12 — Explosion proofness, icing and fire applicability

DO-160 Display Qualification | A-P02 — Draft / Not Released

Learning objective: Screen Sections 9, 24 and 26 against the display installation and materials.

Use the zone and function to decide applicability

Explosion proofness concerns whether the equipment can ignite a specified flammable atmosphere under the applicable test conditions. A display installed in a location where that hazard is relevant needs the appropriate allocation and complete-assembly consideration. A cockpit label alone does not select or exclude the section. Hot components, switching circuits and enclosure paths can matter.

Icing addresses the selected icing environment and its consequences. Consider exposed controls, optical surfaces, seals and any cooling or drainage feature. A cabin display protected from the allocated icing exposure may have a different applicability rationale from an exposed installation. Environmental ice on a surface is not the same test as condensation or cold-soak operation.

Section 26 addresses fire and flammability under its stated categories and scope. It does not replace every aircraft material, flame, smoke, toxicity or structural-fire requirement. Display plastics, adhesives, optical films, touch layers, cables and finishes may also be controlled by aircraft specifications or other applicable methods. Name each invoked requirement and its evidence boundary.

Material substitutions

An apparently equivalent adhesive can change more than optical clarity: it may affect moisture absorption, flammability, outgassing, mechanical behavior and bond durability. A component material certificate must match the actual formulation and applicable test conditions. If the assembly method or thickness changes, assess whether the original evidence still applies.

Exercise

A supplier offers a plastic resin flammability rating and declares the entire display compliant with every aircraft fire requirement. Worked response: request the exact material and configuration evidence, the invoked test methods, specimen conditions and scope. Allocate remaining assembly and installation requirements. A material rating may be useful evidence but cannot support an unlimited claim.

Matrix output

For each of Sections 9, 24 and 26, record the source of the exposure assumption, proposed category or exclusion rationale, affected surfaces/materials, acceptance criteria, evidence needed and the person responsible for resolving remaining applicability questions.