These are

1. Breakdown losses: the most serious type of loss; to be avoided
2. Setup and adjustment losses (delaying the start of work)
3. Idling and minor stoppages (due to necessary minor adjustments)
4. Reduced speed losses (unable to run at full speed)
5. Start-up losses (pre-production breakdowns)
6. Quality defects (as a result of imperfect equipment), and Yield losses.

The six big losses have different causes and different solutions, so you need to know where you are. This means measuring each one. All items of equipment, but especially bottlenecks, should be analysed and the losses categorised. This is the first step to improvement. Inevitably you will find a Pareto (80/20) distribution, so concentrate on the vital few.

OEE (Overall Equipment Effectiveness). An effective way to measure availability and TPM performance is through OEE. OEE is closely related to the 6 Big Losses. See the next section.

"At its worst when new". This provocative statement goes to the heart of TPM. Why should an item of equipment be at its worst when new? Because, it may not yet be quality capable, standard procedures not yet worked out, failsafing (pokayoke) devices not yet added, operating and failure modes not yet known, 6 big losses not yet measured or understood, and vital internal elements not yet made visible (through transparent covers) or monitored by condition monitoring.

Visibility. Like JIT, TPM aims to make what is happening clear for all to see. This means maintenance records need to be kept next to the machine, problems noted on charts kept next to the machine, and following a 5 S exercise, vital components made visible by replacing (where possible) steel covers with transparent plastic or glass. Also, following 5 S, and leaks or drips are more easily seen.

Red Tags. Red tags are a common form of visible TPM. Maintenance "concerns" are written on red tags and hung on a prominent board on the shop floor. They remain there until action is taken. Red tags usually cover concerns that cannot be dealt with by operators.

Visual Checklists. Monitoring is very important in TPM. Therefore checklists are common. The status of each workcentre should be monitored against written standards, kept at the workplace. Checklists should be developed by the operators doing the work, not by an industrial engineer. They should also incorporate drawings or photos. A Japanese idea is that self developed sheets may not look as good as "professionally" developed sheets, but they are more effective.

Use of all senses. Most humans come to work with "hidden extras" which are not always used to best effect. So use them. First, there's the brain. TPM would like operators to think of better ways of maintaining equipment, keeping records, and making improvements. Then, there are the senses of smell, hearing, touch, seeing, and vibration detection. Humans are especially good at detecting changes in these (for example, you may not be aware of a noise, but will notice when the note changes). So tell the team leader, report it, record it. This is a simple, but not to be underestimated, form of condition monitoring.