# Vent for gas in ceiling duct

#### DaleRCL

Good Evening All,

We have a gas pipe running through a ceiling duct. The duct is 0.3m x 6.0m so to my calculations, the duct has a cross sectional area of 1.8m2. This means that we need to install a vent with a minimum of 0.05m2 of free area. (Please correct me if you believe that any of the above is incorrect.)

My problem is, is that I can not seem to find anywhere online a vent that comes close to having this amount of free area.

I would welcome any advice on where I could purchase such a vent or on whether I have miscalculated in the first instance.

N

#### Newboy

The duct is 0.3m x 6.0m

That sounds like a rather large duct - is this a void above a ceiling or a huge duct?!

The cross sectional area is width x height - are the figures you've given correct? (is the 6m quoted actually the length?)

#### DaleRCL

Hi Newboy,

Yes, you are right, it is a void above a ceiling. The void is 0.3m high and the room is 6m wide. It is not a purpose made duct, just a dropped ceiling.