Human Factors

Question 0

Revised Weight Limit (metric)

Answer 0

RWL(kg) = 23(25/H)(1-.003|V-75|)(.82+(4.5/D))(1-.0032A)*FM*CM

Question 1

Revised Lifting Equation (raw)

Answer 1

RWL = LC * HM * VM * DM * AM * FM * CM LC: load constant, 23kg (51lbm) HM: horizontal multiplier, 25/H(cm) or 10/H(in.), hands from ankle-midpoint VM: vertical multiplier, 1 - (.003 *|V - 75|) (cm) or 1 - (.0075 * |V - 30|) (in), hands from floor DM: distance multiplier, .82 + (4.5 / D) (cm), or .82 + (1.8 / D) (in). Vertical travel distance. AM: asymmetric multiplier, 1 - (.0032A), A in deg. FM: frequency mult. See large table. CM: coupling mult., hand-to-load coupling. See table.

Question 2

Revised Weight Limit (US)

Answer 2

RWL(lbs) = 51(10/H)(1-.0075|V-730)(.82+(1.8/D))(1-.0032A)*FM*CM H: horizontal location V: vertical location D: vertical travel distance A: asymmetric angle (deg)

Question 3

Lifting Index (LI)

Answer 3

LI=weight of load/RWL, LI > 1 is hazardous

Question 4

Wet Bulb Globe Temperature

Answer 4

Solar Load: WBGT = .7 NWB + .2 GT + .1 DBT No Solar Load: WBGT = .7 NWB + .3 GT WBGT: Wet Bulb Globe Temperature NWB: Natural Wet Bulb Temperature DBT: Dry Bulb Temperature GT: Globe Temperature

Question 5

Sound wavelength, frequency, and speed

Answer 5

F = V / lambda F: freq, Hertz V: speed lambda: wavelength

Question 6

Sound period & frequency

Answer 6

T = 1 / F T: period F: frequency

Question 7

Sound Pressure Level

Answer 7

SPL(dB) = 20 log (rms sound pressure measured) / (20 micropascals) RMS: root mean square, micropascals

Question 8

Addition of Noise Levels in a free field

Answer 8

Rule of thumb to sum two noises’ sound pressure levels

W/in 1: higher +3 2-3: higher +2 4-9: higher +1 => 10: =higher

Question 9

Multiple Decibel Addition

Answer 9

Add two lowest; Add result to next highest; Etc.

Question 10

Noise Reduction Coefficient

Answer 10

Arithmetic mean of absorption at 250, 500, 1,000, & 2,000 Hz

Question 11

Noise Exposure Time

Answer 11

t=8/(2^((L-90)/5)) t: allowable exp time, hrs L: loudness, dB

Question 12

Allowable Noise Exposure Time

Answer 12

t=8/(2^((L-90)/5)) t: allowable exp time, hrs L: loudness, dB

Question 13

Sound Level Meters

Answer 13

SLM: types 1 (precision) & 2 (general purpose) ISLM: integrates over time SA: spectrum analyzer

Question 14

SLM Scales

Answer 14

A: max 2,500 Hz, drops below 1,000 Hz B: 1,000, 500 C: 30 - 8,000 A most resembles human hearing, B or C engineering control or w SAs

Question 15

Hearing Impairment

Answer 15

Conductive, Sensorineural, Mixed, Central (as in CNS, as in interpretation)

Question 16

Oxygen Deficiency

Answer 16

< 19.5% by vol, ACGIH says 18%

Question 17

Heat Exposure

Answer 17

See OSHA table III:4-2. Permissible Heat Exposure Threshold Limit Value