Regarding dust collector requirements:
Several dust hoods located randomly around a 40,000 sf factory. a 4in duct starts from the hood and joins a larger trunk main.
My questions are:
Are sprinklers required in the hood? Under 48in?
Would a control valve drop be required, similar to a paint booth?
Since the duct is only 4in, would a head be required at the top of the stack?
NFPA requires that ducts be protected when more than 75 sq in. This translates down to roughly a 10 in circular duct. If heads are not required at the hood, can a supply be taken from the existing system at the roof? Are there any valving requirements for this arrangement?
Thanks in advance for your quick answer!