Survey (MIPSGAL)                                      24 $\mu$m                     $\sim$6            @carey05    
  [*Spitzer*]{} Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE)            3.6–8.0 $\mu$m                  $\sim$2           @benjamin03  

Results {#sec:data}
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Wide-scale view around W33: environment and H[ii]{} regions {#subsec:radio}
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Figure \[fig1\]a exhibits the spatial distribution of 88 ATLASGAL clumps (having d $\sim$2.6 kpc and V$_\mathrm{lsr}$ range $\sim$\[30, 56\] km s$^{-1}$) overlaid on the ATLASGAL continuum map at 870 $\mu$m, illustrating an extended physical system as mentioned earlier. Figure \[fig1\]b shows the overlay of the NVSS radio continuum emission contours on the MIPSGAL 24 $\mu$m image, revealing the locations of H[ii]{} regions in our selected system. The NVSS 1.4 GHz radio continuum data suggest the presence of the ionized gas, while the warm dust emission is traced in the 24 $\mu$m image. Additionally, one can also find the absorption features against the Galactic background in the 24 $\mu$m image, revealing the IRDCs (see arrows in Figure \[fig1\]b). The locations of previously identified at least three O4-7(super)-giant stars [see IDs \#7, 8, and 23; from @messineo15] are marked in Figures \[fig1\]a and \[fig1\]b (see filled stars). With the application of the [*clumpfind*]{} IDL program [@williams94] in the NVSS 1.4 GHz radio continuum map, we have selected 11 ionized clumps in 