Controlled arithmetic · not a conformity decision
Linear-Size Interval Worksheet
Transcribe one declared numeric size interval and compare it with a recorded observation range. The worksheet performs arithmetic only; it does not infer the applicable GPS operator, evaluate form or envelope requirements, include measurement uncertainty, or declare ISO conformity.
Entered interval and observations
Use one unit throughout. Signed deviations are added to the nominal value exactly as entered.
Arithmetic implemented
UL = N + dU
T = UL − LL
S = xmax − xmin
mL = xmin − LL
mU = UL − xmax
N is the entered nominal value; dL a dU are the signed entered deviations; LL a UL are the resulting numeric limits; xmin a xmax are the recorded extrema. “Inside” means only xmin ≥ LL a xmax ≤ UL for the entered numbers.
All quantities retain the selected unit. Decimal point and decimal comma are accepted. Scientific notation, units inside numeric fields, partial numeric strings, non-finite values and inconsistent intervals are rejected.
What this worksheet deliberately does not calculate
- Form error: the spread between maximum and minimum observed sizes is not automatically roundness, cylindricity, straightness or any other form deviation.
- Envelope or maximum-material boundary: two extrema do not establish whether an actual surface violates a perfect-form boundary.
- Specification operator: the applicable size characteristic and operator must already be defined in the controlled specification.
- Conformity or nonconformity: no uncertainty budget, guard band or ISO 14253-1 decision rule is implemented.
- Fit, function or interchangeability: numeric containment alone does not establish assembly function.
Standards status and scope
| Document | Verified public status | Relevance and boundary |
|---|---|---|
| ISO 8015:2011, edition 2 | Published; ISO records confirmation in 2021. | Fundamental GPS concepts, principles and rules for specification and verification. The public ISO card does not provide enough normative detail to turn this worksheet into an ISO compliance test. |
| ISO 14405-1:2025, edition 3 | Published 2025-08; replaces withdrawn ISO 14405-1:2016. | Requirements for indicating linear sizes and default/special specification operators for applicable features of size. This worksheet does not infer or select an operator. |
| ISO 14253-1:2017, edition 3 | Published; confirmed in 2023. | Decision rules for verifying conformity or nonconformity, including cases close to limits and measurement uncertainty. Those rules are not implemented here. |
The arithmetic formulas above are general interval arithmetic, not formulas claimed to be prescribed by ISO. Exact principles, operators, modifiers and decision-rule implementation require licensed controlled copies of the relevant standards.
Official source records
- ISO 8015:2011 official record — edition, status, lifecycle and public abstract; accessed 2026-07-15.
- ISO 14405-1:2025 official record — current edition, scope and replacement lifecycle; accessed 2026-07-15.
- ISO 14253-1:2017 official record — current edition, scope, confirmation and uncertainty boundary; accessed 2026-07-15.
- ISO 14405-1:2016 official withdrawn record — replacement evidence; accessed 2026-07-15.
