| Head and face measurement is an important part of anthropology study. It can be used in the area of anthropology, ethnology, after obtaining the type, characters and physical changes on the head and face through measurement. It is also used in area of forensic medicine, fairing medicine, medical equipment design. Because of the developing of industy, concern has been raised about compatibilityof the respirators. The suitable size not only satisfies the comfort of wearing, but is also the requirement for healthy of the labor.Personal protective equipment (PPE) that is often referred to as the"last line of defense"plays an essential role in protecting those who must work in hazardous environments. According to the 2001 NIOSH-Bureau of Labor Statistics (BLS) survey of respirator use in the private sector in United States, employed at 281,776 establishments (4.5% of total), there are 3,303,414 respirator users (3.1% of total). China has large supplier of labor. Some specialists estimate that there are more than 20,000,000 works with exposure to dust. Though little survey about our respirator use has been conducted, there are many people need them to prevent contaminants. But we also use the LANL panel to determine how respirators fit the general working population. So it can not satify our needing, and it is necessary to establish Chinese respirator fit test panels. As we know, setting up Chinese anthropometric database is the first tast of all.The first collection of head and face anthropometric data occurred in China in 1958. A head-and -face anthropometry survey of 43,173 military personnel was conducted at that time. Then in 1980, a group of researchers from the Beijing Institute of Labor Protection and the Chinese Institute of Science started another head-and-face anthropometric survey of 9392 civilian adults. All data were used to create the Chinese national standard (GB2428-81) published in 1981. In this standard, thirteen head sizes, based on 29 dimensions, were defined for males and females separately. In 1988, a new database of Chinese human dimensions was established from 22,300 adults. The database included 7 basic head-and-face dimensions: full-head length, sagittal arc, bitragion coronal arc, head breath, head length, head circumference and menton-sellion length (face length). In 1998, a survey of 393 Chinese adults was conducted by Xiao et al, on 41 head-and-face dimensions, to understand the relationship between different dimensions. Then, relationships (regression equations) between the 41 new dimensions and the 7 dimensions from the 1988 Chinese database were established and used to create the Chinese national standard of head-face dimensions for adults (GB/T2428-1998).There are differences in different countries and regions about anthropometric dimeansion. Besides, it is not identical between different periods just in the same region. In China, height and weight of the population have changed greatly in the last 20 years because of the increase of economy and nutriture. The average height of young people (12-18 years old) has increased 2cm and weight 3Kg per ten years. It is shown that the height of Italian height was linear increace in the last 300 years. According to the change characters, anthropometric measurement should be conducted repeatly after some days, even though in the same countries or region.In order to understand the physical changes on the head and face of Chinese adults, supplement the Chinese anthropometric database and construct the respiration fit test panel fitting to our countries, this paper consisted of two parts will be described. In the first part, 3000 objectives were involved in this survey consisted of different region of birth strata, different age strata, different gender strata. Head-face dimeansions were measured by using sliding caliper,spreading caliper and pupillometer and the Chinese anthropometric database were obtained. The factors were analyzed which relate to, or may influence the head-and-face dimensions. Five representative indexes were to be found through statistical analysis. In the second part, the database was used to develop new respirator fit test panels specific to the Chinese civilian population using the bivariate distribution of face length and face width approach.Part I: The measurement of human head-Face dimensionsAdopting ISO7250《Basic human body measurements for technological design》and GB/T5703-1999《Basic human body measurements for technological design》, 3000 objectives consisted of different region of birth strata and different age strata were measured by using sliding caliper,spreading caliper and pupillometer in this survey. And the influences on the head and face dimensions were statistically analyzed. The results enunciated that the values of the items in male were larger than those in female. The regional disparity was a significant factor. The head-face sizes of Northern China were bigger than Southern China except head length, lip length and face length. And obesity was also a significant factor. But age was not a significant factor. In comparison with the facial dimensions of others, lip length, face width and bigonial breadth (jaw width) for both genders in this study are elevated these years. When compared with facial anthropometric dimensions of the US survey in 2003, we found that the mean values of lip length and face width for all Chinese subjects are significantly larger than those of the 2003 NIOSH survey (p < 0.05). By the correlation and cluster analysis, the dimensions were classified and 5 representative indexes (face length, face width, jaw width, lip length and nose protrusion) were selected to represent the head-face dimensions.Part II: Chinese respirator fit test panelThe database was used to develop new respirator fit test panel specific to the Chinese civilian population using the bivariate distribution of face length and face width approach, the distribution of survey subjects within the bivariate panel and the frame of Chinese panel construction. From the result, we found that the range of the LANL panel just included of 70.9%. While using the NIOSH panel, there were not a consistent number of subjects throughout the cells. 52.8% of the population falled into two cells, while not more than 1% of the population falled into two cells. The Chinese bivariate panel developed had limits of 96 mm to 132 mm for face length and 128.5 to 158.5 mm for face width at last. This panel covered 96.9% civilian workforce. The distribution of survey subjects within the Chinese bivariate panel was now uniform and each cell contained at least 4.6% of the population. Then we can get the guide in the standard design and the number of head-face products according to the database. It will provide foundation to formulate Chinese national standard in head-face dimensions, labor protection and ergonomics design. Conclusions:1 In comparison with the facial dimensions of the Chinese national standard published in 1981 and 1998, lip length, face width and bigonial breadth (jaw width) for both genders in this study were elevated. The face length of male subjects in this study was smaller than Chinese national standard. The mean value of nose protrusion for females was larger than that of national standard. The face length of females and nose protrusion of males in this study were between national standard values of 1981 and 1998.2 When compared with facial anthropometric dimensions of the US survey (Zhuang and Bradtmiller, 2005), we found that the mean values of lip length and face width for all Chinese subjects were significantly larger than those of the 2003 NIOSH survey. However, the mean values of face length and nose protrusion for both genders in this study were significantly smaller than those of the NIOSH survey. Chinese face was shorter but wider than American.3 Head-and-face anthropometric dimensions were influenced by many factors including, age, race, region of birth, and perhaps other factors. Gender and body type were significant factors after analyzing. The results enunciated that the values of the items in male were larger than those in female. And obesity was also a significant factor. But the influence of age was not significant. The results indicated that anthropometric dimensions of construction workers and miners tended to be below the average over all industries, but health care workers and workers in the manufacturing industry were above the overall industry average.4 By the cluster analysis, 5 representative indexes were selected to represent the head-face dimensions. They were face length, face width, jaw width, lip length and nose protrusion. The mean values were 117.0mm, 147.6mm, 118.5mm, 51.7mm, 18.7mm for male and 109.7mm, 140.1mm, 114.5mm, 49.3mm, 17.7mm for female.5 The Chinese bivariate panel developed had limits of 96 mm to 132 mm for face length and 128.5 to 158.5 mm for face width at last. 10 types were obtained and this panel covered 96.9% civilian workforce. The distribution of survey subjects within the Chinese bivariate panel was now uniform and each cell contained at least 4.6% of the population.
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