What would be the best way to have individual hanging dust particle show up in the light.

What would be the best way to have individual hanging dust particle show up in the light.

Currently in my scene there is 1 large rect light shinning down on the scene like a spot light.

I have a niaggara system of dust smoke indoors

Then there is an other spot light shinning through the rect light. This light is used to see the dust smoke niagara effect.

I would need the particle dusts being visible from the rect light.

Here is a link of what i am trying to acheive

https://www.google.com/imgres?imgurl=https%3A%2F%2Fi1.sndcdn.com%2Fartworks-000098067923-xzn9qj-t500x500.jpg&tbnid=GLSFqIiFp6mzMM&vet=10CB0QxiAoB2oXChMIkJatwZu6hAMVAAAAAB0AAAAAEAc..i&imgrefurl=https%3A%2F%2Fsoundcloud.com%2Flow-light-mixes%2Fdust-particles-in-sunlight&docid=zC2xRjdMGKtTjM&w=500&h=500&itg=1&q=dust%20in%20light&ved=0CB0QxiAoB2oXChMIkJatwZu6hAMVAAAAAB0AAAAAEAc