Week 10 Lecture: Lecture 7 ULA2 Flashcards
RULA
- Items
- Benefits
- Limitations
- Validity
- Reliability
- Assesses awkward posture of the upper body + adds force
- Quick
- Does not consider duration, recovery time, hand-arm vibration; only assesses worst case posture; requires separate assessment of the right and left sides of the body
- high predictive validity for neck and lower arm; low predictive validity for upper arm and wrist; high inter-rater reliability
Assessment of Repetitive Tasks
- Items
- Benefits
- Limitations
- Validity
- Reliability
- Frequency and repetition, force, awkward postures, additional factors (psychosocial elements), breaks and duration
- Solid for initial assessment. Great for the lay person. Health Safety Executive also provides ideas for solutions to address identified porblems
- Not comprehensive. for an ergonomist, would want to complement with further assessments as needed.
- Moderate concurrent validity for work tasks of duration of 3.75 hour; moderate inter and intra-rater reliability
Revised strain index (RSI)
- Items
- Benefits
- Limitations
- Validity
- Reliability
- measures risk of hand and wrist MSD; intensity, frequency, duration of exertion, posture, hours; rated on 5 point scale of light to near maximal. posture is considered high risk if 10 or greater
- comprehensive consideration of factors known to contribute to MSI; simple and accessible tool; clear directions; inexpensive
- does not consider mechanical compression (contact stress), environmental factors (cold temperature), vibration,
- strong predictive validity and good-strong inter-rater reliability
Composite strain index (COSI)
- what is it
- how to calculate it
- Benefits
- Limitations
- Validity
- Reliability
- quantifies biomechanical stressors for complex tasks and job rotation using the RSI. score is comprised of RSI1 (subtask with highest exposure) plus an incremental
increase in physical exposure, ΔRSI, as each subsequent subtask is added to the peak subtask, - equation: see paper - https://canvas.sfu.ca/courses/87767/files/25751791?wrap=1
- comprehensive consideration of factors known to contribute to MSI; simple and accessible tool; clear directions; inexpensive
- does not consider mechanical compression (contact stress), environmental factors (cold temperature), vibration,
- strong predictive validity and good-strong inter-rater reliability
Cumulative
Strain Index (CUSI)
- how to calculate
see paper https://canvas.sfu.ca/courses/87767/files/25751791?wrap=1
ACGIH TLV HAL
- items
- what tasks is it most useful for?
- benefits
- limitations
- validity and reliability
American conference of governmental industrial hygienists threshold limit value for hand activity level
- reviews repetition and force. frequency of exertions and percentage of duty cycle are involved in calculations. force is estimated by observation or maximum voluntary contraction.
- useful for tasks with 4 or more hours of exposure that are monotask hand work
- does not consider a comprehensive number of risk factors. other factors are deferred to analysis of ergonomists
- good predictive validity for hand, wrist, elbow disorder; strong inter-rater reliability of cyclical and non-cyclical tasks
Distal Upper Extremity Tool (DUET)
- items
- based on?
- benefits
- limitations
- validity and reliability
- force and repetition
- in vitro fatigue failure of tendons and epidemiological studies
- great if interested in preventing tendon failure; allows you to look at job as a whole and calculate total cumulative damage and probability of distal upper extremity outcome for whole job
- does not take into consideration rest time, and what is done during rest time
- high predictive validity but reliability is not well understood/examined
UTAH shoulder moment model
- items
- what does it calculate
- body weight, horizontal distance from load to shoulder joint, load weight in lb, forearm angle in degrees, upper arm angle in degrees
- calculates % max moment capacity using shoulder moments
3DSSPP UPPER LIMB
- purpose
- benefits
- limitations
- validity and reliabiltiy
- provides % capable for strength measures
- 2D and 3D modes and can simulate task on variety of populations. localized fatigue strength at 25th percentile
- highly visual which is good for showing to clients
- steep learning curve. does not allow for manual adjustment of radial/ulnar deviation or flexion/extension of the hand at wrist. hands are always in neutral position and does not consider coupling
- good predictive validity for static strengths and joint strengths; poor validity for upper limb and shoulder - reliability unknown
Shoulder tool
- items
- benefits
- limitations
- validity and reliability
- lever arm, load, reppetitions per day
- calculates cumulative risk due to all loading situations person may encounter in work
- looks at cumulative risk. easy to use, accessible, contextualizes loads and repetition using term cumulative damage.
- does not look at body position or detail what type of damage is calculated (tendon vs ligament vs muscle). does not consider anthropometry of worker
- not able to account for all possible loading situations such as when arm is directly above shoulder or when pushing forward at shoulder height with arms straight out infront and in line with shoulder. this creates no moment but does still stress the shoulder
- strong predictive validity for shoulder and neck pain. but reliability is unknown
ARM FORCE FIELD (AFF)
- items
- validity and reliability
- items: force direction, hand position, body orientation
- easy to use, input values on excel, simple and focuses on most important variables. model position is easily adjustable. instruction is provided and clear
- % capable is categorized as either risky or safe. no middle ground. does not consider trunk twisting. primarily focused on strength but without consideration of moments generated at joints or awkward postures
- good to excellent predictive validity of manual arm strength - reliability unknown
How is hand-arm vibration measured?
- accelerometers then compared to iso guidelines
Higher frequencies and durations more problematic than lower ones
