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Benzene is one of the most harmful VOCs pollutions which its control emission is a vital purpose in industries and environment. A new and efficient method based on solid phase gas extraction (SPGE) with Schiff base immobilized on MWCNTs (TerphApm@MWCNTs) as a novel sorbent was used for benzene removal from artificial air after loaded in Robson quartz tubes (RGT). The TerphApm@MWCNTs were synthesized and purified via heat treatment at 60 °C as a new heterogeneous sorbent. In bench scale set up, a system was designed and developed for standard gas generation of benzene in air with difference concentrations, and then was passed through RGT by SKC pump at optimized flow rate. Benzene volatile was absorbed on the TerphApm@MWCNTs and desorbed from it at 80 °C before determined by GC/FID. The important factors such as, temperature, humidity, benzene concentration, amount of adsorbent and flow rate were optimized. The recovery and capacity of benzene capture with 20 mg of TerphApm@MWCNTs were obtained 98% and 492 mg g−1 (25 °C). The flow rate and temperature had highly impact on the removal efficiency and adsorption capacity. According to results, the unique characterization of TerphApm@MWCNTs can be considered as a best adsorbent for benzene removal from air as compare to MWCNTs, SWCNTs, and NAC. Keywords: Benzene, Adsorption, Air pollutant, Schiff base immobilized on MWCNTs, Solid phase gas extraction

Construction is one of the most hazardous workplaces in all around the world. Awareness about workers’ attitude towards safety could be helpful in anticipating the workers' behavior. The aims of this study were to determine both the tunneling workers' safety attitude and the relationship between workers' attitude towards safety and occupational accidents. In this cross-sectional study performed in eight tunneling projects in Iran in 2013-2014, overall 689 workers of the tunneling projects were selected. One-hundred fifty had experienced at least one occupational accident. Requisite variables of workers were collected via both standardized questionnaire and checklist. The participants were selected randomly with the stratified random sampling. The data were statistically analyzed using logistics regression, multivariate logistic regression and Spearman correlation coefficient where applicable (with a preset probability of (P0.05). Accident experience, as well as education level, could affect positively on changing workers' safety attitude.