Time and Motion Study Basics

A time and motion study is a structured observation that breaks a task into elements, times each one, and analyzes the motions used, in order to find the best method and set a fair standard time for the job. It is the measurement foundation that sits under standard work.

Before you can improve a job or set a fair expectation for it, you have to know two things: what the best way to do it is, and how long that way actually takes. A time and motion study answers both. It is one of the oldest tools in industrial engineering, older than the word "lean," and it is still the honest way to replace opinion ("that line should run faster") with a number built from watching the real work. Done with respect, it is how a plant sets targets people can actually hit, and how it builds the standards that lean manufacturing is built on.

What Is a Time and Motion Study?

A time and motion study is really two studies that grew together. Motion study asks what is the best method: which movements are necessary, which are wasted, and what sequence produces a good result with the least effort. Time study asks how long the chosen method should take when done by a trained worker at a normal pace. Combine them and you get a documented best method plus a defensible standard time for the job.

The output is not just a number. It is an element-by-element breakdown of the task, a chosen sequence, and a standard time that accounts for a normal working pace plus reasonable allowances for rest and unavoidable delays. That breakdown becomes the raw material for standard work for balancing a line, and for writing the work instructions operators are trained on.

Where Did Time and Motion Study Come From?

The two halves have two sets of parents. The time half comes from Frederick Winslow Taylor, who introduced stopwatch time study at Midvale Steel in the early 1880s as part of what became scientific management. Taylor's idea was to measure tasks empirically and set standards from data rather than custom, and it was genuinely powerful and genuinely controversial, because early time study was often used to push pace rather than improve method.

The motion half comes from Frank and Lillian Gilbreth in the early 1900s. They filmed workers to study movement frame by frame and classified the fundamental hand motions into units they called therbligs (Gilbreth spelled roughly backward). Their most famous result was bricklaying: by redesigning the scaffold and the way bricks and mortar were staged, Frank Gilbreth reportedly cut the motions per brick from around eighteen to under five and roughly doubled a bricklayer's output, without asking anyone to hurry. That is the enduring lesson of motion study: the biggest gains come from changing the method, not the pace.

How Do You Run a Time and Motion Study? A 7-Step Method

1. Select the job and tell people why. Pick a repetitive job worth studying, and be open with the operators about the purpose: better method and fair standards, not a stopwatch witch hunt. Studies done in secret poison trust and produce bad data because people change how they work when they feel judged.
2. Break the task into elements. Divide the job into small, clearly bounded work elements with definite start and end points, such as "reach and grasp," "position part," "run cycle." Elements should be short enough to time cleanly but large enough to read reliably.
3. Study the motion first. Before timing, watch how it is done and question every movement: what is reaching, searching, or double-handling that could be designed out. Improve the method before you time it, or you will enshrine waste in your standard.
4. Time multiple cycles and multiple operators. Record element times across enough cycles to average out variation, and watch more than one trained operator. The differences between good operators are where the best method hides.
5. Rate the pace. Judge each observed time against a normal working pace, a rating of 1.0 for normal, higher for fast, lower for slow, to convert observed time into normal time. This step takes practice and honesty; it is the part most open to dispute, so document your basis.
6. Add allowances. Apply reasonable allowances for personal needs, fatigue, and unavoidable delays to convert normal time into standard time. A standard with zero allowance is not a fair standard; it is a sprint nobody can hold all shift.
7. Document, apply, and revisit. Write up the chosen method and the standard time, use them to build standard work and balance the line, and re-study when the method, tooling, or product changes. A standard time is a living number, not a monument.

How Is Standard Time Actually Calculated?

Standard time is built up in two moves from what you observe. First you convert the observed time to a normal time by adjusting for pace: normal time equals observed time multiplied by the performance rating. Then you convert normal time to standard time by adding allowances: standard time equals normal time multiplied by one plus the allowance factor. So the full relationship is standard time equals observed time times rating times one plus allowances. The rating removes the distortion of watching a fast or slow worker; the allowance restores the reality that a person cannot value-add every second of a shift. Skip the rating and your standard depends on who you happened to watch. Skip the allowance and your standard is a stopwatch fantasy the floor will quietly ignore.

The stopwatch is not the only route. Where a job is highly repetitive, some plants use predetermined motion time systems such as MTM or MOST, which build a time by adding up published values for basic motions (reach, grasp, move, position, release) instead of timing the real task, which removes the rating judgment entirely. For jobs that are irregular or shared across many tasks, work sampling estimates how time splits across activities from many random observations rather than continuous timing. All three answer the same question, how long the work should take, and all three depend on first settling the best method; a precise time on a wasteful method is precision aimed at the wrong target.

How Does a Time and Motion Study Connect to Standard Work and Takt?

A time and motion study is the input; standard work is what you build from it. The element breakdown and standard times let you assemble a work sequence, load-balance it against takt time so each station fits the required pace, and split work fairly across a line. Without real element times, line balancing and takt planning are guesswork. The study also feeds cycle time analysis and the combination table that shows how manual, machine, and walk time interlock.

It connects to waste, too. Motion study is a direct attack on motion waste the reaching, searching, and double-handling at a station, and it surfaces the unevenness (mura) between operators that muda, mura, and muri names. Studying the work is how you see that unevenness instead of arguing about it. The rule that ties it all together: improve the method first, then set the time, then standardize, so the standard captures the best way rather than freezing the current way.

Is Time and Motion Study Still Ethical and Relevant?

It has a dark history and a bright present, and the difference is intent. Early time study was often used to squeeze workers, and that reputation still shadows the stopwatch. Used the modern way, it is the opposite: the goal is a better method that makes the job easier and a fair standard that people can actually hold, developed with the operators rather than done to them. Respect for the people doing the work is not a nicety here; it is what makes the data valid, because workers who trust the purpose show you the real job instead of a performance. When element times, method notes, and the resulting standards live on a tablet at the station instead of a clipboard in an office, the study stops being a once-a-year event and becomes a living record a team can see and improve against. That is the pattern Harmony deploys on running floors, turning paper standards and time records into live station-level capture with no rip-and-replace (see how Harmony digitizes floor paperwork). For what that looks like on a real floor, see the CLS field story.