Ergonomics: Environmental Factors

• This presentation explores crucial environmental factors in ergonomics, like lighting, noise, and temperature, affecting well-being and productivity.
• The agenda includes: Lighting, colors, temperature, noise, vibration and chemical agents

Lighting and Colors

• Lighting and colors are critical for human work because a large part of environmental information captured occurs through vision
• Proper lighting and color planning can prevent errors in reading visual instruments.
• Good lighting and color schemes increase job satisfaction productivity.
• These elements also reduce errors, fatigue and accidents

About Lighting

• Measuring photometric variables is essential when evaluating and designing lighting for workplaces
• Key factors include:
• Adequate intensity
• Controlled contrast
• Types of lamps

Photometric Variables

• Luminous Intensity (Candela (cd)): Light emitted by or reflected from a luminous surface
• Luminous Flux (Lumen (lm)): Luminous energy emitted from source
• Illuminance (Lux (lx)): Amount of light that hits a surface.
• Luminance (Candela per square meter (cd/m²)): Amount of light emitted/perceived by a surface.
• Reflectance (%): Proportion of light reflected by a surface in relation to incident light

About Colors

• Ergonomic colors in work environments are critical for peoples comfort, productivity and well-being.
• They directly influence the perception of space, mood, and even task performance

Importance of Color

• Color is important for:
• Visual Comfort and Eye Fatigue
• Perception of Space and Illumination
• Safety and Signaling
• Productivity and Efficiency

Temperature

• Humans have a large capacity to tolerate climatic differences in comparison to other primates.
• Not all climatic conditions are considered comfortable or conducive to efficient work.
• It is imperative to monitor temperature so that it does not affect employee's health

Thermal Influences

• Thermal environment, mainly the air temperature and humidity, directly affects human work performance.
• Lab and industry studies confirm these effects on productivity and accident risks

Thermal Influences: Working in High Temperatures

• Heavy work generates a lot of heat through metabolic processes.
• Evaporation of sweat is the only mechanism to eliminate body heat.
• Imbalance can lead to increased body temperature, which can be dangerous which can be mitigated by:
• Improving environmental conditions to promote sweat evaporation, with ventilation and appropriate clothing.
• Creating barriers between heat source and worker using reflective surfaces or protective clothing.
• Reducing work pace or provide breaks to allow sufficient time for the body to eliminate excess heat

Thermal Influences: Heat disease

• Workers can suffer heat illness due to dehydration caused by excessive sweating in high external temperatures.
• If dehydration occurs, sweat production decreases and the body's internal temperature tends to increase.
• In extreme situations, the thermoregulation mechanism fails, and body temperature can rise to 41°C.
• Blood pressure drops and blood flow to vital organs is insufficient.
• The skin becomes rosy, hot, and dry.
• If not moved immedately people can collapse

Thermal Influences: Working in Low Temperatures

• Cold weather means increased muscle effort.
• At 5 °C, muscle tension increases by 20% and accelerates fatigue.
• Cooling peripheral tissues, especially in the hands and feet, reduces strength and neuromuscular control.
• This can lead to injuries and accidents
• In the event internal body temperature drop below 33 °C, leads to collapse of the central nervous system

Thermal Influences: Mental Tasks

• High temperatures (above 32 °C) impair the perception of signals.
• Decreased performance in mental tasks is evident above 33°C.
• People tend to make riskier decisions
• Very cold temperatures hinder mental concentration because discomfort causes distractions

Noise

• Noise is often defined as simply an unwanted sound.
• An alternative definition views it operationally as an auditory stimulus that doesn't provide useful information for doing work.
• Physically, noise consists of a intricate mixture of various logarithmic vibrations and its measured in decibel (dB) units.

Noise Duration

• Long-term noises, also called continuous noises, are those of background, occurring with some uniformity throughout the workday.
• Short-lasting noises (one or two minutes) cause reduced performance, both at the beginning and at the end of the noise period.
• Very short duration noises that may cause impact, are those with some duration of just a few seconds, are especially damaging when bursts of noise reach 110 dB to 135 dB.

Noise impact levels

• 50 dB(A): Is considered as a silent environment, however 25% of people will face sleeping problems
• 55 dB(A): Maximally adequate for environments that need silence
• 60 dB(A): Adequate for job environments in day-time
• 65 dB(A): Maximum Noise Allowed.
• 70 dB(A): Inadequate for office environment. It's hard to have a conversation
• 75 dB(A): It is needed to shout for a conversation
• 80 dB(A): Conversation will be very hard
• 85 dB(A): Maximally Noise Allowed for working day

Exposure Times

• 85 dB (A): 8 hours max exposure
• 90 dB (A): 4 hours max exposure
• 100 dB (A): 1 hours max exposure
• 105 dB (A): 30 minutes max exposure
• 110 dB (A): 15 minutes max exposure
• 115 dB (A): 7 minutes max exposure

Temporary vs permanent hearing loss

• Hearing loss can vary in type i.e temporary or permanent
• Exposing employees to noise above 85 dB could cause hearing problem
• Continual exposure can exacerbate a cumulative effect to make hearing deficiency permanent or uncorrectable.
• Reduction of hearing can hurt job quality including their job trajectory.
• Workers may find complications to detect signs that is sonar in jobs in where vocal communication is frequent

Influence on Work Performance

• Noise may cause headaches, harm temporary remembering skill and make oral communication difficult.
• Higher noise by 85dB enhance tension, tiredness, affect process that need remembering concentration and accuracy
• Performance hurts beyond 2h of noise vulnerability, especially during training.

Noise Mitigation Principles

• Act on the source (most impactful).
• Redesign machinery or replace with quieter machines
• Isolate sources (enclosures in isolation booths for total or partial sound barrier)
• Reduce reverberation. In this case, amount of noise depend on environment and its respective sources and spread. Use noise filtering materials e.g. carpets including wall curtains.
• When its applicable, relocate operations and cluster them from factory and use noise filters.
• As final resort, use of personal defensive kit e.g. hearing security. A primary initiative can educate people on noise risks

Health and Safety Risks of Vibration

• Vibration refers to a physical object oscilation and a section around a space/site
• Vibration is categorised into: Whole vibration, transmitted arm including motion sickness

Preventive Steps

• Utilization include anti vibration and regular rest breaks and analysing vibration amount
• Health outcome include: Circulation disease, muscle and sinew damage. Reduce amount of exposure
• The maximum duration is governed based on ISO 2631/1978 based on alteration, in frequency, acceleration and movement

Chemical Agents

• Chemical can harm employees through swallowing, inhaling including touching skin
• This may damage workplace operation

Impact to The Workplace

• Reduce capacity of physical including respiratory performance.
• Fatigue that jeopardise cogitative effectiveness
• Escalated workplace injury and leave
• Should utilise defensive safety gears plus environmental filters

Environment Best Practices

• Use adjustable equipment plus keep watch that workers is in compatible with
• Take advantage light from solar sources and reduce dependence on artificial generators
• Apply soundproofing materials through peaceful section