This page is for anyone who has to run or read a time study: a work-study specialist, an engineer, or a merchandiser checking a costing sheet. A time study is not simply a stopwatch reading. It is a stopwatch reading, a rating of the operator's pace against a defined standard, and an allowance for rest and short delays, combined in that order.
This matters most to a work-study specialist at a factory, since skipping the rating step or guessing the allowance produces an SMV that looks measured but is not accurate. Delta Garments' own work-study specialist, already introduced in lesson 8.1.1, is timing sleeve attach, one operation in Order A's own operation breakdown, to show how each of the three steps changes the final number.
Without this method, two people timing the same operation on the same day can reach different standards, because one rated the operator's pace and one did not. This lesson gives you the three steps in order, and the one calculation that combines them.
You need: lesson 8.1.1's idea that work study has two connected parts. You do not need to have used a stopwatch before.
By the end of this lesson you can:
Not covered here: how a full operation sequence's SMVs are added into one garment total (lesson 8.1.3), and predetermined motion time systems, which build a time without a stopwatch at all (lesson 8.1.4).
| Term | Meaning |
|---|---|
| Time study | Directly timing a trained operator doing one operation, over several repeats, to build an accurate standard minute value for that operation. |
| Observed time | The raw time a stopwatch records for one repeat of an operation during a time study, before it is adjusted for the operator's pace. |
| Rating | A work-study specialist's judgement of how the observed operator's pace compares to a defined standard pace, expressed as a percentage (100% is standard pace). |
| Rated observation | One timed repeat of an operation together with the work-study specialist's rating of the operator's pace during that repeat. |
| Basic time | Observed time adjusted by the rating, giving the time a standard-pace operator would need for the same operation, before any allowance is added. |
| Standard minute value (SMV) | The standard time, in minutes, a trained operator needs to complete one operation on one piece, used to calculate a line's expected output and workload. |
A time study first records observed time: the raw stopwatch reading for one repeat. It then rates that repeat, comparing the operator's actual pace to a defined standard pace, producing basic time. Finally it adds an allowance for personal needs, fatigue and short unavoidable delays, producing the SMV. Skipping the rating step assumes every operator observed happened to be working at exactly standard pace, which is rarely true.
A person who has only rated one operator at exactly standard pace should not assume rating is always a formality. The three inputs stay the same; what they produce changes with the situation.
| What can differ | The shapes you meet | Why it matters |
|---|---|---|
| An operator working faster than standard pace | A rating above 100% (for example 110%) increases basic time above observed time, since a faster-than-standard operator's raw time understates what a standard-pace operator would need. | Using observed time unrated here would set a standard too fast for most operators to sustain. |
| An operator working slower than standard pace | A rating below 100% (for example 95%) reduces basic time below observed time. | Using observed time unrated here would set a standard too slow, understating the line's true capacity. |
| Export orders needing a defensible SMV for costing | An export buyer such as Northline Apparel may query a quoted making charge; a rated, allowance-added SMV, with each input recorded, can be defended step by step. | An unrated, unrecorded time cannot be defended the same way if a buyer or auditor questions it. |
| A domestic brand building its own line's standards | A domestic brand such as Cedar & Co., planning its own production run, applies the identical three-step method even though no external buyer will ever query the number. | The method does not change because the order is domestic rather than export; only who might ask to see it changes. |
Delta Garments' work-study specialist times the operator sewing sleeve attach on Order A over several repeats, using a stopwatch, and records an average observed time. Watching the operator's motions throughout, the specialist judges the pace to be exactly the factory's defined standard pace, so the rating given is 100%. Sleeve attach involves moderate handling but no unusual delay, so the specialist applies the factory's standard 12% personal, fatigue and delay allowance.
| Fact | What it tells the work-study specialist |
|---|---|
| Observed time averaged 0.55 minutes over several repeats | This is the raw reading, not yet adjusted for pace |
| The operator's pace was rated at 100%, standard pace | Basic time equals observed time exactly, since the rating makes no adjustment |
| A 12% personal, fatigue and delay allowance applies | Basic time still needs this addition before it becomes an SMV |
| No unusual delay or handling was observed | Nothing beyond the standard allowance is justified for this operation |
A 100% rating does not mean rating was skipped; it means the specialist judged, by comparing the operator's pace to the standard, that no adjustment was needed.
The worked numberThis example is illustrative, not a claimed fixed academy fact: sleeve attach's own observed time, rating and allowance are teaching figures, not measurements of Delta Garments' real line. With observed time 0.55 minutes and a 100% rating, basic time equals 0.55 minutes (0.55 × 1.00). Adding the 12% allowance gives the SMV.
Basic time, then SMV, for sleeve attach, from an observed time of 0.55 minutes, a 100% rating, and a 12% personal, fatigue and delay allowance.
A common mistake is treating the rating step as optional, on the reasoning that judging an operator's pace is subjective while a stopwatch reading is not. Recording observed time directly as the SMV silently assumes a 100% rating without ever checking whether that assumption is true. If the operator timed was working faster or slower than standard pace, the resulting standard is wrong in the same direction, and every plan built on it inherits that error.
A time study is not just a stopwatch reading. First, a stopwatch records how long an operation actually took, several times. Second, someone judges whether the operator was working at a normal pace, faster, or slower, and adjusts the time to what a normal pace would need. Third, a small extra amount is added for rest and short delays. Only after all three steps is the result a standard minute, a number every later plan can trust. Skipping the middle step and using the raw stopwatch time alone quietly assumes the operator was working at exactly normal pace, which is often not true.
Sara, the buyer at Northline Apparel, is reviewing Delta Garments' costing sheet for Order A before confirming the making charge. She notices sleeve attach is costed using an SMV of 0.62 minutes and asks Mona, the merchandiser, to show how that figure was built, not just to confirm it as a total.
Sara's message reads:
Can Mona show Sara a defensible build-up for sleeve attach's 0.62-minute SMV, or is 0.62 minutes simply a number written on the costing sheet.
Yes. Mona can show a defensible build-up, because Delta Garments' work-study specialist recorded each of the three inputs separately, not just the final SMV.
First, the observed time. The specialist recorded 0.55 minutes, averaged over several timed repeats of sleeve attach, not a single reading.
Second, the rating. The specialist judged the operator's pace at exactly 100%, standard pace, so basic time equals observed time: 0.55 × 1.00 = 0.55 minutes.
Third, the allowance. A 12% personal, fatigue and delay allowance was added to basic time: 0.55 × 1.12 = 0.62 minutes.
Mona should show Sara this three-step build-up rather than only the final 0.62-minute figure, since a buyer questioning a costed making charge is entitled to see the working, not just the result.
If Delta Garments had recorded sleeve attach's raw observed time of 0.55 minutes directly as its SMV, skipping both the rating and the allowance, the quoted making charge for this operation would be understated. The 0.62-minute SMV is 0.07 minutes higher than the unrated 0.55 minutes, a 13% understatement if the raw figure had been used instead.
Across Order A's 15,000 pieces, an understated SMV for even one operation understates the line's true workload for that operation by the same share, risking a line balance that assigns too few operators to sleeve attach and a piece rate that pays less than the operation's real, measured time deserves.
Open the SMV build-up calculator. On the sleeve-attach row, enter the observed time (0.55), the rating (100%) and the allowance (12%) into their own input columns. The basic time and SMV columns are calculated automatically from what you enter; do not type a number directly into either calculated column. Leave the other four operation rows for lesson 8.1.3, which builds the full table.
1. What are a time study's three inputs, in the order they are combined?
2. An operation has an observed time of 0.40 minutes and is rated at 90% (slower than standard pace). What is its basic time?
3. Why is recording a raw, unrated observed time directly as an operation's SMV a mistake?
| EN | AR | FR | TR | Meaning |
|---|---|---|---|---|
| Time study | دراسة الزمن | Étude de temps | Zaman etüdü | Directly timing a trained operator doing one operation, over several repeats, to build an accurate standard minute value for that operation. |
| Observed time | الزمن الملحوظ | Temps observé | Gözlemlenen süre | The raw time a stopwatch records for one repeat of an operation during a time study, before it is adjusted for the operator's pace. |
| Rating | تقييم الأداء | Évaluation d'allure | Derecelendirme | A work-study specialist's judgement of how the observed operator's pace compares to a defined standard pace, expressed as a percentage (100% is standard pace). |
| Rated observation | الملاحظة المقيَّمة | Observation évaluée | Derecelendirilmiş gözlem | One timed repeat of an operation together with the work-study specialist's rating of the operator's pace during that repeat. |
| Basic time | الزمن الأساسي | Temps de base | Temel süre | Observed time adjusted by the rating, giving the time a standard-pace operator would need for the same operation, before any allowance is added. |
| Standard minute value (SMV) | قيمة الدقيقة المعيارية (SMV) | Valeur minute standard (SMV) | Standart dakika değeri (SMV) | The standard time, in minutes, a trained operator needs to complete one operation on one piece, used to calculate a line's expected output and workload. |
You now know how one operation's observed time, rating and allowance combine into its own SMV. The next lesson repeats this for every operation in a garment's sequence, and adds the operations together into one complete SMV table. Back to the course map