1. A newsletter from sIGICom! No. 1 / 2010
INFRA MeAsuReMeNt NewS
KänSligT bygge measurements for unattended monItorIng
IntellIgent noIse KRäVeR noggRanna mäTningaR
USA-mäSSA ComPlICated sound enVIronment
en frAmgång
SWEDISH RAIL LINE REQUIRES ADVANCED MEASUREMENTS FOR COMFORT LEVELS
noIse measurement sorts out
PoRTugal SPRängeR med PReciSion och SäKeRheT
2. no. 1 2010
Editorial
We are all sensitive to noise!
Vibration levels caused by blasting are relatively high and buildings Another article describes how we can
need to be protected from potential adverse effects. People, how- systematically map vibrations emanat-
ever, have entirely different sensibilities when it comes to noise and ing from rail traffic. Since we measure
vibration and the disturbance they cause. Especially when distur- inside buildings, it is important to be able
bances happen at times of day that are normally a little calmer. to differentiate the relatively small vibra-
The INFRA-system allows cost effective, autonomous, long-term tions caused by the train from the normal
monitoring of noise and vibration to ensure that levels fall within vibration levels of the building itself. This
specified boundaries that often vary throughout the day. When is accomplished in a simple way and is
boundaries are breeched, a recorded signal is received in the of- described in the article.
fice so that the cause can be determined, which is a prerequisite
for taking appropriate measures. In this issue we describe how the
Christer Svensson
INFRA noise monitoring system and long term measurements can CEO, Sigicom AB
determine the reasons for the disturbance. Causes are not always
what we might expect. Existing vibration and noise environments
can also be mapped out with the INFRA-system, which helps in
planning new construction or safeguards for protecting existing
buildings.
Intelligent noise measurements for unattended monitoring
noise can occur at any time or any place - indoors and outdoors.
unattended monitoring allows noise to be easily measured and analyzed.
and if disturbances suddenly exceed stipulated levels corrective measures
can be implemented faster.
The INFRA S50 features a high quality measurement microphone
and electronics for digital signal processing. The meter is a type
Want to knoW more?
1 and can be directly connected via a bus cable to an INFRA field
measurement system. All filtering and signal processing occur
digitally in the sound level meter. When recording begins from an
INFRA Master unit the user chooses the measurement configura-
tion.
Maximum and equivalent sound levels are measured simulta-
neously and measuring intervals can be set anywhere from 5 sec-
onds to 20 minutes. It is also possible to designate a trigger level Please contact roger Lindstrand,
for recording of time courses. The operator can quickly ascertain roger.lindstrand@sigicom.com
the reason for high noise levels by analyzing the time course within
INFRA’s software package.
Several measuring units can be switched on from the same
INFRA Master unit and users can combine vibration sensor
devices with sound level meters. If noise occurs at different
locations, a meter can be mounted near each noise source.
Measurements are carried out simultaneously in the places where
disturbances are noted. All measurements are time synchronized
via Internet time servers so that noise disturbances can be com- INFRA S50 for
pared directly with the noise at the respective source. unattended monitoring
No. 1 / 2010 PUBLISHED BY SIgIcom AB
3. Advanced comfort level measurement
along the Mälarbanan rail line
The mälarbanan rail line from Stockholm will be extended by several tracks with some
of the construction conducted in very densely populated areas. This means more trains
operating at higher speeds, and thus more noise. banverket (Swedish Rail administration)
is facing some decisions regarding noise and vibration dampening measures. The high
costs involved require that decisions are based on careful measurements and forecasts.
Andreas Wennblom,
acoustic and vibration
consultant with WSP
Acoustics
A section of the actual track line surrounded by business and residential property. V10 V12
W SP Acoustics received the contract
to measure daily vibrations along
three kilometers of track in the Stockholm
between 65,000-70,000 passes within the
actual project testing area.
A vertical geophone is placed on a stake
counter measure suggestions and therefore
Banverket’s future costs,” says Andreas.
“These geophones can measure fre-
suburb of Järfälla and to forecast the effect in the ground near the track and functions quencies down to 1Hz. The system is also
of increased rail traffic and suggest counter- as a triggering mechanism. When a train durable, weather resistant and easy to work
active measures. At least 100 properties are passes it triggers the other two geophones with, and that also makes it the most price
directly influenced and more than 100 more – one on the ground wall (V10) and one worthy. After a one day training session
indirectly. inside the dwelling or office (V12). Data in Stockholm, our personnel knew how
The area includes villas, apartment recording time is normally 15 seconds. The to operate the equipment on their own. I,
complexes, and offices located on vibra- master unit registers the data and sends myself work out of Jönköping , many miles
tion sensitive land in the form of sea floor it on via GSM to Sigicom’s measurement away from the site. All parameter configura-
with streaks of clay. The maximum level is data base. From there, Andreas can access tion and synchronization were made in one
1mm/s RMS indoors, and anything over the information at WSP for analysis and day at the office before the project began,”
that requires action. Andreas Wennblom forecasting. By triggering the geophones, Andreas points out.
has a hand in measurements and analysis. vibration sources other than passing trains
At the time of interview there were 25 prop- are eliminated from the measurements. Customer facts
erties nearest the tracks that were being
WSP Group is a British-Swedish business group
monitored for vibration with a comfort filter. Why the INFRA measuring system?
with wide operations in the area of management,
An INFRA measuring system for a “It is the only system really suited for this public buildings, environment, project planning and
property in this project consists most often project. I know of nothing comparable, more. The group employs over 10,000 worldwide,
of two vertical geophones (V10), a tri-axial at least not in Sweden and not for indoor 2,000 of which are in Sweden. The Swedish
(V12) and a master unit. Four such systems use. Not only do I get the top count of operation stems from a merger between WSP and
each vibration wave, but I also get the Jacobson & Widmark in 2001. WSP Acoustics,
are used in parallel and are usually moved
where Andreas Wennblom is employed, has
once a week to different properties. In gen- time, acceleration and frequency. Low
currently 50 employees and is considered one of
eral, a train passes by every three minutes frequency vibrations can be a problem
the country’s leaders in the branch.
during the day. In total, Andreas estimates as well. Frequency issues influence the
No. 1 / 2010 PUBLISHED BY SIgIcom AB
4. Whose noise is it anyway?
RECEIVER:
– ÅF separates the noise sources in a complicated
sound environment
The sound environment surrounding scrap metal recycling company Ragn- SENDER/RETURN ADDRESS: Sigicom AB
Alfred Nobels Allé 214, SE-146 48 Tullinge, Sweden
Sell’s facility in the city of Västerås is a complicated one. The municipality
requires regular noise control, but between the facility and the nearest
residential area there is both a rail line and an automobile road. There are
other sources of noise in the area as well.
“We began with near field measurements of noise sources
within Ragn-Sell’s facility,” says Paul Appelqvist of ÅF-
Ingemansson, the company in charge of the assignment.
“From this measurement data we put together a noise map,
which allowed us to make changes in the operation, and thus Paul Appelqvist,
ÅF-Ingemansson.
approved noise levels in the residential area were reached.”
A control plan with measurements conducted for one week
every 6 months has now been in place for 5-6 years. With the
help of the INFRA equipment, S50, the company has been
able to separate the various sources of noise and report them
in the measurement data so that guidelines set forth by the
municipality are not exceeded.
“At first we had another contractor supplying measurement
equipment, but there were breakdowns and malfunctions, and
the equipment had no means of remote control. The INFRA
equipment is reliable and weather proof, even the master unit is
impervious to bad weather. And in addition, there is no power
source required. Battery life is fine for our measurement periods, Ragn-Sells recycling facility for scrap metal in Västerås. S50
and the equipment is easy to operate remotely,” says Paul.
Facts on ÅF-Ingemansson and Ragn-Sells
Remote controlled trigger levels
In addition to isolating noise sources outside Ragn-Sells, it is The ÅF Group is one of Sweden’s largest technical consulting firms with
important to set the correct trigger levels and adjust them fur- approximately 4,500 employees located in 70 offices in 19 countries.
Ingemansson was acquired in 2006 and is currently a part of ÅF’s Infrastructure
ther when changes occur in the sound environment. division. The company has more than 50 years experience dealing with noise
“At the chosen trigger level we also record a sound se- and vibration issues. Currently there are 80 employees working out of 10 offices
quence so that we can later clarify the sound source. We have in Sweden, Denmark and France.
learned from the complaints of the local residents that the dis- Ragn-Sells employs 2,300 and is one of Sweden’s largest environmental and
recycling companies and the market leader in a number of segments. The
turbing noise comes from other sources, and not Ragn-Sells”,
company collects and recycles scrap and waste products from residential and
says Paul. industrial sources at a large number of recycling plants. Ragn-Sells deals with
It is a big advantage that parameters can be remotely all types of refuse with the exception of nuclear waste. They also provide con-
sultant services for environmental studies and life cycle analyses, among other
configured. For example, trigger levels can be adjusted from
things.
ÅF Ingemansson’s office in Solna, even during an ongoing
measurement period.
“We are now looking forward to INFRA Net, which will
upcoming events with sigicom
simplify things even more. The client will be able to follow the
measurement process live on the Internet as it occurs,” says a XXX xxx
happy Paul Appelqvist. www.xx.xx
ADDRESS Alfred Nobels Allé 214 TELEPHONE +46 8 44 99 750 E-MAIL info@sigicom.com
SE-146 48 Tullinge, Sweden FAX +46 8 44 99 769 INTERNET www.sigicom.com