ISO 15854 pdf free download

ISO 15854-2021 pdf free download.Dentistry一Casting and baseplate waxes.
5.6 Behaviour on softening (Type 2)
The wax shall soften without becoming sticky or crumbly and shall be mouldable without breaking or delaminating when tested in accordance with 8.
This requirement shall not apply to baseplate preforms where a suitable square test piece cannot be cut.
5.7 Residue on artificial teeth (Type 2)
The wax shall not leave a visible residue on either ceramic or synthetic polymer teeth when tested in accordance with 81.
5.8 Behaviour of colouring material (Type 2)
The colouring material shall neither separate from the wax nor impregnate the gypsum mould when tested in accordance with 87.
5.9 Adhesion on storage (Type 2)
Adhesion due to storage of the wax shall be such that, when tested in accordance with 8.8. there shall be no evidence of damage to wax surfaces. Wax and separating paper surfaces shall separate cleanly and readily.
NOTE The separating paper might not cover the whole area of the wax sheet.
5.10 Residue on ignition (Type 1)
lithe manufacturer does not state a value for the residue on ignition, the value as determined in accordance with 8.9 shall be no greater than 0,10 % by mass.
lithe residue on ignition is greater than 0,10 % by mass, this value shall be stated by the manufacturer and the value as determined in accordance with 8.9 shall be not more than 20 % greater than that stated value.
5.11 Biocompatibility
See ISO 7405 and ISO 10993-1 for guidance on compatibility in respect of waxes that are offered for use in the mouth or that are not specifically excluded from that application.
6 Sampling
The amount of material procured for testing shall be at least 250 g for 1’pe 1, or 500 g for Type 2, and from one batch, and one packet where possible. This material shall be obtained on the open market unannounced and thus taken randomly from stock.
7 Test methods — General
7.1 Ambient temperature
Unless otherwise specified in this document, all test piece preparation and testing shall be conducted at an ambient temperature of (23 ± 2) °C. Where necessary and appropriate, all material shall be allowed to equilibrate at this ambient temperature before testing for at least 24 h.
7.2 Apparatus function verification
All accessories, instruments and equipment shall be examined before use to ensure that they are in acceptable working order, appropriately calibrated, and complying with specifications stated for them in this document, as appropriate.
8 Test methods — Specific
8.1 Visual inspection
Carry out the inspection at an Illuminance of at least 1000 lux and at a distance not exceeding 250 mm. A person making the inspection shall have nominally normal visual acuity. Corrective (non-magnifying) untinted lenses may be worn.
8.2 Flow
8.2.1 Principle
The relative change in length of the test piece under a given load in a specified time is taken as a proxy for the inverse of viscosity.
8.2.2 Apparatus
8.2.2.1 Micrometer screw gauge
Micrometer screw gauge with a range o at least 10 mm, being readable and accurate to 0,005 mm or better, equipped with flat, parallel anvils at least 6.5 mm in diameter and a non-rotating spindle.
NOTE Avoidance of indentation of the wax test piece is essential.
8.2.2.2 Flow-testing instrument
A flow-testing instrument, such as the one shown in Figure 1. consisting of the following components:
— weight (see Figure 1. Key 1);
— shaft, which can move freely in its supports, lubricated as necessary (see Figure 1. Key 2);
— upper platen, metallic, minimum diameter 50 mm, lower surface flat and smooth, rigidly attached and normal to the axis of the shaft (see Figure 1. Key 3);
— base plate, metallic, flat smooth and parallel to the lower surface of the upper platen (Figure L Key 4);
— measuring dial gauge or similarly functional Instrument, with a range of at least 10 mm, readable and accurate to 0,005 mm or better, and rigidly supported (optional) (see Figure 1. Key 5);
— locking screw or equivalent device (required if the dial gauge is used) (see Figure 1. Key 6).ISO 15854 pdf download.