal disorders “cover a wide range of conditions affecting the musculoskeletal system, which can be caused or aggravated by work activities. They generally involve pain and functional discomfort to varying degrees, but frequently on a daily basis.” 

The general and agricultural branches of the national health insurance system have published a reference document, Table no. 57, entitled “Affections péri-articulaires provoquées par certains gestes et postures” (Periarticular disorders caused by certain movements and postures), which is used to identify injuries covered by the social protection system.

What are the main causes of MSDs ?

It is important to point out that MSDs are not always work-related and can be caused by other conditions, such as pregnancy, endocrine disorders or non-work-related activities.

Certain non-work-related factors also favour the development of MSDs: advancing age, diabetes, obesity, inflammatory rheumatism, hypothyroidism are all sources of vulnerability to MSDs.

As regards work activities, it is mainly physical operations involving mechanical stress that are concerned: repetitive movements, extreme postures (arms above the shoulders), joint strain (twisting of the wrist), vibration, heat shock, etc.

What conditions are recognised as MSDs ?

Muscle pain, tendinitis, lumbago, neck pain, carpal tunnel syndrome, lateral epicondylitis (“tennis elbow”). These are just some of the conditions that may be recognised as MSDs.

Which parts of the body can be affected by MSDs ?

MSDs mainly affect the upper part of the body: shoulder, elbow, wrist, neck and back. Disorders affecting the lower limbs are much less common, but can occur.

To what extent is it necessary to be extra-vigilant in a naturally hostile work environment ?

Hostile work environment : cold

A work environment is considered as “cold” when the temperature of the air is below +15°C. The temperature in retail sector logistics warehouses varies between -26°C (areas where frozen goods are stored and picked) and +4°C (chilled goods and temperature on loading docks in winter).

It is therefore essential to provide operators with appropriate equipment.  Thermal clothing, insulated shoes, hand and head protection, sometimes even a snood to protect the nose and face. There are plenty of different solutions available. These items are subject to standards. Their effectiveness is therefore the subject of compliance checks.

In addition to the cold, workers are affected by humidity levels. These must be measured to ensure effective solutions are deployed to protect workers and avoid floors freezing.

This type of cold working environment is recognised as an arduous working condition.  Working in an environment with temperatures of -26°C therefore requires specific organisational measures: 90 minutes of working are followed by a 30-minute break.

In addition, workers exposed to temperatures of below +5°C for more than 900 h in a year are credited with points in a “personal prevention account” (C2P).

Finally, it should be noted that the warehouse manager is legally responsible for the safety of their staff.

MSDs and work postures : it’s all about movement

In addition to the work posture and the movements involved in handling operations, it is important to remember that preventive maintenance of equipment is crucial, to ensure that it is in good working order and meets the required standards.

Repetitive manual handling and carrying heavy loads are the main factors that trigger MSDs. Learning the correct postures for different jobs and the use of “support robots” are today seen as indispensable.

Focus on pushing and pulling

Containers, trolleys, pallet trucks and personnel lifts are all types of apparatus whose operation can involve pushing and pulling.   French standard NF X35-109 was therefore created to provide a framework for assessing this type of arduous work and to prevent work accidents and injuries. It sets a limit on acceptable pushing and pulling forces. This is calculated based on the initial force required to move the equipment plus the force needed to keep the apparatus moving.

The following factors also contribute to the risk represented by these push-pull actions:

• frequency of the actions,
• the amount of strain placed on the joints,
• the distance covered,
• quality of travel factors such as cleanliness of the floor, various obstacles, standard of maintenance of the equipment, productivity/performance requirements

It is highly recommended that all warehouse managers should encourage operators to take a course to get the CACES certificate (safe warehouse truck operation).

Avenues to explore.  As well as physical wear-and-tear, “push-pull” actions also cause operator fatigue and even exhaustion.  Handling heavy weights and repetitive movements end up wearying the operator, which is more than likely to impact their commitment and, as a result, their productivity.  There are, however, different support solutions that can be used to relieve them in their daily handling tasks. From simple pallet trucks to forklift trucks, a wide range of complementary equipment is now available on the market.

MSDs and preventive measures

A workstation ergonomics audit can help to optimise movements and eliminate unnecessary movements, which can have a serious adverse effect on a company’s performance. Not to mention the facilitation of the handling staff’s work.  An audit is a good way of taking stock of the situation and identifying areas for improvement and corrective and/or preventive actions that will benefit both productivity and the well-being of the staff.

To limit the risk of MSDs in a refrigerated logistics warehouse, particular attention should be paid to the three points below:

Know your work environment and make it safe:

• Thermal and acoustic insulation of buildings;
• Creation of buffer zones;
• Good maintenance of buildings and floors;
• First aid training and knowledge of the incident response protocol;
• Training in work postures and handling movements;

Have appropriate equipment:

• Appropriate thermal clothing – IREQ (Required Clothing Insulation Index);
• Regular checking of equipment compliance;
• Robot support equipment;

Organise working times:

• Limitation of the time workers are exposed to the cold;
• Rotation of workers between tasks, based on increased worker versatility;
• Management of breaks;
• Rules on the pace of working.

In conclusion, taking measures to limit MSDs in a logistics warehouse is also an opportunity to improve logistics processes by making a system more efficient, more virtuous and more responsible. This means making maximum use of the tools available and operators’ know-how.