The ρeff were 0.89, 0.58, and 0.51 g/cm3 for conventional diesel and 0.90, 0.62, and 0.42 g/cm3 for PCCI particles with 50, 100, and 150 nm electrical mobility diameters (dm), respectively. 

Thanks sir, could you please tell me the standard name and number of this information?

Thanks

The WHO air quality guidelines (AQGs) are intended for worldwide use but have been developed to support actions to achieve air quality that protects public health in different contexts. Air quality standards, on the other hand, are set by each country to protect the public health of their citizens and as such are an important component of national risk management and environmental policies. National standards will vary according to the approach adopted for balancing health risks, technological feasibility, economic considerations and various other political and social factors, which in turn will depend on, among other things, the level of development and national capability in air quality management. The guideline values recommended by WHO acknowledge this heterogeneity and, in particular, recognize that when formulating policy targets, governments should consider their own local circumstances carefully before adopting the guidelines directly as legally based standards.

Guidelines

PM2.5: 10 µg/m3 annual mean

25 µg/m3 24-hour mean

PM10: 20 µg/m3 annual mean

50 µg/m3 24-hour mean

http://apps.who.int/iris/bitstream/10665/69477/1/WHO_SDE_PHE_OEH_06.02_eng.pdf

Thanks sir for the pdf, but to be comfortable with the numbers, suppose that I have 80 mg/m^3 soot density in a room, how can we know if this is toxic or not ? I mean, what is the deadly limit of the soot like Mr. Prakhar, he typed the deadly limits in mg/m^3...I compared my nuber with his limits and I found it is not deadly, also, the CO concentration is very low and it is not 3000 ppm (deadly limit)..Thanks