Definitions
Every term below is used with exactly this meaning throughout the specification.
| Term | Definition |
|---|---|
| Baseline measurement | A measurement of an effect taken immediately before a group’s exposure begins, against which that group’s later measurements are compared. See Test Conditions |
| Cycle | One operation of every moving part through its full range. Rate and per-part rules: D and G: Particulate Testing |
| Depth tier | One step of the W depth scale. See W: Water |
| Dose | The mass of test medium, in grams, applied to a unit. Calculated per D and G: Particulate Testing |
| Effect | A change in a unit observed during or after testing, recorded with an effect letter |
| Effect letter | A letter from the closed list in Effect Letters. Lowercase means the effect is within tolerance; uppercase means it is a failure |
| Eligible unit | A lab-tier unit at or above the standard wear level, from which IDRS digits can be derived. See IDRS Short Code |
| Enclosure breach | Dust or liquid inside a sealed compartment |
| Exposure area (A) | The sum of length × width of the largest face of each rigid section of a device, in cm² |
| Failure | An effect that meets its uppercase threshold. A level or step at which a failure appears is failed |
| Failure letter | The uppercase effect letter naming the failure at the level or step above the rated level |
| Full code | The complete IDR code covering all four groups, e.g. IDR1 U2 D3 G2rC W52E (hypothetical). Grammar: Code Format |
| Full dose (F) | The dose per 100 cm² of exposure area at level 9 (100% cumulative dose). Set separately for D and G |
| Group | One of the four test categories, U (usage), D (dust), G (grit) and W (water), each written as one segment of the full code |
| Headline code | The single full code published for a lab-tier test. See Reporting |
| Ingress | Test medium or water visible inside a unit’s openings (ports, grilles, holes, button gaps, display or hinge gaps), below the outer surface. Medium resting on the outer surface is not ingress |
| Ladder | The ordered sequence of levels (U, D, G) or steps (W) that a unit is taken through |
| Level | One step on a group’s scale: 0–9 for D and G, U0–U4 for U. W is graded by depth tier and time tier |
| Medium (test medium) | The particulate material applied in a D or G test. See Test Media |
| Moving part | Any part that moves in normal use: hinges, slides, buttons and keys, ports and port covers, trays, and rotating crowns or dials |
| Rated level | The level reported by a group’s digit(s): the highest level passed, or for W the rated depth and time tiers |
| Rigid section | A part of a device’s body that does not fold or slide relative to itself. A slab phone has one; a foldable or laptop has two |
| Sealed compartment | An interior part of a device that its seals are intended to keep dust and liquid out of |
| Short code | The IDRS code, e.g. IDRS1 315 (hypothetical). See IDRS Short Code |
| Standard wear level | The wear level an IDRS code is issued at. See U: Usage |
| Step (W) | One exposure at one depth tier for one time tier. See W: Water |
| Test tier (tier) | The class of test, home or lab. “Tier” used alone always means test tier. See Test Tiers |
| Time tier | One step of the W duration scale. See W: Water |
| Tolerance | The range in which an effect is recorded in lowercase: from its lowercase threshold up to, but not including, its uppercase threshold |
| Unit | One physical device under test |