It’s that of the year again. Summer is on the way and veld is dry. People are getting out more and go on walks and braais. Wind are in the order of the day and so are the worst nightmare of all for the fire fighter community. Veld fires!!!
All veld and forest fires are dealt with under the National Veld and Forest Fires Act (No. 101 of 1998). This law defines a veld fire as a “veld, forest or mountain fire, where veld means the open countryside beyond the urban limit or homestead boundary”. Veld fires are therefore any fire which occurs outside the boundaries of urban build areas and pose the potential of running out of control.
About 90% of veld fires are started by humans; the other 10% are started by natural occurrences such as lightning.
Three components are necessary to start a veld fire: oxygen, fuel and heat.
At least 16 percent oxygen must be in the air for a fire to start (our atmosphere contains 21%.)
Fuel is any living or dead material that will burn. Fuels such as dead plants, dry leaves, pine needles and grass burn more readily than moist green plants because the dead material contains less moisture.
Heat is usually supplied by a lightning strike to a tree or dry grass. People normally start veld fires through carelessly (not properly disposing of cigarette butts) or malicious (intentionally starting a fire) behavior.
How do I know that a veld fire might occur?
It is normally your dry season.
You experience very hot conditions.
There are a lot of potential fuel (e.g. dry leaves, wood, dead plants and grass). You can clearly see long dry grass and plants. o There are moderate to strong winds present.
Why are veld fires important?
Environmentally veld fires can be important to local ecosystems. e.g. smoke and heat are sometimes needed for seeds to germinate.
Veld fires can lead to regeneration of local plant life.
Veld fires can have an economic and emotional effect on people and property directly affected.
Having a better understanding of veld fire causes can help you better prepare and perhaps minimise or prevent veld fire damage.
Did you know?
Veld fires are actually naturally stored solar energy that is out of control? That’s because trees convert all that sunlight into oils that get stored in leaves that end up burning like petrol.
The South African Department of Water Affairs and Forestry (DWAF) developed a Fire Danger Rating which aims to increase the capacity of the general public and Fire Protection Associations to manage veld and forest fires by being aware of the likelihood of fires occurring in a given area at a given time.
Fire Danger Rating
The national system is designed to apply in 42 distinct regions (see map above) each with different fire conditions. Within each region data relating to flammable fuel structure and condition (fuel models) must be specified, together with daily forecast weather data, for inputting to the fire danger model. This model is used to calculate daily forecast Fire Danger Index values. The forecast indices of fire danger are then entered into a Fire Danger Rating Table. The table classifies fire danger rating five categories:
I. When the danger rating is insignificant (blue), the fire danger is so low that no precaution is needed.
2. When the rating is low (green), fires including prescribed burns may be allowed in the open air on the condition that persons making fires take reasonable precautions against fires spreading.
3. When the rating is moderate (yellow), the fire danger is such that no fires may be allowed in the open air except those that are authorised by the Chief Fire Officer of the local fire service and those in designated fireplaces; authorised fires may include prescribed burns.
4. When the rating is high (orange), the fire danger is such that no fires may be allowed under any circumstances in the open air.
4. When the rating is extreme (red), the fire danger is such that no fires may be allowed under any circumstances in the open air, and special emergency fire preparedness measures must be invoked.
Fire danger ratings are communicated to Fire Protection Associations and Chief Fire Officers.
The main contributor to veld fires is human negligence!
Warnings of possible veld fires are normally communicated by your local weather office or disaster risk management centre. If you think a veld fire might occur in your area be sure to regularly listen to the radio and/or watch TV. Also be aware of local disaster risk management officials making neighbourhood calls through loud speakers. A warning is only as good as your reaction to it!