Ventallation, is it really necessary?

This question may be redundant, but I can't nail down a definitive answer.

Like the question before, I am growing in a 4x4X8 room. I'm going to run a 600 watt with about 5 plants. I not as much concerned with the "Aroma" problem as I am with the heat problem.

Its going to be in the basement where the temperatures are always cold. Its near an A/C duct, so I could draw some air IN, but not out.

Before I construct a ventallation project, my question is....

Does a 600watt produce enough heat for a fire hazard in a 4x4x8 room? Thats my main concern. Will it get too unbearably hot in there?

I just always thought ventallation was for the "smell" issue. I never factored in a safety issue.

DO I NEED TO VENT IT FOR HEAT ISSUES?

As always, thanks in advance!

If the 4x4x8 space is always sealed?...yes ...you will need fresh air coming in at the bottom or between the canopy and the light.

A space for the heat to get out, (the top, normally) is needed, too.

Bottomline: Temps need to stay at 75-85 degrees....IMO. Cold can be as bad as hot...especially in winter.

Can you recommend a decent exhaust fan setup?