Furniture odor source analysis and control technology

Authors: Liu Ru, Huang Anmin, Wang Chen, and Lü Bin

Unit: Research Institute of Wood Industry, Chinese Academy of Forestry

Funded project: "Research on the testing and evaluation technology of health and safety performance of wooden household materials" (2016YFD0600706), a key R&D project of the 13th Five-Year Plan "Energy Saving and Consumption Reduction and Production Safety Control Technology in the Wood Industry".

Introduction

As custom furniture becomes increasingly popular, the issue of odor is receiving increasing attention. This article reviews the research progress on wood furniture odor, including its sources, influencing factors, detection methods, and control technologies. It also offers suggestions for future research directions.

Wood materials often emit odors, especially in custom furniture, which is particularly problematic due to the large amount of wood used and its immovable nature. According to my market research, in recent years, as many as 1% of custom furniture companies have received customer complaints due to odor issues. While odor perception varies from person to person, and not all odors are harmful, some unpleasant odors can be unpleasant and even cause sensory discomfort and other serious symptoms. Addressing the odor problem in wooden furniture can positively impact the indoor environment.

In view of this, the author analyzes the odor sources, influencing factors, detection methods and control technologies of wooden furniture materials, providing a basis for correctly guiding consumers to understand the odor problem of furniture and building a healthy and safe indoor environment.

1. Odor sources and influencing factors

1.1 Origin of the odor

Almost all wooden furniture, including solid wood and panel furniture, produces odors. Sources of odor include the wood itself, surface coatings, adhesives, decorative materials, edge banding, additives, and packaging materials, which produce volatile organic compounds (VOCs) such as alcohols, aldehydes, ketones, esters, ethers, aromatic hydrocarbons, terpenes, and amines.

1) The wood itself; 2) Surface coating materials; 3) Adhesives; 4) Veneer decorative materials; 5) Edge banding; 6) Additives; 7) Packaging materials; 8) Other materials In addition to the above materials, other auxiliary materials are also used in furniture.

1.2 Factors affecting odor

The smell of wooden furniture materials is not only related to the wood species and board structure, but also affected by factors such as temperature, relative humidity, air flow rate, light and storage environment.

1) Tree species; 2) Board structure; 3) Temperature; 4) Relative humidity; 5) Air velocity; 6) Light; 7) Storage environment;

2 Odor detection methods and control technologies

2.1 Classification of odor detection methods

At present, the odor detection methods mainly include subjective evaluation method and objective evaluation method. Although these two methods can be used to judge the odor of wood materials, they also have certain limitations.

1) Subjective evaluation method

That is, the olfactory method, which is currently a relatively recognized odor detection method both at home and abroad.

The olfactory method can quickly identify a sample's odor, but it requires a high level of expertise from the tester. The tester's understanding of odor types, familiarity with them, and individual factors can significantly influence the test results. Therefore, the tester should undergo systematic training and assessment. They should not have olfactory deficiencies, be heavy smokers, or use heavily scented cosmetics. Regular olfactory comparisons should also be conducted among the testers.

2) Objective evaluation method

The objective evaluation of VOC odors is performed using scientific instruments to qualitatively and quantitatively analyze odor-producing VOC gases. Currently available objective evaluation methods for VOC odors include headspace gas chromatography-mass spectrometry and electronic nose technology.

Objective evaluation methods are relatively accurate in identifying and assessing VOC gases, but they are less effective for certain odors and those resulting from the combined effects of multiple gases. Furthermore, studies have found that high VOC concentrations in gas chromatography-mass spectrometry are not necessarily when odors are most intense. Furthermore, objective evaluation methods cannot distinguish between "benign" and "malicious" odors from wood materials.

2.2 Evaluation procedures of relevant foreign organizations

At present, relevant organizations abroad have evaluated the VOC release and odor of furniture and wood products, including the German Building Products Health Evaluation Committee AgBB, the Finnish Indoor Air Quality and Climate Institute FiSIAQ, the Danish Ministry of Housing and Urban Works ICL, and the international environmental organization Natureplus.

2.3 Odor control technology

Based on the sources and influencing factors of the odor of wooden furniture materials, the author believes that odor control can be carried out from the following aspects.

1) Control the source of the odor of wood materials.

2) Process control of wood-based panel production.

3) Prolong the odor release time of semi-finished and finished products.

4) Environmental control during product use.

5) Develop other odor control technologies.

Conclusion

Although researchers at home and abroad have begun to study the odor of wood materials, there are still some shortcomings:

1) The source and mechanism of odor in wood materials are not yet fully understood, and the relationship between wood materials and VOC gases (concentration, interaction, etc.) has not yet been determined; 2) The odor evaluation of wood materials still mainly relies on subjective evaluation methods; 3) Control technologies are mostly concentrated in corporate environmental control, and odor control technology needs to be improved; 4) There are no domestic testing standards for the odor of wood furniture materials.

In the future, further in-depth research on odor mechanisms, evaluation methods, and control technologies is needed. In addition to the subjective evaluation method to quickly judge the odor level of wood materials, instrumental analysis methods can also be used to assist in qualitative and quantitative final judgments to more comprehensively understand the odor; improve the control technology of wooden furniture materials, and accelerate the formulation of relevant standards to enhance the environmental quality of products and promote the health and safety of indoor environments.