Occupational Hazard, Warehouse Hazards, Fatigue Among Workers: Causes, Effects, Mitigating Strategies (essay).

Introduction: Overview of Occupational Hazards and Warehouse Hazards

Occupational Hazard can be understood as the dangers and risks associated with the job or occupation of the employee or policyholder (Collinsdictionary.com 2017). Hazard is a situation that can pose a significant threat to risk to the well being, health and even life of the individual as well as to property and environment, as is a source of potential harm or adverse effects due to previous, current or future exposure. Hazards can be dormant or potential (which only entails a theoretical possibility or risk of causing an adverse effect) or active (where it can create a situation of emergency). Anything that can be associated with or cause such adverse effects is called hazardous, and generally has one or more of characteristics like corrosive, toxic, flammable or reactive. Based on how the hazards cause the adverse effects, they can be classified as: Physical, Chemical, Biological, Radiological, Ergonomic and Behavioral (Occupational Health & Safety 2017).

Warehouse is a commercial room or building that specializes in the storage of commodities or merchandise (Merriam-webster.com 2017). Such buildings can be used by manufacturers, importers/exporters, retailer/wholesalers, transport companies, and businesses. Warehousing allows the execution of administrative and physical activities like receipt, identification, verification, inspection, storage and retrieval of goods (BusinessDictionary.com 2017). Warehouses can be sometimes a hazardous workplace, which can result in accidents that causes injury and even death of workers. Activities in a warehouse generally includes loading and unloading of goods from trucks or racks using hands or forklifts. Most of the hazards in a warehouse environment are related to storage and racking system; loading and unloading of goods; Slips, trips and fall; and manual handling of goods (Warehouse Hazards | Ministry of Labor. 2017).

Statistically speaking, warehouses is one of the most hazardous place to work in, and as per OSHA, the fatality rates due to warehouse accidents is higher than the national average in USA (Graphic Products Info. 2017). Given below are the anticipated challenges and hazards faced by workers in a warehouse:

The Leeds Warehouse has planned to introduce 24 hour shift, to ensure continued service for Amazing Suppliers. The warehouse staff will be working round the clock, while the administrative staff will work from 8 am to 8 pm. This will therefore result in different working shifts for the workers (morning, day/evening, and night shift), while administrative staff will have fewer shifts. The potential hazards of the working environment can include the ones outlined above, apart from the risk of fatigue caused by the long and rotating shift. Since Leeds Warehousing was already involved in warehousing activities, the general hazards of the warehouse have already been addressed and their solutions implemented in their work guidelines. However the new system of round the clock long shifts, night shifts, rotating shifts can entail additional hazards, which were not considered previously.

Anticipated Challenges and Hazards Faced by Workers

Caruso (2013) pointed out that long shift or work hours is associated with an increased risk reduced performance at job, and can also cause obesity, injury and chronic diseases. Extended work hours can also cause fatigue among workers and administrators, reduce the sleep time and cause disturbances in sleep patterns. Fatigue can further lead to errors at work, and can put at risk the health and well being of themselves as well as other working with them. Several studies have shown that poor sleep can lead to a reduced neurocognitive performance (Goel et al. 2009).  Studies by Dembe et al (2005) shows that risks of errors increases by 15% in evening shifts compared to morning shifts, while shift length of 10 hours increases the risk or errors by 13%, and for 12 hour shift, by 28%, compared to 8 hour shifts. The risks of long shift also increase by 17% by the third consecutive day of work, and by 36% by the fourth consecutive day of work. Long hours can also lead to poor mood, poor recovery from work, and a lowered perception of health (Caruso et al. 2004). While studies by Virtanen et al. (2012) shows that long working hours can increase the risk of coronary heart disease by 40%.

Symptoms like pain in the abdomen, heartburn, constipation, diarrhea, nausea, vomiting, appetite loss and indigestion are commonly reported by shift workers (Knutsson and Bøggild 2010), while Straif et al. (2007) pointed that disruption in the circadian rhythm can have carcinogenic effect. Similarly, studies have also shown that night shift increased the risk of cancer (particularly breast cancer by 48%).

As discussed above, fatigue is a significant and a very common issue seen among workers of long shift, night shifts and rotational shifts, due to a disturbance in their sleep patterns. It is therefore important to investigate the how fatigue can jeopardize the work and the health of the staff, and what can be done to prevent that hazard. An ergonomic investigation will also show how the identified factor (fatigue) can affect the efficiency of the workers.

Fatigue can be a subjective phenomenon, and when a worker reports of fatigue, it must be identified whether it means muscular weakness, physical exhaustion due to efforts, or fatigue not related to physical activity like emotional and nervous fatigue.  Sonne et al. (2015) points out that repetitive work can cause muscle fatigue, which can reduce performance, and quality of work, and can also cause musculoskeletal dysfunction on the long term. Similarly, mental fatigue can also adversely affect performance, and even delay the recovery of muscle fatigue. Their studies tried to examine target errors in a repetitive task, conducted before and after the onset of fatigue (mental fatigue only/ physical fatigue only) to understand how each of these fatigue type affects performance. The results showed that target errors increased with muscular fatigue, compared to nervous or mental fatigue.

Fatigue Among Workers and Long/Rotating Shifts

Similarly, Chen at al. (2014) showed that sustained mental activity led to an increased Electro Encephalogram coherence, and did not cause an improvement in efficiency. The EEG coherence variation and behavioral performance successfully highlights that continual mental task can cause mental fatigue. It can be assumed that the administrative staff, who are required to overlook and supervise the work of the other staff, are more prone to mental fatigue, while the workers are more prone to physical fatigue, due to their continued and repetitive physical work.

Tanaka, Ishii and Watanabe (2015) also added that mental fatigue can cause over activation of the visual cortex of the brain and a decreased alpha frequency wave in this region. That is correlated to a cognitive impairment.

The cognitive deficit, poor muscular performance, can increase the risks of general errors in the workplace, thereby increasing the chances to accidents (mentioned earlier).      

Figure 1: Causes of Fatigue; source: (Sadeghniiat-Haghighi and Yazdi 2015)

Fatigue can have differential effects on skills, entailing differential definitions, and can be due to different causes. Due to such multivariate cause effect relations, no gold standard exists for the measurement of Fatigue. At workplaces, employees feel reluctance to share their feelings of fatigue readily, especially during an investigation of an incident. This makes measurement of fatigue at workplaces even more difficult. However, several instruments exist for the measurement of fatigue, some of them contradictory. Using these dimension and severity, of fatigue can be measured. (Yazdi and Sadeghniiat-Haghighi 2015).

Hence highlights the importance to compare and contrast some of these models to identify the most effective in the given scenario.

The most efficient single dimension scare of fatigue is severity scale. For example, the Five Point Verbal Rating Scale (from severe to no fatigue), and Visual Analog Scale -10 cm (from no fatigue to worst possible fatigue) are effective single dimension scale for measuring fatigue (Wierwille and Ellsworth 1994).

Multidimensional Assessment of Fatigue (MAF) involves rates the degree and severity of fatigue that was experienced the previous week. A derivative of this scale is the Piper Fatigue Scale which additionally includes the ability to measure interferences and timing of fatigue (and Rogers 1997).

Epsworth Sleepiness Scale correlates fatigue to sleep and depression, and enables the detection of fatigue in workers. The scale measures or ranks how sleepy a person is, and thus how prone the person is of falling asleep at work. The scale has 8 items, assessing the likelihood of dozing off under different scenarios, and the perception of the severity of fatigue is rated on a 0-4 scale, and a total core between 0-24 obtained my adding the ratings of the items. A score above 10 generally means excessive sleepiness (Haghighi et al. 2013).

Measurement and Mitigation of Fatigue in the Workplace

Horne Ostberg Questionnaire (HOQ) has 19 questions that can help to identify the time when the respondents would prefer to go to sleep or wake up, instead of when they actually do. It classifies people based on their sleep patterns as Lark (morning), Owl (night), and no preference. This scale can be used in the assignment of shift to people (Horne and Ostberg 1976).

Laboratory testing of performance is an assessment of aspects related to performance at work like short term memory, reaction time and vigilance. It can be a good indicator of the efficiency of the worker and their ability to perform their work without jeopardizing themselves or others. An abbreviated version of the scale is the Psychomotor Vigilance Test.

Sleep monitoring using sleep questionnaires, actigraphy, sleep diaries and polysmnography can be used to measure the quantity and quality of sleep one gets. Sleep Disorders, and thus risk factor for fatigue can be identified using this test.

Symptom Distress Test (SDS) is a questionnaire consisting of 13 items. That includes symptoms of distress like, tiredness, nausea and pain. These items are measured with a 5 point Likert scale. This test can measure the “degree of distress” from no symptom to worst symptoms on all items.

Multi-Latency Test of Multi Sleep Latency Test studies sleep dysfunctions. It measures the sleep latency (time from stating a nap to the onset of sleep), and essentially measures how sleepy people are.

Cognitive testing can involve technology and software to test people’s neurocognitive skills through some short tests on reflex, visual cognition and response time.

Measurement of Depression is an effective way to identify fatigue. Profile of Moods test has six items like fatigue, confusion, depression, vigor, anger and tension.

As discussed before, Fatigue can have multiple causes, giving rise to diverse array of effects on a varied scale. There are considerable different types of measurement tool for fatigue. Similarly, solutions to these problems are also multivariate.  Hence, it is important to use a combination of strategies to combat fatigue at work. The strategies can either be preventative, being implemented before the shift, during resting time or it can be operational, being used during the shift. It should be noted that disruption in the circadian rhythm is strongly correlated to sleep dysfunction. Therefore efficient method of combating fatigue in a night shift environment can be to reduce the effect of the disruption of circadian rhythm. Some of the suggestible strategies are:

Minimizing loss of sleep:

Good quality and quantity of sleep is needed for optimum efficiency at work. For most people, an average of 8 hours of sleep is sufficient. Getting sleep lesser than the average causes sleep deprivation, and can cause fatigue. It is important therefore to get a proper rest and sleep before the start of the shift. Studies shows that risk of fatigue increases in early start shifts, 12 hour shifts, or overtime. Thus a gap of 24 hr must be given between 12 hour shifts (Folkard, Lombardi and Tucker 2005).

Different studies indicated that short naps can improve the mood and performance, apart from increasing alertness, decreases sleepiness. The effectiveness of these naps however depends upon length and timing of the nap and the sleep inertia. Studies even suggest that performance can increase after a short nap, apart from increasing safety at workplace. It is measured that a Rapid Eye Movement (REM) sleep of 90-120min being the most effective, while the positive effects of 30 min naps can also reduce fatigue (Dawman, Chapman and Thomas 2012; Folkard, Lombardi and Tucker 2005).

Regular and timely sleeping to prevent circadian disruption. Keeping a comfortable environment (quite, dark, warm) that promotes sleep in the bedroom of the employees. Avoiding caffeine, alcohol or smoking before sleep.

Resynchronization of the circadian rhythm to night shifts can be done by a timed exposure to bright light and administering melatonin (exogenous). During evening, exposure to bright light delays circadian rhythm, while exposure during morning advances it. While melatonin has a powerful effect in synchronization. Administering it in the evening can advance circadian rhythm, while administering it in the morning can delay it (Sadeghniiat-Haghighi et al. 2011; 2008).

Alert enhancing medications like caffeine, amphetamine and modafinil can be considered (Folkard, Lombardi and Tucker 2005). Other methods can include social interaction, physical activities or just drinking coffee (Dawson et al. 2012).

Fatigue Risk Management System (FRMS) manages workplace fatigue, utilizing the knowledge in sleep science. It has a multilayered defense system that can monitor workplace hazard caused by fatigue, when used along with Safety Management System (SMS) (Dawson, Chapman and Thomas 2012). These layers are:

Level 1: Provide opportunity for adequate sleep

Level 2: Confirming that employees are fir for duty based upon the amount of sleep they got

Level 3: Detection of symptoms of fatigue

Level 4: Assessment of Fatigue in identified individuals

Level 5: Control of fatigue based on the assessed severity

These steps can help in fatigue reduction/elimination or fatigue proofing the work environment.

Therefore, it can be inferred that long shift of 12 or more hours can have significant hazards. The table below compares the risks of 12 hour shift compared to 8 hour shift:

Keeping these factors in mind, the following shift timing should be considered, involving 2 shift times for administrative staff (covering 12 hours between 8am-8pm) and 3 shift times for the workers (covering 24 hours).

Administrative staff shifts 1: 0800hrs to 1700hrs

Administrative staff shifts 2: 1100hrs to 1600hrs

Workers shift 1: 0800 to 1700hrs

Workers shift 2: 1600hrs to 0100hrs

Workers shift 3: 0000hrs to 0900hrs

HOQ Test can be used to decide which employees to be assigned what shift, keeping their preference in mind. Additionally, during night shifts, it should be ensured that the work environment remains interactive, and the workers take breaks during work, to wear out the fatigue. I would also suggest installing coffee vending machines, as caffeine can be a good stimulant.

Conclusion

Thus, fatigue poses a significant hazard in the workplace, which becomes even more of a concern in workplaces, which are already considered hazardous. Accidents in hazard prone zones have often resulted in grave injuries and even death. Many of such accidents have been directly related to fatigue, and thereby leading to making mistakes at work. Such accidents can put the life and wellbeing of the worker as well as the co-workers in peril. Hence proper measures must be taken to identify, assess, and measure fatigue, and manage it among individuals experiencing it. Also, preventative measures must be used, which can be tried before the work hours, and aimed for an individual to get proper sleep. Workers also should be regularly screened for their quality of sleep and to identify sleep dysfunction, especially among those working in early shift or night shifts. Also, the shift rotation should be minimal, to allow the worker to synchronize their circadian rhythm. Administration of melatonin, under medical supervision can be considered to help the process.

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