Overview
ISO 9896:1996 - "Plastics traps for discharge pipework systems inside buildings" specifies performance, design and testing requirements for plastic traps used in domestic discharge pipework. It covers sanitary appliance traps (tubular, bottle and urinal traps) and gully traps intended for the evacuation of domestic waste waters inside buildings. The standard defines material, geometrical, mechanical, chemical and functional characteristics and includes test methods in annexes A–K.
Key topics and technical requirements
- Scope and trap types: Sanitary appliance traps (demountable or non‑demountable), tubular, bottle and urinal traps; gully traps and gully traps with separate outlet connections.
- Materials: Bodies must meet the performance requirements of the relevant “head documents” for thermoplastics used in soil/waste fittings - ISO 3633 (PVC‑U), ISO 7675 (PVC‑C), ISO 7682 (ABS), ISO 7671 (PP) and ISO 8770 (PE‑HD). Elastomeric seals must meet the corresponding head‑document requirements.
- Geometrical characteristics: Nominal trap sizes and inlet/outlet combinations are specified (see tables in the standard). Minimum seal depth is 50 mm unless local codes require greater depth.
- Mechanical and thermal tests: Torque test for threaded connections (inlet nuts and other threads must resist 15 N·m without damage - Annex B); elevated‑temperature cycling and oven stress‑relief tests per the head documents.
- Chemical and durability tests: Stress‑cracking resistance (Annex C) and other durability tests appropriate to the plastic material.
- Functional tests:
- Rate‑of‑flow: Performance for inlet sizes up to 50 mm is specified and verified using the rate‑of‑flow test (Annex D). Example flow values given for small sizes (e.g., 25 mm = 0.5 l/s; 32 mm = 0.65 l/s).
- Seal retention: Tested per Annex E with defined acceptance criteria.
- Self‑cleansing / anti‑blockage: Non‑demountable traps must pass a self‑cleansing test (Annex F); traps must accommodate passage of a 10 mm ball.
- Watertightness and marking: Traps must meet watertightness and pressure requirements of the relevant head document. Minimum marking: manufacturer’s name/trade mark, nominal size and body material.
Applications and users
ISO 9896 is used by:
- Manufacturers and product designers of plastic plumbing traps and gullies
- Test laboratories and quality assurance teams validating trap performance
- Building services engineers, plumbing specifiers and consultants selecting compliant traps
- Regulators and authorities referencing standardized requirements in codes and procurement
Typical applications include sanitary appliance connections (basins, sinks, urinals), floor gullies and other domestic drainage points inside residential and commercial buildings.
Related standards
Key referenced standards (“head documents”):
ISO 9896 provides a practical product specification framework to ensure safe, durable and maintainable plastic traps for domestic discharge pipework.