Midterm 1 Flashcards
What is ergonomics
Ergonomics is designing work systems around capabilities and limitations of people.
What are the benefits of ergonomics?
Reduce potential for injury/discomfort, make work tasks easier, reduce fatigue, more productive at work and at home, improve work quality.
How is ergonomics different from other approaches that aim to prevent workplace injury?
Ergonomics isn’t just common sense, it is based on science. It is based on analysis of the job and scientific evidence and is evaluated in terms of their effect on the work system.
What is flexion?
Curling posture (bending wrist inwards, flexing biceps, spine flexion is bending forward and touching your toes, raising arms).
What is extension?
Opposite of flexion (pulling arm backwards, bending backwards).
What is abduction?
Moving away from the center of the body (shoulder abduction).
What is adduction?
Moving toward the center of the body (shoulder adduction).
What is pronation?
Rotating from neutral to palm facing down.
What is supination?
Rotating from neutral to palm facing up.
What is lateral bending?
leaning toward the side (lateral bending / spine lateral flexion).
What are the three basic strategies for anthropometric design?
- Extreme - fit (desk, clothes, door height) vs. reach (shelves, windows).
- Mean - (average man, counter top height, chair height).
- Adjustability - (bike, ski binding).
What is anthropometry?
The technology of measuring and quantifying various human physical traits.
Primary objective is to accommodate as many people as possible.
Engineering anthropometry is the application of anthopometric data to equipment, workplace, job design, and product design.
When do we design for “reach” and who is included and excluded?
Design for reach is the upper 95% (break pedals, controls, safety shutoff, excludes short people).
What do we design for “fit” and who is included and excluded?
Design for fit is the lower 95% (foot in a car, leg room on an airplane, excludes tall people).
Why don’t we design for everyone?
It isn’t possible to accommodate every design for every person because not everyone is proportional and we cannot collect data on every single person. Cost issues.
How are anthropometric data collected, where do you find the data and what kind of data is available?
Various measurements are collected in regards to the human body like distance from wrist to shoulder, leg length, shoulder height. This data can be found online or you can do measurements yourself.
When can we use one anthropometric dimension to predict another and when should we not do this?
Body dimensions are not well correlated with each other. When one uses more than one body dimension in a design the percentage of the population accommodated is less than for each dimension individually.
Height and shoulder height could be more proportional than something such as shoulder breadth and arm length.
What are some of the key assumptions we make regarding anthropometric data?
The data has a normal distribution, high variability and little correlation between dimensions.
How is anthropometric data changing over time?
PEople are getting taller, wider and bigger in general.
Why is there no such thing as the average sized person?
There is so much variability from person to person that there is not true average.
How do we combine anthropometric dimensions?
Adding or subtracting means and then using the final mean and correlation to get the standard deviation.
What is epidemiology?
A set of investigative methods for studying relationships between disease and risk factors exposure.
Based on the premise that disease occurrence is not random and full knowledge of causal mechanisms is not necessary for effective control.
Occupational epidemiology is investigations linking hypothesized health hazard exposures to disease.
What is surveillance and why do we do it?
The ongoing and systematic collection, analysis and interpretation of data related to worker health.
The purpose is to identify and track patterns of injury/illness in groups of workers and to identify risk factors that influence those trends.
Define hazard.
Workplace conditions or worker actions that could result in injuries, illness or other material damage or losses (heavy objects that need to be moved).
Define risk.
The probability that an event or development will occur, and severity of resultant harm or damage. Each risk is due to a hazard (probability of back injury).
Define risk factor.
Attribute or agent that is suspected to be related to the occurrence of a particular adverse health outcome (heavy lifting, static postures).
Define active vs. passive surveillance measures for health and hazard assessments.
Active methods include worker surveys and medical screening.
Passive methods include medical records, OSHA logs and accident reports.
How do you calculate incidence rate?
It is a measure of the frequency with which a disease occurs in a population over a period of time.
IR = #new cases during past 12 months/# of hours worked during the past 12 months.
How do you calculate normalized incidence and severity rates?
IR (normalized) = (# new cases during past 12 months x 200000 hours) / # of hours worked during the past 12 months
Severity rate = (# of lost time dates x 200000) / # of hours worked during the past 12 months
How do you calculate prevalence rates?
Prevalence = # of cases in population at time t / # in the population
Who is OSHA, what do they do?
Occupational Safety and Health Administration and they promote workplace safety, helps employers and employees reduce injuries, illness and death and mandates injury and illness record keeping.
What is the general duty clause?
Each employer has a duty to have a workplace that is free from recognized hazards and shall comply with occupational safety and health standards.
