What is the procedure for blowing out the ductwork to remove dust before final grilles go on?

1. Keep all expensive, finished architectural registers, diffusers, and grilles completely off the duct branch drops. 2. Leave the ends of the final branch drops open, or cover them with temporary cheesecloth mesh filters to catch construction debris. 3. Turn on the primary supply air handling fan unit to run at a low-to-medium speed setting to sweep all loose metal shavings, sawdust, and jobsite dust out of the internal lines. 4. Shut down the fan, clean out any debris caught in the drops, and

['1. Keep all expensive, finished architectural registers, diffusers, and grilles completely off the duct branch drops. 2. Leave the ends of the final branch drops open, or cover them with temporary cheesecloth mesh filters to catch construction debris. 3. Turn on the primary supply air handling fan unit to run at a low-to-medium speed setting to sweep all loose metal shavings, sawdust, and jobsite dust out of the internal lines. 4. Shut down the fan, clean out any debris caught in the drops, and proceed with final trim finish trim installation.']

Stop if

• Use this as training guidance. The foreman, approved drawings, project specs, manufacturer installation instructions, employer safety policy, and AHJ/code requirements always control the final answer.

Steps

• Keep all expensive, finished architectural registers, diffusers, and grilles completely off the duct branch drops.
• Leave the ends of the final branch drops open, or cover them with temporary cheesecloth mesh filters to catch construction debris.
• Turn on the primary supply air handling fan unit to run at a low-to-medium speed setting to sweep all loose metal shavings, sawdust, and jobsite dust out of the internal lines.
• Shut down the fan, clean out any debris caught in the drops, and proceed with final trim finish trim installation.

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