air quality and air quality meters

see also:

• photography and camping main index page
• can excessive farting in a fully enclosed tent cause harm?
• how long does it take to die sleeping in a fully sealed tent or swag?

• air quality is a critical factor in short term and long term health and can particularly impact campers in various ways - usually via camp fire smoke

• there are a wide range of lithium battery powered portable air quality meters available and each have their pros and cons
• some will require a lot of power to run them such that their batteries run out within a couple of hours of use - most, other than just carbon monoxide or smoke detectors, will need to be connected to a USB power bank to run for long periods as they tend to use at least 0.9-1W
• others will alarm unnecessarily when they detect camp fire smoke which can be problematic resulting in the need to turn them off
• what they will detect will vary between models but many have the following or at least some of these:
  • carbon monoxide level
    • should also have a separate conventional carbon monoxide alarm and smoke alarm if at risk of a fire or carbon monoxide poisoning - the silent camp killer
  • carbon dioxide level
    • only really needed in poorly ventilated situations enclosed by non-breathable materials (eg. anything waterproofed) without venting - see how long does it take to die sleeping in a fully sealed tent or swag?
  • particulate matter
    • this is the dangerous stuff that can cause long term harm and when camping is mainly from camp fire smoke, cooking fumes in enclosed spaces, vehicle exhausts
    • true HEPA filters are rated to trap 99.97% of particles that are 0.3 micrometres (µm) in size
    • these cannot pass through waterproofed tent fabrics but will pass through No-See-Um mesh which has holes 600-1000 microns in size
    • even without mesh or air gaps, wind pressure will generally result in air including PM to pass through zipper tracks, seams, etc so you can assume the air quality inside a tent will be similar to that outside in terms of PM (although could be higher if you have a source inside the tent such as a wood stove)
    • PM10 - 10microns or smaller
      • these generally get trapped by the hairs and mucus in your nose and throat
    • PM2.5 - 2.5microns or smaller
      • these are so small that they can pass through to the lungs exacerbating asthma and can be absorbed into the lymphatics and blood stream causing systemic inflammation
      • clean air has levels below 12μg/m³
      • levels up to 35μg/m³ are acceptable for short exposures but for 24 hour exposures, levels should average below 15-25μg/m³
      • average exposure over a year should be below 5μg/m³
    • PM1.0 - 1micron or smaller
      • mainly generated by fresh smoke (soot) from wood stoves, wildfires, or diesel exhaust engines
      • includes atmospheric smog particles
      • many airborne bacteria and large viral droplets float around the 0.5 to 1.0-micron range
      • the hardest size for a HEPA filter to catch is 0.3 microns — known as the Most Penetrating Particle Size (MPPS)
  • volatiles:
    • HCHO (formaldehyde)
      • a carcinogen, mainly from off-gassing from MDF wood, plywood, particle board, glues, paints, varnishes, tobacco smoke, exhausts, burning organic matter
      • max safe levels are usually put at 0.12 mg/m³ (0.1ppm)
    • TVOC (Total Volatile Organic Compounds)
      • includes benzene, toluene, ethanol, acetone, HCHO, solvents such as cyclohexanone and n-butyl acetate (frequently used in vinyl flooring), 2-ethyl-1-hexanol (2E1H), which off-gas heavily from vinyl wallpapers and flooring, plasticizers & texturisers such as TXIB (2,2,4-trimethyl-1,3-pentanediol diisobutyrate)
      • also includes primary emissions off-gassing from PVC but not the less volatile slow off-gassing phthalates which tend to stick to surfaces and dust rather than floating as a gas
      • usually from household cleaners, disinfectants, paints, aerosol sprays, new carpets, cosmetics, air fresheners
      • max safe levels are usually put at 0.5-1.0 mg/m³ (0.5-1ppm)
      • standard HEPA filters do not trap gases such as VOCs as these need to be chemically trapped such as with a heavy activated carbon pellet filter
  • temperature and humidity
    • these can significantly adversely affect your health and sleep
    • air temperature should ideally be between 18-21degC for sleeping
    • higher temperatures make sleeping more difficult
    • high humidity exaggerates the effects of both low and high temperatures and can also result in PM-saturated smog when fog combines with camp fire smoke
    • WHO indicates that temperatures below 18degC whilst sleeping increases blood pressure
    • temperatures below ~12degC will cause cold bronchospasm, coughing and potentially severe asthma attacks in those who are susceptible
    • see keeping warm when camping or hiking