My 26-year old son decided to have a cup of coffee. He took a cup of water and put it in the microwave to heat it up (something that he had done numerous times before). I am not sure how long he set the timer for, but he told me he wanted to bring the water to a boil. When the timer shut the oven off, he removed the cup from the oven.
As he looked into the cup, he noted that the water was not boiling, but instantly the water in the cup "blew up" into his face. The cup remained intact until he threw it out of his hand but all the water had flown out into his face due to the build up of energy. His whole face is blistered and he has 1st and 2nd degree burns to his face which may leave scarring.
He also may have lost partial sight in his left eye. While at the hospital, the doctor who was attending to him stated that this is fairly common occurrence and water (alone) should never be heated in a microwave oven. If water is heated in this manner, something should be placed in the cup to diffuse the energy such as a wooden stir stick, tea bag, etc. It is however a much safer choice to boil the water in a tea kettle.
Please pass this information on to friends and family.
General Electric's response:
Thanks for contacting us, Mr. Williams. I will be happy to assist you. The e-mail that you received is correct. Microwaved water and other liquids do not always bubble when they reach the boiling point. They can actually get superheated and not bubble at all. The superheated liquid will bubble up out of the cup when it is moved or when something like a spoon or tea bag is put into it.
To prevent this from happening and causing injury, do not heat any liquid for more than two minutes per cup. After heating, let the cup stand in the microwave for thirty seconds before moving it or adding anything into it.
I hope this helps.
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Here is what our local science teacher had to say on the matter:
"Thanks for the microwave warning. I have seen this happen before. It is caused by a phenomenon known as super heating. It can occur anytime water is heated and will particularly occur if the vessel that the water is heated in is new, or when heating a small amount of water (less than half a cup).
What happens is that the water heats faster than the vapor bubbles can form.
If the cup is very new then it is unlikely to have small surface scratches inside it that provide a place for the bubbles to form. As the bubbles cannot form and release some of the heat that has built up, the liquid does not boil, and the liquid continues to heat up well past its boiling point. What then usually happens is that the liquid is bumped or jarred, which is just enough of a shock to cause the bubbles to rapidly form and expel the hot liquid. The rapid formation of bubbles is also why a carbonated beverage spews when opened after having been shaken."
If you pass this on ... you could very well save someone from a lot of pain and suffering
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ذات يوم قرّر ابني (26 عاماً) ان يعمل كوب من القهوة. ملأ الكوب يالماء ووضعه داخل المايكروويف لتسخينه، كما اعتاد ان يفعل في السّابق. انا لست مُتأكّدا كم هو طول الوقت الذي وضعه في الفرن، ولكنه اخبرني انّه اراد ان يُصبح الماء مغليّاً. عندما توقف المايكروويف حسب الوقت المطلوب، اخرج ابني الكوب من الفرن.
نظر ابني الى الكوب ليتاكد من علامات غليان الماء ولكنّه لاحظ ان لماء لم يكن يغلي! وفي هذه الأثناء فجأة انفجر الماء المغلي بدرجة شديدة في وجه ابني وبصعوبة تخلّص من الكوب الذي التصق بيده. غطى الماء المغلي اجزاء كثيرة من وجهه واصيب بحروق من الدرجة الأولى والثّانية وهي حروق قد تبقي آثار دائمة مستقبلا. بالإضافة لذلك قد يكون اصيب بفقدان جزئي بالبصر في عينه اليُسرى.
بينما كان ابني في المستشفى ذكر الطبيب المعالج ان هذه الحالة تحدث بشكل مستمر بين النّاس، وأن الماء لوحده لا ينبغي ان يوضع في المايكرويف لتسخينه. واوضح انّه اذا اضطر احد لوضع الماء في المايكروويف، يجب وضع شيء آخر في الكوب لإمتصاص الطاقة مثل ملعقة تحريك خشبيّة او كيس من اكياس الشاي الصغيرة، وغيرها. ودون شك ان تسخين الماء بالطريقة المعروفة بالإبريق على الأفران العاديّة هو آمن بكثير.
توضيح شركة جنرال الكتريك:
السيد وليام،
شكرا على الإتصال بنا. الإيميل الذي استلمته صحيح. الماء والسّوائل الأخرى لا تُظهر فقاعات او علامات الغليان عند تسخينها عن طريق المايكرويف. بل انه قد يصل غليان هذه السوائل الى درجة عاليه جدا من الغليان ومع ذلك لا يُظهِر ذلك اي فقاعات غليان!. وهذه السوائل المغلية بشدة ستُظهر فقاعاتها بشدّة (خارج الكوب) عندما يتم تحريكها او وضع اشياء مثل ملعقة او كيس شاي داخله (بعد الغليان).
لمنع مثل هذا من الحدوث مما قد يسبب اصابات، لا تُسخّن اي سائل لأكثر من دقيقتين للكوب الواحد. وبعد التسخين، اترك الكوب داخل المايكروويف لمدة لا تقل عن 30 ثانية قبل تحريكه او اضافة اي شيء له.
نأمل ان يكون في هذا التّوضيح اجابة على تساؤلك.
العضو الأكثر نشاطاً هذا اليوم 
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