Simon Lewis Posted November 4, 2005 Share Posted November 4, 2005 Hi y'all, There's quite a few on the list who teach in FE and HE. Could you state your present method of managing student's noise exposure in taught activities (rehearsals, recording studios, workstations, live productions etc.)? Do you have any specific measures in place to deal with the changes coming in next April? I'm starting to plan for the re-assessment our activities, and would be grateful for any examples of best practice. many thanks, Simon Lewis Link to comment Share on other sites More sharing options...
paulears Posted November 4, 2005 Share Posted November 4, 2005 I would bet that very few FE or HE centres are even aware of the changes. Pretty well my experience is that unless there is an efficient H&S person (and most don't have one) they will be totally unaware. I'm planning to incorporate spl issues in some of the new BTEC units that are going to be updated next year. Most colleges won't be aware of this area at all. If, and it's a big if, the centres have staff engaged in the professional world, they may be aware of it. Plenty, don't. It is a bit unreasonable to expect the drama or music teacher to be up to speed. If it isn't in the spec - it doesn't exist. Technical staff may know about it, but as the work may well just be added to their duties, many will have selective deafness. If you think otherwise, think about copyright issues - what colleges do you know that do PRS returns. Based on the fact the hairdressing section have a PRS sticker, nobody else bothers. All the music played by the bands, all the copyright videos that specifically ban educational use - totally ignored, just as the new noise at work regs will be. So speak the cynic! Link to comment Share on other sites More sharing options...
Simon Lewis Posted November 5, 2005 Author Share Posted November 5, 2005 Paul, I'd certainly expect a lethargic response from the entertainment world, but had thought that education was more switched on? At my uni, the original NaWR were properly implemented in 1990, and as I was working as an environmental consultant at the time, spent many a happy hour doing noise assessments. Now that the new regs are 6 months away, it seemed pertinent to check our position. I rememmber a Scottish conributor to the Theatre Sound group stating they had to use level limited headphones at their FE college, and had guessed that restrictions might be higher in that end of the sector due to younger people being involved? I suspect that this may reach the public consciousness, due to the usual scare stories of orchestras having to quieten down - just as a recent radio 2 programme ran a whole phone in on work at height regs ;-) Simon Link to comment Share on other sites More sharing options...
J Pearce Posted November 5, 2005 Share Posted November 5, 2005 The sixth form I attend has recently purchased a dB meter, which is now to be used at all concerts. The plan is: If the level exceeds a certain predetermined level (can't remember it, sorry) anywhere where a person could be then the musicians or sound technician is informed and the level is reduced ASAP. The first concert this was put into action was at a mid-scale rock concert one lunchbreak. The plan worked well with readings taken at soundcheck and I was then informed where I was in regard to the predetermined level. At no point in the gig did the levels go over and I had regular feedback from the staff member responsible for taking the readings. Steps are being taken to introduce something similar for rehearsals. Link to comment Share on other sites More sharing options...
paulears Posted November 5, 2005 Share Posted November 5, 2005 At no point in the gig did the levels go over and I had regular feedback from the staff member responsible for taking the readings.You've highlighted the problem. Somebody has to instigate the system. I'd bet in most places, this is because somebody who really understands what is going on mentions it at a meeting, explains it to the bemused faces present, and then adds the job to their own job description. At many places, technical support is poor or non-existant. In these centres, professional practice and legal duties don't really exist. Consider the changes in licensing about to happen. Many venues have now applied and received their new licences, some took advantage of the dropping of the daft two performer 'rule'. How many have considered the volume implications? The ones I've spoken to have no idea at all about how to calculate cumulative exposure and even if they bought a meter, what skills do they have to make sense of what it tells them. I'd love to be the inspector going around in a years time asking to see the records. Again, it will be the big venues, probably those in a chain or big group, that will manage it properly. I smiled at the volume restricted headphone scenario. Most colleges lose headphones by theft, damage, and movement between equipment. Financially a volume limited pair is an expensive item. Many places simply buy dirt cheap cans for students and tell them if they want better quality ones, bring in your own. Control of volume - a bit of a laugh. You can't even buy the limiter and 'glue' it to the output, as they have to be matched to the cans themselves. I'd love to be proven wrong - but if someone comes back to this thread in a years time - bu**er all will have happened. As I've mentioned loads of times before - legislation is for everyone, apart from education (or at least that is what most colleges and schools think!) As a test - go into a performing arts department in FE/HE and ask for their department risk assessments, their cossh records, their PAT records and see what you get? PAT will probably be held by someone else (not sure who), coshh will generate a blank look, and risk assessments if in the filing cabinet will deal carefully with wet floors, heavy lifting (with a really low limit set) and cleaning hazards. If you are very lucky there might, only might, be something on ladders. As a test I just sent a text to a person who's never heard of coshh - despite being a college technician with a lock up storage cabinet with hazzard symbols on it in his office. Link to comment Share on other sites More sharing options...
J Pearce Posted November 5, 2005 Share Posted November 5, 2005 You are right Paul. Ross, our music tech teacher was responsible for the dB meter, and I am pretty sure if he hadn't been in that day (he only works 3 days a week) it wouldn't have been done. As with the headphones I know the college I attend could not afford limiter fitted headphones. The college buy £4 headphones in bulk, and if you want better you get your own. Is volume limited headphone amps a possibility, I know they're not as good as calibrated headphones, but more practical. Link to comment Share on other sites More sharing options...
paulears Posted November 5, 2005 Share Posted November 5, 2005 No, the limiting has to be done between the headphone plug and the headphones. Sensitivity and impedeance vary hugely on different types, so if the amp was limited to be ok for brand X cans, brand Y could be much, much, louder. Link to comment Share on other sites More sharing options...
Jivemaster Posted November 5, 2005 Share Posted November 5, 2005 Theres still much knowledge to be disseminated, and there always will be. I heard recently of a manager buying chemicals on the basis of the length of the manufacturer's COSHH statement, 1 page good therefore buy. 8 page bad - more hazard dont buy.Sadly the two products were the SAME so a manufacturer's inadequate supply of CoSHH data was effectively a positive selling point. Expecting the non-english-speaking events staff at most venues to understand the concept and maths of a noise dose is impossible. Link to comment Share on other sites More sharing options...
J Pearce Posted November 5, 2005 Share Posted November 5, 2005 I realise the impedance/sensitivity issue, but if a college calibrated their headphone amps to be safe when using their headphones, then if someone used their own headphones it would be the same as someone bringing in their own unlimited headphones. All the headphones within one school/college seem to be the same so this could be practical. Link to comment Share on other sites More sharing options...
Andrew C Posted November 10, 2005 Share Posted November 10, 2005 Somebody has to instigate the system. I'd bet in most places, this is because somebody who really understands what is going on mentions it at a meeting, explains it to the bemused faces present, and then adds the job to their own job description. At many places, technical support is poor or non-existant. In these centres, professional practice and legal duties don't really exist. That's me! and for the moment I don't really understand but I've more of an idea than anyone else. Oh, I am the technical support! I've asked over in a sound thread for advice on meters, so I'll ask here for advice on books and/or training... Link to comment Share on other sites More sharing options...
paulears Posted November 10, 2005 Share Posted November 10, 2005 I realise the impedance/sensitivity issue, but if a college calibrated their headphone amps to be safe when using their headphones, then if someone used their own headphones it would be the same as someone bringing in their own unlimited headphones. All the headphones within one school/college seem to be the same so this could be practical. Nope - the practical reality is that when the next order is written out, it will be for the special offer just arrived from people like CPC - now let's say the new batch arrive, who will callibrate them? I don't know anybody who has an artficial head with the capability of testing spl at the ear drum. It is a lot more complicated than it appears. Cost is a factor too - twenty sets of budget headphones will need doing one at a time. This is expensive. The idea of the headphone amp also implies nobody can tuen the wick up, or bypass whatever limiter is in use. The limiter also has an impact on the peoples exam results - if the system hard limits to meet a standard, how can they tell what limiting effect comes from the proper use of equipment and what comes from the uncontrolled result of a brick wall limiter to prevent over exposure. How many kids know more than the technicians - quite a few probably, and you can bet they'll get around whatever you do. How do you monitor exposure to Marshall stacks turned up to 11 on a 1 to 10 scale? In schools and colleges the only person in a position to control this is the teacher, and they have other priorities. If the PC people get to run the system it will be fun. I don't like to say unworkable, but pretty close, I think. Link to comment Share on other sites More sharing options...
Simon Lewis Posted November 10, 2005 Author Share Posted November 10, 2005 I've asked over in a sound thread for advice on meters, so I'll ask here for advice on books and/or training... Books: Managing Noise & Vibration at Work - Tim South 0-7506-6342-1 Training: The Institute of Acoustics run a short course for those who need to carry out workplace noise assessments. It may well be beyond what you need, but it's a good course. The HSE have a number of publications on reducing noise, but most are geared towards industry where noise is the unwanted byproduct. Specific queries:I'm happy to answer specific questions, and I'd guess that Mr Si would be happy to help as well... The Entertainment Industry is being given two years to come up specific guidance on how to meet the new regs... I haven't heard too many suggestions yet ;-) HTH, Simon Link to comment Share on other sites More sharing options...
Simon Lewis Posted November 10, 2005 Author Share Posted November 10, 2005 If the PC people get to run the system it will be fun. I don't like to say unworkable, but pretty close, I think.Paul, That's why I'm trying to find out examples of good practice... I rejected the idea of headphone limiters long ago (despite the Scottish gentleman's comment that the "safety Inspector" would close him down without their use). I don't want to have to monitor every rehearsal, workstation and live gig, but I do want students to gain an appreciation of what is a workable level and what is just silly and irresponsible. Year 2 have just started doing their own audiograms. It's quite a revealing time, as a number will find they have noise induced hearing loss at the tender age of 19 - 20. Many get quite upset, and vow to protect themselves in fuure, but the damage is already done. Should we only ever play at 80dBL(A)eq ? Probably not, but the modern equivalent of sticking your head in a bass bin does seem to be alive and well... Simon Link to comment Share on other sites More sharing options...
paulears Posted November 10, 2005 Share Posted November 10, 2005 When I got involved with Edexcel and we dreamed up the A level music tech spec, the very first year (I think it was 97/97?) I did the audiogram idea by a very crude system. I used a 20-20K slow sweep, reading 0dB on the desk meters. A akg 414 on a stand centre, feeding the meter next to the sweep, and set to also give 0dB mid band. Ignoring the response of the equipment, loudspeakers and mic, I'd start it and get everybody to put their hand in the air, and drop it when they could no longer hear the tone. The first couple of years we had mainly middle class people who played 'real' instruments who used to do A level music. I was always the first to lower my hand. As the people in the class gradually moved accross to 'long guitar strap merchants' - no insult intended, but everyone will know what I mean, it was a shock to see my hand up, and some of theirs down. I did send a couple to the local audiology clinic at the hospital, via their gp and they got the bad news that their hearing was impaired - all with frequency specific losses - not gone, but reduced. What really was sad was that those people learned, and lowered their playing volume - but nobody else ever did. It is actually musically self-defeating anyway, since your ability to discriminate pitch also gets worse as levels go up. recordings they made were always painful to listen to because nobody seemed to notice the guitars weren't in tune with each other! Perhaps a pub type volume limiter with flashing amber and red lights might be best? Link to comment Share on other sites More sharing options...
Simon Lewis Posted November 11, 2005 Author Share Posted November 11, 2005 Perhaps a pub type volume limiter with flashing amber and red lights might be best? That's pretty much what I'm suggesting for our rehearsal rooms... There's a device that increasingly lights up when the preset level is exceeded, and it's possible to log levels over a week or two so that excessive volume can be traced to a particular time. I've also carried out the swept sine test (OK a 1/3rd octave step from NTIs sexy little software Minirator!) and most hands are down by 16kHz, with a few significantly earlier. Whilst we don't want to be mollycoddled, a little gentle warning won't go amiss. Simon Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.