Every town or urban setup owes its stature to its outstanding infrastructure — buildings, bridges, roads and railways among other structures. Looking at their beauty, it’s hard to think of the difficulty people had in building these super structures.
And it’s even harder to picture how the tasks affect the health of construction workers. Part of the routine of these workers is the use of machines that produce vibrations that are detrimental to their health. Know what are the effects of vibration on the human body and how to prevent them.
So, where exactly does vibration come from?
There are two types of vibrations — hand-arm and whole body vibration.
Hand-arm vibration (HAV) is transmitted to your hands and arms while you are operating hand-guided equipment and hand-held power tools. Vibrations that hands and arms feel when holding materials being processed by machines also fall under this category.
Hand-arm vibration is felt by workers who frequently use jackhammers, grinders, chainsaws, drills, impact wrenches and riveters.
Harmful whole body vibration (WBV), on the other hand, comes from vehicle activity, engine vibration and rough surface conditions or bumpy roads and resistance forces.
These can be amplified by road construction activity, vehicle design, vehicle condition, vehicle suspension systems maintenance, vehicle speed, driver awareness and skills and work organisation can increase or decrease exposure to WBV.
Moreover, things like tool characteristics, work organisation and individual characteristics and skills can increase or decrease exposure to HAV.
Types of construction activities that generate vibration
These construction activities generate vibrations:
Road Construction is done using heavy equipment and machinery.
Machine operators experience vibrations at virtually every stage of the construction process. For starters, the laying of sub grade involves digging up the sub-soil and thoroughly compacting the sub-grade. In this, you use rollers weighing up to 8 tonnes.
These rollers are used to compact different layers. They make rapid humming movements which register as whole body vibrations on the operator.
Machines used in creation of curbs and other concrete materials also produce vibrations.
And when you are installing new valves, pipes, fittings and manholes, you need to drill and do excavation. These drillers and excavators frequently generate a lot of vibration.
Moreover, hand-arm vibration is produced in concrete removal, brought about by hammers and jackhammers.and tools used to shape building stones.
But it’s not only in construction site that vibrations can be observed. Construction workers in quarries also experience both hand-arm and whole body vibrations from pneumatic stone-chipping tools.
With so many activities causing hand-arm and whole body vibration, it’s important to understand how vibrations adversely affect the health of construction workers to minimise so to minimise the impact of such vibration.
Side-effects of vibration
HAV and WBV can cause harm if not kept in check.
WBV frequently causes or exacerbates health effects such as lower back pain. A person is likely to have lower back pain because their ligaments get loose due to the repeated shaking. Vibration can also cause mild to acute damage to the back bone and discs.
This kind of vibration may also cause motion sickness, damage to bones and reproductive organs, vision or balance impairment, digestion problems, heart conditions and changes in respiratory and endocrine systems.
The risk of having these health problems increases when a worker is exposed to WBV for a long time.
Another effect of HAV is Vibration-induced white finger (VWF).
VWF is the most common among persons who operate hand-held tools that produce vibrations. Symptoms of VWF become more amplified when exposed to cold.
Such vibration can cause change muscles, tendons, joints and bones and even impair the nervous system. These effects are collectively referred to as Hand-Arm Vibration Syndrome (HAVS).
Common symptoms of HAVS
- Blanching (whitening) of one or more fingers when exposed to cold;
- Tingling feeling on the fingers and loss of sensation;
- Pain and cold sensations in between episodic white finger attacks;
- Loss of grip strength; and
- Bone cysts in wrists and fingers.
These symptoms develop gradually, becoming severe over time. Problem is, HAVS may take up to several years before becoming clinically noticeable.
Overall, vibration induced health conditions develop slowly. You only feel pain in the beginning. But with continued exposure, this develops into an injury or ailment.
Ways to minimise the impact of vibrations
Here are some measures to minimise the dangers of vibration:
1. Right choice of equipment
Use low-vibration equipment and tools.
Using equipment that is for instance not powerful enough or is too small may entail longer time to complete the task. This translates to longer exposure to vibration.
2. Proper work practices
Improper use of equipment is one reason ailments develop from vibrations.
With this in mind, familiarise yourself thoroughly with how the equipment should be operated so you it would produce less vibration. Further, limit loads on hands and wrists and ensure you apply the right grip force.
Always wear the right gloves and clothing. Where possible, make use of suspension systems and jigs to take vibration and weight of equipment away from the operator.
3. Regular worker rotation
Rotating workers ensure they get the right break from such exposure to harmful vibrations. They would have enough rest so they need to handle equipment correctly and safely.
The effects of vibration can be prevented or at least contained provided you know how to do it. The above steps are enough to keep workers safe from the impact of vibrations.