Humans ; Occupational Exposure ; prevention & control ; Respiratory Protective Devices ; classification ; standards ; utilization ; United States

OBJECTIVETo develop two new respirator fit test panels using data from anthropometric survey of Chinese adult workers: bivariate panel and principal component analysis (PCA) panel for meeting the requirements of respirator fit design and testing and evaluate the applicability of the two different fit test panels for current Chinese workers.

METHODSAn anthropometric database based upon anthropometric data of current Chinese workers was used for panel design. The bivariate panel was based upon the bivariate distribution of the face length and face width measurements, and the PCA panel was developed using principal components analysis of 10 stable facial dimensions (minimum frontal breadth, face width, bigonial breadth, face length, interpupillary distance, head breadth, nose protrusion, nose breadth, nasal root breadth, subnasale-sellion length). The distribution of Chinese workers across the panels was used to analyze the panels' applicability for Chinese workers.

RESULTSThe bivariate panel and PCA panel developed in this study consisted of 10 cells and 8 cells respectively, covered 96.9% (male 95.4%, female 98.4%) and 96.5% (male 95.1%, female 98.1%) of the current Chinese workers, respectively. The distribution of workers across both panels was uniform. Each cell contained 4.6% - 21.7% of the population in the bivariate panel and 10.4% - 14.6% of the population in the PCA panel. The LANL full-face piece respirator fit test panel covered only 70.9% of the Chinese workers, It was thought to be no longer adequate for the Chinese adult workers.

CONCLUSIONNew respirator fit test panels based on updated anthropometric database and distributions specific to Chinese workers may be more beneficial for applications in China.

Adult ; China ; Equipment Design ; Female ; Humans ; Male ; Principal Component Analysis ; Reference Values ; Respiratory Protective Devices

OBJECTIVETo probe into the physical changes on the head and face of Chinese adults, find the representative indexes and provide references for head-face products design especially in the field of labor protection.

METHODSThe ISO7250-1996 and GB/T5703-99 Basic Human Body Measurements for Technological Design was used. Twenty items of head-face referential parameters and 4 items of body indexes (height, weight, waist circumference and buttock circumference) were measured by using sliding caliper, spreading caliper and pupillometer. The populations were sampled by age, gender and region and their influences on the head and face dimensions were statistically analyzed. By studying the relationship between these parameters with correlation and cluster analysis, the representative indexes of head and face dimensions were concluded.

RESULTS3000 objectives (2026 men and 974 women) were involved in this survey. The results enunciated that the values of the items in male were larger than those in female. For example, the mean values of face length, face width, jaw width, lip length and nose protrusion were 117.0, 147.6, 118.5, 51.7, 18.7 mm for male and 109.7, 140.1, 114.5, 49.3, 17.7 mm for female. The regional disparity and obesity were significant factors. The sizes of head and face of north-eastern population were significantly bigger than those of south-western population except of maximum length of head, the length of lip and face configuration length. The sizes of head and face of obesity population were significantly bigger than those of non-obesity population (P < 0.01). By the cluster analysis, five representative indexes (face length, face width, jaw width, lip length and nose protrusion) were obtained. Further correction analysis suggested that these indexes could well represent the head-face dimensions.

CONCLUSIONThe influence of gender, region and obesity on the head-face dimensions is significant. The age is not a significant influential factor. Five representative indexes (face length, face width, jaw width, lip length and nose protrusion) are obtained to provide foundation in the standard design of head-face products.

Adolescent ; Adult ; Aged ; Asian Continental Ancestry Group ; statistics & numerical data ; Cephalometry ; Cluster Analysis ; Face ; anatomy & histology ; Female ; Head ; anatomy & histology ; Humans ; Jaw ; anatomy & histology ; Lip ; anatomy & histology ; Male ; Middle Aged ; Nose ; anatomy & histology ; Reference Values ; Young Adult