Friday, July 28, 2006

Quiet Bangkok - Noise Level Meters

A comment below requests information on the availability of noise meters. Like mobile telephones there is a wide range available. The following paragraph is buried in one of the archives.

For the serious campaigner against noise, a noise level meter is a necessary weapon! The simplest kind which gives an instantaneous measure of noise level is sufficient for spot measurements. With the evidence of a decibel figure one’s complaint has real relevance. The model I use is a TES-1350A made in Taiwan. I have used it for over two years without problem and its accuracy compares well with far more expensive models. Specifications, prices, and ordering information may be seen on the web-site http://www.tes.com.tw/

Evidence regarding habitual noise levels require an instrument that can give a reading that has been averaged over several hours, say the ten working hours, or a full day. However, we usually want to know where a present noise ranks on the tolerable or intolerable scale of noise such as that illustrated on the noise table below. For this purpose the TES-1350A is adequate.

Monday, July 24, 2006

How to make noise about noise

Following difficulty in submitting complaints about noise to BTS, Quiet Bangkok thinks it opportune to repeat a post which is buried below in the archive.

To complain about noise there are several options. For a one-off all night party or a noisy car left with the engine running etc. your local police station is the best option. If you report that you saw three men murder someone, they will record it but are unlikely to do much. But if you complain of excessive noise at three in the morning a policeman will probably arrive on a motorbike to admonish the cause. If there is a long term source of noise such as a karaoke night club you may get help once, but the problem will recur.

Try the following:
Central police contact number 191. They may be more effective than you in generating action from your local station.
Bangkok Metropolitan Administration 1555
Pollution Control Unit 1650

สถานีตำรวจในท้องที่ 191
ร้องทุกข์เสียงดัง กทม 1555
กรมควบคุมมลพิษ 1650


For more serious letter writing, mail to the Governor of Bangkok:

อภิรักษ์ โกษะโยธิน
ผู้ว่ากรุงเทพมหานคร
173 ถ.ดินสอ
แขวงเสาชิงช้า,เขตพระนคร
กทม 10200

Apirak Kosayothin,
BMA office
173 Din-Sor Road,
Sao Chingchaa,
Pranakorn Area
Bangkok 10200

email: apirak@bma.go.th
and please send a copy to: nathanon@bma.go.th ,high ranking and efficient official in BMA

For loud and clear complaints about noise on the BTS rail system, go for:
See following post

Friday, July 21, 2006

BTS Contact

For loud and clear complaints about noise on the BTS rail system, go for:
Dr. Anat Abhapirama, Adviser to BTS Board of Directors
1000 Pahonyothin Road,
Jatujak Area,
Bangkok 10900
tel: 02 617 7300 ext 1884 ( hot line centre )
fax: 02 617 7133, 02 617 7155
email to BTS : nuduan@bts.co.th

ดร. อาณัติ อาภาภิรมย์

อาคารบีทีเอส 1000 ถนน พหลโยธินลาดยาว จตุจักร

กรุงเทพฯ 10900
โทรศัพท์ : (66) 2617 7300 ext. 1884
โทรสาร : (66) 2617 7133, 2617 7155
อีเมล์ : nuduan@bts.co.th
ศูนย์ฮ้อตไลน์: (66) 2617 6000
ศูนย์บริการนักท่องเที่ยวบีทีเอส : (66) 2617 7340

Thursday, July 20, 2006

ZENN - Zero Emission No Noise

Zenn is an electric car, known in Europe as Microcar. Several tens of thousands of them already run on Europe's roads and there are 800 distributors in 14 countries. The original design is by a Canadian company called Feelgood Cars and they will be marketed in North America from August this year. A link to the company website is given in our links column on the right side of this page.
What a dream if they appeared on the roads of Bangkok:

NO POLLUTION, NO NOISE

Here are the specifications:
Maximum Speed: 45 Km/hr
Distance on a charge: 56 Km
Recharge: 8 to 9 hours: an 80% charge can be achieved in 4 hours
Batteries: six 12V electrolytic batteries, giving 5 HP
There is also a version using Li ion batteries which allows a distance of 100 kms between charges, but charge time is 10 to 12 hours.

Well, yes, the car looks a bit stubby, but think of the parking advantage. Please, readers of Quiet Bangkok, please begin to import, buy, manufacture locally; what a dream city we can have.

Sunday, July 16, 2006

Useful Table - Those Decibels Again

Common Noise Levels and Typical Reactions


Below is a useful comparative table of noise levels. But what does Apparent Loudness mean?

Alright, it is a bit complicated!

Let us start at a noise level of 70 db. We experience this sound because a certain level of noise energy is reaching our ears. Now suppose we double the energy reaching our ears. A noise meter will tell us that the noise level is now 73 db (a rise of 3 db in noise measured on the meter is always due to a doubling of the noise energy level in the air around us, e.g. 43 db has twice the noise energy of 40 db, 63 db has double the noise energy of 6o db and so on) . But the sense of sound in our brain does not react to the noise energy level in the same ratio. A rise from 70 db to 73 db does not feel to us like a doubling of the noise, it sounds like much less. For us to think that the noise has doubled, the noise energy level outside has to increase TEN times (which a noise meter will register as an increase of 10 db)!
So if we start at 40 db and increase the noise to 50 db, the real noise energy outside has increased 10 times, but our ears tell us that it has only increased 2 times i.e. the apparent loudness has doubled.
If we increase further to 60 db, the real noise is now 100 times greater but our ears tell us that it has increased 2 times from 40 to 50 db, and another two times from 50 to 60 db or 2 x 2, or 4 times altogether. Increase the noise once more from 60 to 70 db (the noise outside has now gone up 1000 times more than at 40 db); our ears tell us it has gone up 2 x 2 x 2 or 8 times compared to 40 db.
Finally increase the noise outside another 10 times. A meter will record an increase from 70 to 80 db; the actual noise energy has now increased 10,000 times but our ears tell us it has gone up 2 x 2 x 2 x 2 or 16 times greater than it was at 40 db.
So there you are!


Let me summarise:

40 db Reference level

-----------Real Noise Level ----------APPARENT LOUDNESS

50 db -----increased by 10-------------- increased by 2
60 db -----increased by 100------------ increased by 4
70 db -----increased by 1000 -----------increased by 8
80 db -----increased by 10000 ---------increased by 16
************(compared to the levels at 40 db)**********


Activity

Noise Level [dB(A)]

Apparent Loudness

Typical Physical Response


Rocket launching 180
Danger level

Threshold of pain
Gunshot
Jet engine taking off

140
Danger level

Military jet
Air raid siren
Shotgun
Hydraulic press (3 m away)

130

512 times as loud

Limited ability to hear amplified speech.
Noise may cause pain.

Can damage hearing after 3.75 minutes exposure per day

Car horn
Propeller aircraft
Air-raid siren
120 256 times as loud Can damage hearing after 7.5 minutes exposure per day

Sand-blasting
Squealing pigs
Inboard motorboat
Typical night club
Unsilenced motorcycle (7m away)

110

Over 128 times as loud!!

Maximum vocal effort.

Can damage hearing after 30 minutes exposure per day

Amplified Rock Music 110-130 Over 128 to 512 times as loud!! Can damage hearing after
3.75 - 30 minutes
exposure per day
Helicopter
Motorised/power mower
105
Can damage hearing after 1 hour
exposure per day

Jet takeoff @ 500m
Train horn @ 30m
Diesel truck
Pneumatic drill/jackhammer

100

64 times as loud

Can damage hearing after 2 hours exposure per day

Heavy truck @ 15m
Busy city street
passing motorcycle
Lawn mower
Loud shout
Sreaming child

90

32 times as loud

Very annoying.

Can damage hearing after
8 hours exposure per day

Average factory
Electric shaver
85

Busy traffic intersection
Motorway construction site
Outboard motor
Alarm clock (with bell)
Freight train (15m away)

80

16 times as loud

Annoying .

Motorway traffic @ 15m
Roadside traffic
Train horn @ 500m
Vacuum cleaner
Mixer
electric sewing machine
Noisy restaurant
Conversation in a loud voice

70

8 times as loud

Telephone use difficult.

Washing machine/dishwasher 65

Light car traffic @ 15m
City or commercial areas
Noisy office
Normal conversation
Clothes dryer
Background music

60

4 times as loud

Intrusive.

Quiet office

50

2 times as loud

Speech interference.

Refrigerator 45

Quiet residential area
Kitchen/bathroom
Public library

40

Arbitrary Base
Reference Level

Quiet .

Leaves rustling
Very soft music
Recording studio
Living/dining/bedroom

30

1/2 as loud

Very quiet.

Threshold of sound perception

10

1/8 as loud

Just audible.

Threshold of hearing

0

N/A

Not audible.

Sunday, July 02, 2006

Noiseopolis

The Nation: Sunday 2nd July

'No measures to curb noise from airport'

Nation: Sunday 30th July
A top ear and hearing expert has expressed concerns about noise pollution around the new Suvarnabhumi Airport, saying the government has taken no measures to deal with it.

"The government lacks clear regulations," said Dr Suchitra Prasansuk, director of the Otology Centre at Siriraj Hospital.

Suchitra said the business-first mentality meant more housing estates being built near the new airport despite the hazard of permanent ear damage as a result of long-term exposure to noise pollution with more flights per minute than Don Muang Airport currently handles.

"In Osaka they built an airport far away from the city," she said.

Jet-engine sound often reaches 120 decibels while the normal acceptable level is 70.

Most susceptible are schools in the airport's vicinity. Suchitra said that aside from ear damage, long exposure to loud noise from the airport could lead to children in the area developing aggressive behaviour. She said some 20 per cent of students in urban schools next to major roads developed hearing impairment.

"Many don't have their ears examined, and if they're not functioning well they conclude that that's just the way it is," Suchitra pointed out. "People know nothing and think nothing about it. If you can't hear well for five to seven days [and do not seek treatment] you could ended up developing permanent damage."

Suchitra said one way of tackling the issue was to install noise-measurement boards at the new airport and other major traffic spots to warn people of the dangerous level of noise.

Pravit Rojanaphruk

The Nation