A comparative study of some methods for measuring carbon monoxide in air.

The present study aimed at comparing between some physical and chemical methods for measuring carbon monoxide (CO) level in air and selecting the most suitable one concerning simplicity, reproducibility, sensitivity, specificity, and accuracy. Known concentrations of CO were prepared in cylinders and air samples with unknown concentrations of CO were collected in plastic bags from the street environment. Both known and unknown concentrations of CO were measured by four selected methods. The leucocrystal violet method was found suitable only for levels of CO higher than 40 ppm and not recommended for ambient levels. The iodine pentoxide method was suitable for any level of CO in air but only for grab samples. The combustion method was also suitable for any level of CO above 10 ppm and for grab and continuous samples. MIRAN-IA analyzer is an infrared instrument, is very simple, sensitive and accurate for concentrations of 10 ppm and above. Other types of infrared analyzers may give higher accuracy and sensitivity levels at lower concentrations.

Dust exposure in manual flax processing in Egypt.

Manual flax processing originated in Egypt in 2 000 BC. In the present study a representative sample of the workers involved in this trade, where flax is processed in small workshops or homes, was examined, and their dust exposure was evaluated. The study showed that workers handling and processing flax are exposed to high concentrations of dust; the levels of dust at hackling and combing are considerably higher than at batting and spinning. Byssinosis prevailed in 22-9% of the examined workers, and 18-4% of them had their forced expiratory volume in one second reduced by more than 10% at the end of the first morning work period (4 hours) of the week. Both the rates and the grades of these syndromes increased with duration of exposure. Smoking appeared to be one of the important contributory factors in the production of byssinosis. The relationship between dust concentration and prevalence of byssinosis seems to be curvilinear.

Study of some parameters affecting noise level in textile spinning and weaving mills.

Noise was evaluated in six spinning and five weaving halls located in three textile mills in Egypt. Spindle speed (rpm) and loom speed (picks per minutes) were found to be important parameters affecting the noise level in these mills. Reduction of the number of spinning machines to five spindles per square meter of floor area will probably bring the noise level below the TLV. In the weaving departments, the decrease in the number of looms will not effectively reduce the noise level.