 The HB project and the HB channel are supported by Hi-Fi Klubben. That sound kills good music. Sounds nasty, doesn't it? Well, I'll explain how to avoid this. As we have seen in part 1, these hearing damages are caused by frequent and long exposure to high sound pressure levels. We have also seen that it's just the level over time, not the kind of noise. Audio music is just as dangerous as a pole driver if the average sound pressure level and exposure time are equal. So all three forms of hearing damage can be the result of frequent over exposure to high sound pressure levels. House parties at the beginning of this millennium often expose their visitors to 135 dB sound pressure level A-weighted or higher. That is equal to the sound of a jet aircraft at 50 meters away. One of my editors at that time measured an LEQ of 130 dB. The LEQ is a measure for exposure to sound pressure level over time, meaning that the person in that room was exposed to an SPL equal to that of a continuous SPL of 130 dB. In the US, the Occupational Safety and Health Administration OSHA has set a legal limit of 90 dB SPL A-weighted for an 8-hour working day and 5 working days a week as the maximum for working conditions without the use of hearing protection. Every 5 dB higher level reduces the permitted working time with 50%. OSHA recommends a level below 85 dB. Health and safety regulations in Europe specify 80 dB SPL A-weighted over 8 hours and 5 working days a week as the maximum for working conditions without the use of hearing protection. Every 3 dB louder halves the allowed working hours a day. So at 83 dB you are allowed to work 4 hours and when we calculate further you see that at 95 dBs you are only allowed to work 15 minutes a day. At 131 dBs it's down to a quarter of a second. No need to say you wouldn't want to be there without severe hearing protection if you wanted to be there at all. By the way, if you think European legislation is too strict, medical specialists in this field recently advised 75 dB SPL A-weighted instead of 80 dB to reverse the ever-increasing hearing damage figures. Luckily levels at live events went down due to self-regulation of the market but still even at 100 to 110 dBs, which seems to be the current agreed on levels, you would only like to be there between 30 seconds or 4 minutes to stay safe. Now you don't visit a live concert 5 days in a row but musicians and sound engineers, light engineers and other stuff, think of bar personnel, security and so on, might at least do a few days a week and they are certainly at big risk. You only get hearing damage after a longer period but once you have it, it's irreversible. It starts with a beep in your head when you leave the venue and that stays with you for a day or so. That's the warning the hair cells in the organ of Corti are slightly damaged due to brute force, like corn stalks that are blown to the ground by a storm. And if the damage is not too big, the hair cells will recover given time like the corn will recover when the damage is not too big. But if both the hair cells and the corn stalks are hit by another brute force attack before they have fully recovered, they might not be able to recover again. If you want to see how the ears work, follow the link in the top right corner for a fine video on this subject. The complicating factor is that a normal first world person works 8 hours a day and sleeps 7 hours a night, leaving 9 hours a day to the person to ruin his hearing by himself. I have mentioned motorcycle driving as a risk but even more dangerous is the portable music player, not because it is louder than the wind during motorcycling but because it is easy, especially for youngsters, to listen to a portable music player for hours. Especially now that every smartphone has a music player and every youngster has a smartphone. These devices are capable of producing over a 100 dB SPL in the ear canal, a level that can become dangerous after playing only 4 minutes every working day. There is a strong parallel between hearing damage and obese. They both are first world problems and they both trick you into consuming more than your body can take. The food industry knows exactly how to feed the chemical computer called your brain with signals to keep you eating. Fat, sugar and salt are used to keep you and me hooked to unhealthy food. The music industry does about the same. Heavy bass and highly compressed sounds at high levels make your chemical computer produce excitement and feel good juices. Like with food, once hooked you start with medium, go to super-sized and end up XXL. Combine food and sound and you'll end up being a sad couch potato totally hooked on the matrix. Fighting your way back to a normal life is tough. I know I've been there, food wise. I still am, more or less. But where you normally can regain a healthier weight, there is no way to reverse your hearing damage, instead of getting satisfaction out of a lot, learn again to enjoy fine taste, details, fresh foods and so on. Even a self-made pizza is a lot healthier and tastier than a prefab one. With sound, don't go for the prefab music that first was compressed the hell out and further improved by packing it into MP3. And don't go for the digitally remastered re-release for they normally are bad sounding due to the adding of the audio equivalent of sugar and fat. If you manage to ban highly compressed music out of your life, you still run the risk of getting overexposed to loud sounds. Your body tells you that it was too loud too long by the ringing in your ears when you leave the venue. It's like muscle pain, the signal indicating overload. But if you haven't ignored this signal often, you might not even notice it anymore. Luckily there are smartphones and numerous apps that measure sound pressure level using the smartphone's microphone. There is no absolute value I can give you where you should get the hell out of there, it all depends on how frequent you visit loud venues and how well your ears recover from overload. If you go clubbing once every two weeks in a club that does 100 dBs SPLA weighted, you might be ok, although if your ears do not recover well, even that might be too much. When in doubt, use hearing protection. Even the simple yellow plugs work, although they are somewhat inconvenient. Today there are earplugs that filter the incoming sound so that loud music is stopped while soft sound is passed on to the ear. This way you can still have some conversation in between the music. I used to use simple ones but I now use dubs by Doppler Labs. Depending on what and how you measure, they dampen between 10 and 15 dBs which offers you a 3.5 times longer stay. All earplugs should be inserted like this unless indicated differently by the manufacturer. Grab your right ear by reaching over your head with your left hand. Pull the outer ear slightly upwards while inserting the earplug gently. For the left ear you grab the outer ear with your right hand. It still is a bit weird that the club buys equipment that is able to play that loud, that the DJ endangers his own ears by playing that loud and that the visitor has to wear inconvenient earplugs not to get hearing damage. When the first part of this video went online, the biggest newspaper of my country, The Telegraph, published a poll amongst their readers about the audio level in clubs and pubs. 94% would like to have it somewhat less loud. Only young people would like to keep the level up and find it their right to choose for high loudness levels. I leave you with another useful tip. When in loud surroundings, rather drink beer than indian tonic. The quinine in indian tonic increases the risk on tinnitus. I just drink water, although even drinking too much water is unhealthy. So all reasons to subscribe to this channel and follow me at Facebook, Google+, or Twitter. You can also post questions there but again, view my questions video first. You'll find all information in the show notes below this video on YouTube. If you liked this video, please give it a thumbs up and tell your friends on the web about it. I am Hans Beekhuyzen, thank you for watching and see you the next time or on theHBproject.com. And whatever you do, enjoy the music.