TS ISO 7870-2

TS ISO 7870-2 is a guidance standard for understanding and using the Shewhart control chart approach in statistical control of a process. Control charts make process variation visible over time, helping distinguish routine fluctuation from unusual changes that may indicate a special cause.

Purpose and scope of the Shewhart approach

The focus of this standard is limited to statistical process control methods that use only the Shewhart system of charts. In practical terms, Shewhart charts monitor process data against a central line and control limits to assess whether the process is behaving as expected. They are widely used in manufacturing, services, and other process environments as a fundamental tool for monitoring stability. The document also briefly introduces some supplementary topics consistent with the Shewhart approach, including warning limits, analysis of trend patterns, and process capability.

Context within statistical process control

From a general technical perspective, control charts provide more insight than viewing individual results alone because they combine information about process spread and time-related change. Shewhart-type charts are commonly used to watch short-term variation, detect process shifts, and support root-cause investigation when behavior becomes unusual. The standard also makes clear that other types of control charts exist for different situations, so its coverage is specifically the Shewhart family rather than the full range of control-chart methods.

• Monitoring process behavior with control charts
• Statistical process control based on the Shewhart system
• Brief introduction to warning limits, trend analysis, and process capability
• Recognition that other control chart types are used in other situations