HEALTH & SAFETY V enus, Earth and Mars form part of a Goldilocks zone, a distinguishing phenomenon based on location. Not too close to the Sun and therefore not too hot, and neither too far where freezing temperatures will stop life from forming. Venus has an atmosphere that consists mostly of CO 2 , while Mars unfortunately lacks the CO 2 concentration needed to trap the Sun’s heat. Earth has just the right amount of CO 2 , although these levels are rising due to carbon emissions. FIRE SUPPRESSION SYSTEMS AND CLIMATE CHANGE Fire suppression systems whether chemical or inert have a negligible effect on climate change. For example, fluorinated fire suppression gases such as HFC227 have a global warming potential of 3,500 times that of a CO 2 system. Since the market size of gases used in fire suppression applications make up less than 0.02% of all global warming gases, and considering that less than 1% is discharged, the impact is quite small. Refer to Figure 1. EXPOSURE AND REACTION TO HF Chemical gasses do not affect oxygen concentrations and absorb the heat element of fire. However by doing so the carbon molecule in the chemical bond breaks down and the fluorine component reacts with Hydrogen produced in the combustion process causing Hydrogen Fluoride (HF) and other 70 noxious elements. The HF molecule is incomplete and will react like an acid, whereby breathing in HF will burn the lungs, nose and eyes. The larger the fire the higher concentration of HF, therefore it is extremely important to extinguish fires in the early stages of combustion. LIMIT YOUR EXPOSURE TO HF To work out the levels of HF concentration, count the fluorine (F) molecules: the more Fluorine the more HF, the hotter the fire, the higher the levels will become. For example, HFC227 (FM200) has 7 x Fluorine molecules. (Novec) FK-5-1-12 has 12 x Fluorine molecules, and therefore will produce almost double the HF and COF 2 in a fire. TOO MUCH CO 2 – IS ‘BAD’ In order to extinguish a fire with CO 2 , high concentrations of the gas are used to flood the inflamed area. The system works by combining oxygen reduction and heat absorption from the CO 2 molecule in high concentrations. CO 2 also has the ability to adapt to extended discharges to meet application requirements, such as when suppressing fires in risk areas with un-closable openings or where machine run-down times are present. Be aware that high concentrations of CO 2 are extremely lethal and will overcome any person exposed, even if only for a few seconds. It will also obscure visibility, effectively blinding those present. In the event of being exposed to high levels of CO 2 concentrations, holding your breath will be impossible as any CO 2 adsorbed in your body will enhance your respiratory system by opening up blood vessels to supply more oxygen. It will therefore be impossible to hold your breath! CO 2 is affordable, largely available and effective in extinguishing g fires. g Fig ure Im pact G HG emi ssions M Mton Figure 1: Impact t of o f GHG emissions, , Mtons s of o f CO O 2 equivalents. . The impact t of o f HFC C emissions from m Impac emissi ons, tons C eq uivale nts. T he imp act H HF F e emis sions fro equiv alents missio ns firfire f figh ting r repr esents <0 .03% tf he imp p act al G HG emi ssions ightin eprese nts <0.03 i im mp a m mpact emissi ons. fire e fighting g represents <0.03% % o of the e impact of all l GHG emissions. . ESI AFRICA ISSUE 1 2015