ParkerJones Acoustics - Noise and Vibration Explained

B gives me another excellent topic which I’m very familiar with, which is…  Building Acoustics . Now I appreciate that it looks like every topic in this A to Z will be a different word simply followed by the word ‘acoustics’, but I promise… it’s not going down that road, there will be some variety! Anyway… a common misconception (along with eggboxes on walls) is that Building Acoustics means designing concert halls and recording studios, types of space which have a strong connotation with good acoustics and quality of sound. However, it’s also an important aspect for any building which contains ‘noise-sensitive’ spaces, which is most buildings, i.e. our homes, places of work or education, healthcare facilities and places of recreation and leisure. It can have a huge impact on our living comfort, health and wellbeing, productivity and communication. So, what is Building Acoustics?   Well, the clue’s in the name, so you’ve probably already guessed that it’s to do with the a...

Fortunately, the name of the topic I’m covering in this A to Z series of short articles has given me a pretty convenient place to start with for the letter A, acoustics. Acoustics is an area of physics which deals with waves in gases, liquids and solids. The most common topics within this are sound, noise (an unwanted sound), and to a lesser extent vibration. But as the diagram below shows, it’s a very broad area. R. Bruce Lindsey in J. Acoust. Soc. Am. V. 36, p. 2242 (1964) Firstly, I should explain, my profession is as an ‘Acoustic Consultant’. In short, I deal with acoustics, noise and vibration that would occur in your everyday life. Whether it’s your home, place of learning or place of work, or the method of transport you use to get there, at some point, an acoustic consultant like myself would (hopefully!) have had something to do with it. If I were to categorise myself based on the ‘Lindsay’s Wheel of Acoustics’, my work would be predominantly in the Engineering q...

Articles Making sense of Noise Surveys Share Share on facebook Facebook Share on twitter Twitter Share on linkedin LinkedIn Author Chris Parker-Jones December 18, 2019 The aim of our articles are to break down acoustic terms and concepts as simply as possible, without going too far into the mathematics and every nitty gritty technicality, that acousticians usually love to get stuck into. So please, if you’re an architect, contractor, developer, planner… or really anyone who occasionally needs to dabble in acoustic design and assessments… then read on… Got a question? Is there an acoustic, noise, or vibration related topic or problem that you would like explained?  Send us an email and we’ll write an article about it. chris@ parkerjonesacoustics.com Why do I need a noise survey and what is all this jargon in my report? As an acoustic consultant I s...

As an acoustic consultant I see hundreds of noise survey reports every year.  Noise Surveys  are probably the most common element of work for an acoustician, so what are they, why do we need it and how do we conduct them? Why do we carry out  noise surveys ? For this article, I’m going to focus on noise surveys for new or refurbished buildings. In this area, surveys are conducted for two main reasons. 1.  Noise Ingress  — In any noise sensitive building (which is most buildings), we have indoor ambient noise level targets to meet within our development. Noise will transmit through the ventilation openings, glazing, doors, walls and roofs in our building façade, therefore we need to know how noisy it is outside and hence the degree of sound insulation we need. This informs the choice of our constructions, particularly important in determining ventilation openings and glazing, typical acoustic weak points.  You may hear an acoustician refer to this a...

Sound Pressure and Sound Power - what's the difference? The difference between sound pressure and sound power can be tricky to get your head around. For predicting noise levels from noise polluting sources like plant, it is very important.  As a consultant, I’m often verbally quoted noise levels by clients, i.e. ‘this unit has a level of 60 dB’. Unfortunately, based on that alone, I can’t do a great deal, without making a lot of assumptions. If you tell me it’s 140 dB I know it’s going to be very loud and problematic! But at 60 dB, depending on the situation, it’s difficult to assess the risk. What is a sound pressure level (SPL)? A sound pressure is the pressure deviation from atmospheric pressure caused by a sound wave, in pascals. The sound pressure  level  (SPL) is a logarithmic measure of the ratio of a sound pressure over a reference sound pressure (corresponding to the hearing threshold of a young, healthy ear), quoted as a ...