BS ISO 16000-28:2020 pdf download – Indoor air Part 28: Determination of odour emissions from building products using test chambers
The standard procedure for odour assessment is carried out by using sample containers (see 6.3.3). Alternatively, direct assessment from the outlet of the emission test chamber is possible if sufficient air flow is assured (see 6.3.1).In this case the outlet shall be fitted with a funnel.
NOTE Due to the requirements of 6.3.1 sufficient air flow is only possible if the following requirements are met: test chambers with more than 4,3 m 3 volume at 0,5 h −1 air change rate. If the odour assessment is carried out directly from the outlet of the chamber, the chamber material shall be non‑transparent, or the chamber shall be covered in order to avoid the panel members being influenced by visual recognition of the material in test. The test room in which the sensory assessment is performed shall conform with the general requirements described in 7.2. The panel members shall not be influenced by the working environment (light, acoustics, background odours).
6.2 Test room and recovery room The test room and the recovery room shall be odour neutral, sufficiently large and unobtrusively designed. Contamination of the room air by any source, e.g. by coatings, wall and floor coverings, furniture, shall be prevented. In preparation for sensory testing, the air in the test room and the recovery room shall be assessed for acceptability or perceived intensity (7.2.1), and the requirements set out in 7.2.2–7.2.4 shall be complied with.
6.3 Odour sampling and assessment devices
6.3.1 General The odour sampling and assessment devices shall ensure that
— the air flow is sufficient to guarantee that the panel members inhale only sample air during the assessment, and
— significant adsorption on the surfaces is avoided and the interface has no emissions of its own to interfere with the sample air.
6.3.2 Funnel The odour evaluation interface consists of a funnel, which is connected to the outlet of the sample presentation system or to the outlet of the emission test chamber. The funnel and the inner surfaces of the connection ducting shall be composed of glass or surface‑treated (polished) stainless steel. The air flow at the outlet from the funnel to the panel member shall be between 0,6 l/s to 1 l/s and shall be constant for the duration of each test session. The design of the measurement funnel ensures that no ambient air is sucked in and mixed with the sample air. An opening angle (both sides) of up to 12° ensures a homogeneous outflow of sample air (see Figure 1). To prevent contamination of the test room air, the excess air flow shall be extracted above the funnel.
6.3.3 Sample containers
The following materials are suitable to be used as a sample container:
— polyethylene terephthalate (PET, Nalophane® 1) );
— polyvinyl fluoride (PVF, Tedlar® 2) ).
All batches of container material shall be evaluated for unusual emissions/bachground odours before first use. PVF/Tedlar® containers need to be conditioned before first use, see 8.4 and Annex C.
Sample containers made of PET shall not be reused.
Other container materials may be used if the performance is tested according to Annex C.
6.3.4 Sample presentation system
A sample presentation system is a device designed for providing odour samples from the sample containers to the interface (funnel) for odour testing. The size of the sample presentation system is based on the size of the sample containers. The system shall be designed to minimise influence on the odour samples and test room conditions. Any parts in direct contact with the odour sample shall be made from glass, polished stainless steel or polytetrafluoroethylene (PTFE).
NOTE For an example of a suitable sample presentation system see Annex C.
6.4 Comparative scale
A comparative scale offers at least six different reference stimuli by means of presentation funnels. BS ISO 16000-28 pdf download.