Health-related test values for ventilation in schools and childcare centers

The Municipal Health Services' LCM, established in 2006, has radically changed in 2006 the assessment of ventilation in schools and childcare centers by focusing on reducing health risks and improving learning performance instead of simply limiting odor nuisance.
These health-based assessment values from 2006, which are linked to NEN 13779, place CO2 at the center as the essential indicator of indoor air quality. These strict standards are necessary because the air in learning centers is heavily contaminated with pathogens, allergens, and particulate matter, leading to health problems and negatively impacting learning processes. The Municipal Health Service (GGD) classification, which extends the target values of the NEN standard with a "very good" Class 0, has the following core values:

Ventilation class CO2 content including background of 400 ppm (ppm) Fresh air flow per person (m3 per hour)
0. Very good <650 >90
I. Good 650-800 54-90
II. Moderate 800-1000 36-54
III. Inadequate 1000-1400 22-36
IV. Poor >1400 <22

The target value for new buildings is Class 0 (<650 ppm) and for existing buildings Class I (650-800 ppm).

The CO2 concentration is assessed based on the 98th percentile of a five-day measurement at head height. The underlying principle translates the measurements directly into industrial action: at values between 1000 ppm and 1400 ppm (Temporarily Acceptable), measures must be taken as quickly as possible. Above 1400 ppm (Unacceptable), immediate measures must be taken.
The amount required for these strict standards is confirmed by science: more intensive ventilation leads to a lower risk of infectious diseases and to successful cognitive performance. Jille Kuipers, Innovation Manager at LuxBalance, on the GGD standards:
"The GGD test is the standard for learning centers and childcare centers. It makes it clear that an odor-free space is not necessarily a healthy space. Achieving Class I, with a CO2 level below 800 ppm, helps to reduce absenteeism and improve cognitive function. Our job is to develop the tools to not only measure that 800 ppm, but to take immediate action based on the data. The five-day head-height measurement, as conventionally used by the GGD, is the basis for our advice to schools on the optimal placement of their monitors." 
The extensive monitoring and implementation of measures based on CO2 values are suitable for a healthy indoor environment and an optimal learning environment. The accuracy and flexibility of flexible CO2 monitors like the RoomYou1 are crucial to be able to perform measurements in accordance with GGD requirements.

Reference

National Center for Medical Environmental Science for the Dutch Municipal Health Service (GGD). (2006, April 10). Health-based test values for ventilation in schools and childcare centers [Position].