camp fires and fire restrictions

see also:

• wood stoves for camping
• gas or liquid fuel stoves for camping
• risk management when camping
• photography and camping main index page

• CFA Fire Danger Restriction periods for Victorian municipalities
• Victorian restrictions during Fire Danger Periods and Total Fire Ban days

• camping with an open fire is a traditional activity that harks back to the days of cave dwellers as an essential survival technique and perhaps that is why so many are attracted to the ambience and the social gathering aspects as well as just chilling out in front of the warmth while you watch the Milky Way
• from April to Sept, the nights are long and cold in the southern states, by early April after Daylight Savings has ended, the sun sets around 6pm and this gets earlier as the days progress - a wood fire becomes an important source of warmth and light to those who wish to stay up and socialise
• as much as it is loved, it can be problematic and dangerous
• if there are no fire pits, please respect the environment and do not create new ones unless in an emergency
  • there are ways to reduce fire scars such as portable, elevated fire pits but even these can kill nearby vegetation

• you MUST understand in detail the local laws and regulations regarding camp fires
  • see Victorian rules on camp fires
• you MUST bring adequate water to be able to completely put the fire out
  • bring lots of extra water (~10-20L on hand)
• you may have to bring your own wood or order it to be delivered by locals
  • dead branches and trees are important parts of the environment to allow many animals to survive
  • if collecting wood is permitted, you may need an axe and chainsaw!
    • watch out for snakes when collecting wood - snakes often sleep in or under wood and will think you are attacking them.
  • for a group camp fire, the fire needs to be big enough to keep everyone warm so aim for 10kg firewood per person per night (if the fire is too small, people will tend to get too close, stand around it and create fire hazard/burns risk)
  • a small axe will be useful for chopping kindling
  • a Canadian wood splitter axe will be useful to split large log segments
  • see bushcraft and camping axes
• you are going to create fire and smoke - think well before you do so
  • don't light a fire in a valley on a night with no wind when it is likely to become foggy - the smoke will just settle around your camp sites and you will have extremely poor air quality to try to breathe all night!
  • check the wind direction and likely changes so the smoke does not blow into your tent or others
    • in general, if there is some wind, it is best to position the fire and your shelter so that the wind blows from the side rather than in line with your shelter-fire axis
      • if you have the wind coming from behind your shelter to blow the smoke away from the shelter, this is likely not to work as well as you think as your shelter will create turbulence for the air hitting the fire and it may actually travel back into the shelter
    • if there is minimal wind, the smoke will generally blow towards the tallest nearby object - that is probably going to be you or your shelter
      • you can help mitigate this by creating a taller object on the other side of the fire
  • bring your “sitting around fire” clothing:
    • your clothing will become smokey and remain so until washed
    • avoid light flammable clothing near the fire - 3rd degree burns may be the result
    • don't get drunk - you may trip and fall into the fire
• bring cooking options
  • don't forget aluminium foil!
• don't forget to bring chairs!
• bring burns first aid
  • unlike hot water scalds, fires will generally cause full thickness 3rd degree burns which usually need skin grafts - prevention is always best!
  • Glad Wrap is excellent for large severe burns until you can get to a hospital
• have a responsible person manage fire safety including trip hazards!
  • a long handled shovel works well for managing the coals and burning wood
• consider lip balm as your lips are likely to dry out and chap from prolonged radiant heat exposure and this may then cause an outbreak of cold sores
• consider a small fire extinguisher and fire blanket

• When heated, wood undergoes thermal degradation and combustion to produce gases, vapours, levoglucosan tars and carbonaceous char
  • hemicellulose decomposes first at 180 – 350°C
  • followed by cellulose (275 – 350°C)
  • then lignin (250 – 500°C)
  • Cross-linking reactions dehydrate cellulose and the re-polymerized levoglucosan begin to yield aromatic structures, becoming graphitic carbon structures at around 500°C. This decomposition process is termed pyrolysis.
  • the charred surface of wood can have temperatures of 800°C, the main pyrolysis of wood begins at temperatures above 225°C and ends below 500°C
  • When an appropriate volatile fuel-air concentration has been reached, oxidation of the pyrolysis gases leads to flaming combustion
  • in contrast, oxidation of the remaining char produces glowing or smouldering combustion
  • Smoke production depends on the burning material, oxygen supply and type of combustion (e.g. flaming or glowing).
  • at low burn temperatures, more smoke, tars and char is produced (hence not good for wood stoves to burn at low temperatures as creosote will build up more readily in the chimney)
• provided the whole of the log is involved, the rate of mass loss during combustion is constant
• around 60-80% is converted to convective heat and the remainder as radiant heat
• most Australian woods give the same energy output of around 17MJ/kg (air-dried pine is less dense than air dried eucalypt hard woods so you need more to get the same mass in kg)
• a wood log burns by:
  • flaming combustion
  • and glowing combustion (those lovely ashes in your camp fire)
• the proportion of flaming combustion decreases with log diameter
  • 45% for oven-dried jarrah 65-75mm diameter
• forest logs:
  • log burn time in minutes (assuming whole log is burning) = 1.3 x 10⁴ x log radius in metres^1.686 for logs < 12.5 cm (larger diameter logs have higher moisture rates and tend not to maintain flaming combustion ⁴⁾
    • ie. a 10cm diameter log, if all of it is burning, will burn for about 80 minutes, whereas a 5cm diameter log (eg. larger kindling) will burn for about 25 minutes
    • hence you will need to replenish small wood in a camp wood stove every 25-45 minutes depending upon the diameter of each bit of wood used

• many camp grounds do have fire pits and generally ban you from having fires on the ground not in a designated fire pit
• these often have a metal base which prevents heat warming your feet and they also limit the size of the fire so it will only warm a small group

• these are favoured by large groups up to a maximum of around 30 people as the fire can be made larger so people can remain warm enough further back in a ring
• unfortunately they are not great for the environment and obviously leave fire scars

• used by the Dakota people on windy grass plains to reduce risk of grass fires and reduce smoke
• dig two holes in the ground and connect with a tunnel which will provide air to the fire which is lit in the larger hole
• only works on rich, firm soil not on frozen or sandy soils
• only for keeping a small group warm and for cooking

• these enable one to elevate the fire off the ground and reduce fire scars but they will generally still kill any nearby vegetation
• some of these are designed to have high air flows and thus “smokeless” but they will consume fire wood faster

• these are generally small flat fold metal stoves designed for twigs, etc to boil water

• these are much less likely to cause nearby damage from embers
• function much better in windy conditions - open camp fires MUST NOT be lit in windy conditions
• use much less wood
• much easier to light in the rain
• can be used to create a hot tent with ventilation and fire risk precautions in place (eg. Flashing Kit, Triple Wall Pipes, Fireproof Matting) - if the tent is not heat tolerant (eg. lightweight nylon tents) you will need to place the stove at a distance
• NOT suited to larger groups
• see wood stoves for camping

• 60-80% of the heat from a fire escapes upwards due to convection and this component is hard to utilise unless you have a wood stove inside a tent or similar shelter (although the need for ventilation to reduce risks of carbon monoxide will also mean much of this is lost even inside a shelter)
• hence the most useful heat for most campers with an external fire is radiant heat which, like a torch light:
  • travels in straight lines from the heat source
    • unfortunately much of this at near ground level can be blocked by fire pit enclosures which will stop the radiant heat rays reaching your bed or if you are sitting on a low chair
  • like normal light, its intensity drops off by the square of the distance from the source so that the heat at 2m will be 1/4 that at 1m and at 3m it will be 1/9th that at 1m
    • hence for a larger group around the fire you will need a larger fire to give off enough heat for a 2-3m distance.

• the major problem when you are lying down is that only one side of you will receive the radiant heat from a fire, and even this may be blocked by the edge of an elevated stretcher bed, so we need to find a way to direct some radiant heat rays down on top of you as well
• create one or two parabolic silver reflective surfaces:
  • one behind you and reaching above you so that it reflects any radiant heat down on top of you
    • this could be by lining the inside rear and ceiling of a dome tent, or you could create your own structure to achieve this
  • optionally, a second one placed on the far side of the fire so that it reflects the radiant heat which is going away from you back towards you while the parabolic shape helps to concentrate it and make up for the extra distance the heat must travel
  • this could be made from Mylar type space blankets
• optionally create a greenhouse effect
  • by enclosing you shelter in a transparent sheet material such as clear TPU which allows the radiant heat rays to pass through but then keeps the warmth next to you, you can further optimise your warmth
  • be careful though that this material is adequately secured so that it cannot get too close to the heat source that it will melt or catch on fire
  • this may create internal condensation so you may need a towel
• you still need insulation from the ground so you don't lose body heat to the ground such as:
  • high R rated self-inflating air mattress
• NB. clothing BLOCKS radiant heat
  • the less clothing you have on, the warmer your skin will get from radiant heat - bare skin works the best if you are close enough to the radiant heat and your skin is facing the heat direction (hence the need for the parabolic reflector above and behind you if you are lying down
  • clothing is an insulator and impairs the ability of the radiant heat to warm you up - and if you do get warm, you are likely to get sweaty which will eventually make you cold when the fire dies down

• potatoes or sweet corn
  • wrap potatoes or sweet corn in aluminum foil and place on hot coals, rotate frequently, and wait til cooked
    • perhaps 10-20 minutes for sweet corn
    • ~30 minutes or so for potatoes depending upon size
• marshmallows - but don't let them catch fire!
• bananas and chocolate or marshmallows
  • slit a banana longways through the concave inner curve through the peel and through the banana but stopping before you get to the peel on the other side
  • open the banana slit and place chocolates or marshmallows
  • close as best you can and wrap in aluminium foil
  • place in the edge of the fire or on coals and wait about 15-20minutes then open and eat with a spoon