Preferred environmental data
Altitude. Reactions to altitude (headache, nausea, vomiting, palpitation, dizziness…) vary from person to person. Some people can experience symptoms as early as 2,500 m (8,200 ft) but symptoms appears from 4,000 m (13,000 ft) for the majority of people.
CO2 level. Indoor CO2 is best at around 600 ~ 1,000 ppm.
Humidity. Humidity indoors is best between 40% and 60%.
Light intensity. The recommended light intensity may differ depending on the room, the activity and the desired atmosphere. It must be adapted according to your needs.
- Intimate, softened ambience (living room, bedroom…): 25 ~ 50 lux
- Pleasant ambience (living room, kitchen, bedroom, office): 100 ~ 150 lux
- Working condition (office, bedroom, library…): 200 ~ 250 lux
- Technical activity (office, workshop…): 350 ~ 500 lux
Sound / Noise. The harm caused by noise depends on both the volume (level) of noise (dBA) and the duration of exposure.
- 0 dBA ~ 70 dBA: noise level is relatively not harmful.
- 70 dBA ~ 140 dBA: noise level is harmful. People must be careful of the duration of exposure and the intensity. 140 dBA is the threshold of pain.
Note: The exposure limit to noise in office or public venues is often regulated by law. In the US, the permissible exposure limit is is 90 dBA defined by the Department of Labor (OSHA) for all workers for an 8 hour day. For each increase of 5 dBA, the amount of time a person can be exposed is cut by half. For example, at 100 dBA sound level, the permissible exposure limit is 2 hours.
Temperature. Indoor temperature is best between 18°C ~ 21°C or 65°F ~ 70°F.
TVOC level. The level of TVOC must be kept as low as possible at all times. Daily exposure to TVOC levels as low as 40 ppb caused asthma to children. The World Health Organization recommends a concentration of formaldehyde of 0.1 mg/m3 (1 ppb) for 30 minutes. Learn more in WHO Guidelines for Indoor Air Quality.
Note: The preferred environmental data mentioned above is to be taken as recommendations only. Each preferred value should be adapted to your specific situation.