TIME STANDARDS:ADJUSTMENTS TO TIME AND ALLOWANCES

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3. ADJUSTMENTS TO TIME: ALLOWANCES

3.1. Three Levels of Time

Time is reported at three levels:

1. Observed time: The raw (unadjusted) time taken by the worker. It does not have any rating, allowance or learning adjustment.

2. Normal time:

Normal time = (observed time)(rating)

The observer estimates the pace of the worker in relation to normal pace. Normal time is the time an experienced operator takes when working at a 100% pace. See Chapter 54 for more details.

3. Standard time: For allowances expressed as a percent of shift time:

Standard time = normal time / (1 - allowances) For allowances expressed as a percent of work time:

Standard time = normal time (1 + allowances)

It is a policy decision by the firm whether to give allowances as a percent of shift or work time. Normal time needs to be increased from standard time by personal, fatigue, and delay allowances.

3.2. Personal Allowances

Personal allowances are given for such things as blowing your nose, going to the toilet, getting a drink of water, smoking, and so on. They do not vary with the task but are the same for all tasks in the firm. There is no scientific or engineering basis for the percent to give. Values of 5% (24 minutes in a 480-minute day) seem to be typical.

Most firms have standardized break periods (coffee breaks)—for example, 10 minutes in the first part of the shift and the same in the second part. It is not clear whether most firms consider this time as part of the personal allowance or in addition to it.

The midshift meal break (lunch) is another question. This 20–60-minute break obviously permits the worker to attend to personal needs and recover from fatigue. Yet lunch usually is not considered as part of allowances—even if the lunch period is paid.

Some firms give an additional break if work is over 8 hours. For example, if a shift is over 10 hours, there is an additional break of 10 minutes after the 9th hour.

In addition, some firms give an additional allowance to all workers for cleanup (either of the person or the machine), putting on and taking off of protective clothing, or travel. In mines, the travel allowance is called portal-to-portal pay; pay begins when the worker crosses the mine portal, even though the worker will not arrive at the working surface until some time later.

3.3. Fatigue Allowances

The rationale of fatigue allowances is to compensate the person for the time lost due to fatigue. In contrast to personal allowances, which are given to everyone, fatigue allowances are given only for cause—for fatigue. No fatigue? Then no fatigue allowance!

Another challenge is the concept of machine time. With the increasing capabilities of servo- mechanisms and computers, many machines operate semiautomatically (operator is required only to load / unload the machine) or automatically (machine loads, processes, and unloads). During the ma- chine time of the work cycle, the operator may be able to drink coffee (personal allowance) or talk to the supervisor (delay allowance) or recover from fatigue. Thus, as a general principle, give a fatigue allowance only for the portion of the work cycle outside the machine time.

The following will discuss the fatigue allowances developed by the International Labor Organi- zation (ILO 1992). They were supplied by a British consulting firm. Use of the ILO values is complex. Remembering that fatigue allowances are given for work time only (not machine time), sum the

applicable fatigue allowance points. Then, using Table 1, convert points to percent time. For a more detailed discussion of allowances, see Konz and Johnson (2000, chap. 32).

The fatigue factors are grouped into three categories: physical, mental, and environmental.

3.3.1. Physical: Physical Fatigue

Table 2 shows how the ILO makes a distinction among carrying loads, lifting loads, and force applied. In the NIOSH lifting guideline, the lift origin and destination, frequency of move, angle, and container are considered as well as load.

3.3.2. Physical: Short Cycle

Table 3 gives the fatigue allowance to allow time for the muscles to recover.

3.3.3. Physical: Static Load (Body Posture)

Table 4 gives the allowance for poor posture.

3.3.4. Physical: Restrictive Clothing

Table 5 gives the allowance for restrictive clothing.

3.3.5. Mental: Concentration / Anxiety

Table 6 gives the allowance for concentration / anxiety.

3.3.6. Mental: Monotony

Table 7 gives the allowance for monotony. In the author’s opinion, allowances for monotony, bore- dom, lack of a feeling of accomplishment, and the like are questionable. These factors are unlikely to cause fatigue and thus increase time / cycle. These factors primarily reflect unpleasantness and thus should be reflected in the wage rate / hr rather than the time / unit.

3.3.7. Environmental: Climate

Table 8 gives the allowance for climate.

3.3.8. Environmental: Dust, Dirt, and Fumes

Table 9 gives the allowance for dust, dirt and fumes.

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The second column (0) gives the 10s, and the remaining columns give the units. Thus, 30 points (0 column) = 15%; 31 points (1 column) = 16%; 34 points = 17%. The percent allowance is for manual work time (not machine time) and includes 5% personal time for coffee breaks.

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ILO (1979) considers temperature / humidity, wet, and ventilation. For temperature / humidity, use the average envi- ronmental temperature. For wet, consider the cumulative effect over a long period. For ventilation, consider quality/ freshness of air and its circulation by air conditioning or natural movement.

3.3.9. Environmental: Noise and Vibration

Table 10 gives the allowance for noise and vibration.

3.3.10. Environmental: Eye Strain

Table 11 gives the allowance for eye strain.

3.3.11. Overview of Fatigue Allowances

In general, the fatigue allowances seem to have inadequate range. In addition, note from Table 1 that points are not converted one for one to percent. A person with 0 points for fatigue gets a 10% fatigue allowance. A person with 30 points gets a 15% fatigue allowance—an increase of only 5%.

In addition, neither the length of the workday nor the number of days / week is specified. Presum- ably it is 8 hr / day and 5 days / week. The author does not recommend changing the allowance for working a shorter or longer time period. Any adjustment should be in the discipline level (see Section 5.2.2).

3.4. Delay Allowances

Delay allowances should vary with the task but not the operator. They compensate for machine breakdowns, interrupted material flow, conversations with supervisors, machine maintenance and cleaning, and so on. If the delay is long (e.g., 30 minutes), the operator clocks out (records the start and stop time of the delay on a form) and works on something else during the clocked-out time. Delays usually permit the operator to take some personal time and reduce fatigue; that is, they also serve as personal allowances and fatigue allowances.

How do you set a delay allowance? One possibility is to record the delays during a work sampling study or time study. For example, if there were 4 minutes of delay during 100 minutes of time study, then 4% could be used for the delay allowance.

Errors in delay allowances can occur from poor sampling or changing conditions.

To obtain a valid sample of delays, the sample must represent the total shift, not just the middle of the shift. That is, the delays must be observed at the start and stop of the shift and just before and after lunch and coffee breaks, in addition to the middle of the shift. Also observe delays on the second and third shifts.

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From International Labour Office, Introduction to Work Study, 4th (Rev.) Ed., pp. 491–498. Copyright © Interna- tional Labour Organization 1992.

ILO (1979) considers whether the noise affects concentration, is a steady hum or a background noise, is regular or occurs unexpectedly, is irritating or soothing. Consider the impact of the vibration on the body, limbs, or hands and the addition to mental effort as a result, or to a series of jars or shocks.

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Conditions change over time. A reasonable procedure is to give delay allowances an expiration date, for example, two years after being set. After two years, they must be redetermined.

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