How is radiation bad?

Answer 1

That depends on type of radiation and its energy:

• Alpha (nuclear) harmless unless inhaled or ingested as one sheet of paper or your skin totally shields it. If inhaled or ingested can cause cancer decades later.
• Beta (nuclear) causes burns, requires several inches of metal to shield.
• Gamma (nuclear, very high energy electromagnetic) very dangerous and hard to shield. Requires many tens of feet of dense metal (e.g. lead) to shield.
• Radio (low energy electromagnetic) considered harmless.
• Microwave (medium energy electromagnetic) cooks exposed flesh, but fully shielded by properly operating microwave cooker.
• IR (medium energy electromagnetic) this is heat, enough can cook or burn. Can be shielded with many materials.
• Light (medium energy electromagnetic) considered harmless, you could not see without it.
• UV (high energy electromagnetic) causes suntan and sunburn, can be shielded with sunscreen lotions.
• X-Ray (very high energy electromagnetic) dangerous but used to photograph broken bones, etc. Can be shielded with thin sheets of lead or other dense metal.

Answer 2

In general one could say that the the situation is not all bad, there is radiation going through your skull right now. When levels get to a thousand times background levels that's when you need to worry.

The are many types of radiation, and they fall into either of three categories: electromagnetic waves, subatomic particles, and cosmic radiation. Electromagnetic waves incorporate a huge spectrum some of which can be quite hazardous: x rays and gamma rays. X rays are used, in low dosage, in medical testing. Gamma rays should always be considered highly dangerous. Ultraviolet radiation causes sunburn which can lead to skin cancer. No other electromagnetic radiation has been shown to be hazardous in the amounts we are ever subjected to. Subatomic particles that we might be exposed to are mostly electrons, protons, and helium nuclei. They can be quite hazardous to skin and any other organs that they get close to, but are easily shielded. Cosmic radiation consists of a large family of particles that come to earth from stars, mostly the sun. Similar radiation comes from nuclear explosions (bombs, not nuclear reactors). Fortunately, no one has used a nuclear bomb since World War II and cosmic radiation is almost entirely stopped by the atmosphere before it reaches sea level. In an airplane at 30,000 feet or on top of a mountain there is some exposure, but it does not seem to have harmful effects.

Don't worry be happy now!!