ISO 5353 Fixture – Seat Index Point Tool

The ISO 5353 Fixture is a Seat Index Point Tool (SIPT).

The ISO 5353 SIPT is universally used in place of the J1163, which has some differences in contour.

The SAE J1163 standard states that it is applicable to seats designed for off-road, self-propelled machines for agriculture and forestry as defined in ISO 3339-0. The SIP can be determined on a seat by itself or with the seat located in its operating
environment. The ISO 5353 standard is applicable to seats designed for earth-moving machinery as defined in ISO 6165, and tractors and machinery. In both standards, the SIPT is a single-piece rigid buttock and thigh shell with a weight of 6 kg, without torso or legs. Weights are added to 40 mm forward of the SIP, bringing the total weight up to 65 kg, which is intended to represent the seat-borne weight of a midsize-male occupant. In these standards, the only measurement taken on the SIPT is the SIP and its location is often given relative to another reference point on the seat called a “fixing point,” interpreted as a mounting bolt or other designated reference feature.