Intent:
- provide capacity for ventilation system monitoring to sustain occupant comfort and well-being.
Implementation:
- Install Permanent monitoring systems that provide feedback on ventilation system performance
- systems to generate ALARM when conditions vary by 10% set point
- Mechanically vented spaces:
- Densely Monitored Space: > 25 people/1000SF
- monitor CO2 levels
- Monitor location to be 3′ to 6′ above floor finish
- monitor CO2 levels
- for non-densely occupied spaces
- provide direct outdoor airflow measure device.
- detect when system is 15% below design rate
- Densely Monitored Space: > 25 people/1000SF
- Naturally Ventilated Space:
- Monitor CO2
- Monitor location to be 3′ to 6′ above floor finish
- Monitor CO2
- CO2 and airflow measures by:
- pitot tubes, venturi meters, rotating vane anemometers
- feed into HVAC and BAS systems
Code:
- none
Submittal Phase:
- design
Indoor Environmental Air Quality
- EQ P1 – Minimum IAQ Performance (prerequisite )
- EQ P2 – Environmental Tobacco Smoke (ETS) Control (prerequisite )
- EQ 1 – Outdoor Air Delivery Monitoring
- EQ 2 – Increased Ventilation
- EQ 3.1 – Construction IAQ Management Plan, During Construction
- EQ 3.2 – Construction IAQ Management Plan, Before Occupancy
- EQ 4.1 – Low-Emitting Materials, Adhesives & Sealants
- EQ 4.2 – Low-Emitting Materials, Paint & Coatings
- EQ 4.3 – Low-Emitting Materials, Carpet Systems
- EQ 4.4 – Low-Emitting Materials, Composite Wood & Agrifiber Products
- EQ 5 – Indoor Chemical & Pollutant Source Control
- EQ 6.1 – Controllability of Systems, Lighting
- EQ 6.2 – Controllability of Systems, Thermal Comfort
- EQ 7.1 – Thermal Comfort, Design
- EQ 7.2 – Thermal Comfort, Verification
- EQ 8.1 -Daylight & Views, Daylight 75% of Spaces
- EQ 8.2 – Daylight & Views, Views for 90% of Spaces
13 Comments On This Post
for mechanically ventillated spaces, do you not also have to have CO2 detection devices 3 to ft above the floor?
Hi Bill,
Yes – all CO2 detection devices, no matter the location, should always be located between 3′-0″ and 6′-0″ above the floor finish.
I’ll update the info above to make it a little clearer. Thanks Bill!
Best of luck to you!
The air flow is measured by a pitot tube. Not pilot tube. THANKS FOR YOUR SITE TO HELP ME PREPARE FOR THE TEST.
This is a little picky, but the general requirements say “configure all monitoring equipment to generate an alarm when the conditions vary 10% or more from a setpoint.” However, all mention of outdoor airflow monitoring says to have an alarm sound at 15% variance (plus/minus in mechanical non-dense requirements and only “below” in outdoor air flow monitoring). So…are there 2 alarms? Or does the 10% apply to CO2 from mechanical densely-occupied or naturally ventilated spaces?
Guys I take the test this afternoon and this issue katie has is one that i have raised also. I researche dit and it seems that the the Ref. Guide was a little ambiguous about the 10%. But it basically is saying 10%(or more) would be the guide whenever the CO2 monitoring was required. 15% is the standard when using Outdoor Air-Flow Monitoring devices.
See Below.
Monitoring systems that generate an alarm when the conditions vary by 10% or more from a setpoint.
FOR MECHANICALLY VENTILATED SPACES
• Monitor CO2 within all densely occupied spaces (25 people/1000 sq.ft.). Locations shall be between 3 and 6 ft AFF. (10% SHOULD BE ADDED HERE FOR CLARITY)
• For non-densely occupied space equipment, provide a direct outdoor airflow measurement device capable of measuring the minimum outdoor airflow rate with an accuracy of plus or minus 15% of the design minimum outdoor air rate, as defined by ASHRAE 62.1-2004.
I passed, first try! Thanks Pat (in addition to my own hardwork..lol).
If an exam question asks for ‘which credit’ and a prerequisite is one of the answer choices, can I safely assume that the prequisite is not the right answer since it is not a credit?
I’ve seen some practice exams that have a prequisite as the right answer when asking for a ‘credit.’ Thanks.
Do we need all these measuring equipment when our building codes exceed ASHRAE about 6 times concerning the ventilation rate?
Hybrid systems used in Europe don’t have recirculation anymore, just about 1 air change per hour with extensive heat and moisture recovery (>80%/>80%).
Many times even these systems are frequency controlled by occupancy ot CO2 sensors. So a variation of 1% is not achievable. Measuring the air flow in the inlet grille will not representable.
Climatizing is done with radiant ceilings, floors or chilled/heated beams.
At the lower right corner of page 308, Reference Guide, it said “There are two typical system configuration that generally meet the requirements of this credit. One approach utilizes CO2 sensors that use measured concentration to provide an alert.”
What is the second approach/system configuration?
Answering Richard’s Question:
May be the first requirement has to fulfill 1000 ppm of indoor concentration level and the second requirement could be higher than 1000 ppm based on the Standard 62.1-2004.
Any comments on this?
I THINK the other system design that meets the requirement is the outdoor air rate monitors to 15% of min ashrae as discussed above- I think they are presenting the CO2 system configuration with sensors as the second option- does this make sense to you?
The discussion of two approaches are under the co2 monitoring, and the way the text is worded leads me to beleive that
approach 1 – CO2 setpoint at 1000 ppm
approach 2 – CO2 setpoint can be higher when design complies with ASHRAE 62.1, and I guess more information can be obtained from Appendix A.
Can someone please confirm this…
Mechanically ventilated space
Densely occupied space- CO2 sensors
Non- densely occupied- Outdoor airflow montitoring device.
Naturally ventilated spaces- CO2 sensors