Standard Work Instructions on the Shop Floor

What standard work is

Standard work is a lean term with a specific meaning. It is the current best way to do a job, written down as a sequence, with the time each step takes, the amount of work in process the sequence needs, and the quality checks built in. It is called standard because everyone who does the job does it that way, until someone finds a better way and the standard changes.

A standard work instruction is that sequence written for the person doing the job. It sits below an SOP, which says what a process is and who owns it, and above a checklist, which only records that steps happened. If you want the full split, work instruction vs SOP goes through it.

What goes in one

The classic document has four parts, and a shop does not need to be running a full lean program to use them.

The sequence. Numbered steps, one action each, in the order they happen. Load the part, set the stop, close the clamp, start the cycle. Not "set up the machine."

The time. Cycle time per step, or per the whole sequence, and takt time if you run to one. This is the part most shops skip, and it is the part that turns a document into a standard: without a time, there is no way to tell whether the operator on second shift is doing the same job.

The standard work in process. How many parts are in the cell at once, and where. One in the vise, one on the deburr bench, one in the gauge. This keeps the sequence honest when two people share a cell.

The checks. Which dimensions get measured, with what, how often, and what the limits are. In a shop that is audited, this is the part the auditor reads first.

Add the revision and the date to the first page, and a photo for any step that is easier to show than to say.

"Standard" only holds on the floor

Here is the part the lean textbooks assume and the floor does not deliver. A standard work instruction is only standard if every operator is working from the same revision. The moment there are two copies of it in the building, there are two standards, and the one at the machine is usually the older one.

This is not a hypothetical. A revision goes out, the copy in the binder gets swapped, and the copy taped inside the guard door does not. Second shift runs the old sequence for three weeks. Nobody finds out until the parts do not match, or an auditor asks which revision is at the machine and gets two answers.

Keeping it standard means three things:

1. 1One controlled copy at the point of use, and none anywhere else. The binder in the office is a reference, not a working copy.
2. 2The revision on that copy is the one that was released, and anyone can check that in five seconds.
3. 3Each operator has read the current revision, and there is a record of it.

Paper can do the first. It cannot do the second or the third without someone walking the floor after every release.

Doing it without the walk

Put a QR tag on the machine, and have it open the current revision of the instruction on the operator's phone. The tag does not change when the document does, so a release means uploading the new revision and nothing else. The operator scans, reads the sequence and the checks, and confirms they read that revision. The confirmations become a register, per document and per revision, which is what an auditor means when they ask to see who was trained on the current standard.

That is the delivery half of standard work, and it is the half a small shop can put in place in an afternoon. The writing half is the four parts above, and if you would rather not start from a blank page, the work instruction template produces a Word document with the sequence, the checks, and the sign-off table already laid out.