Fire Eater White paper silencer

Silence is golden Maintaining the integrity of HDD’s in a noisy situation

This paper has been created by Fire Eater A/S as an aid to be used by those who have the responsibility for specifying and designing Fire Extinguishing systems incorporating INERGENÂŽ.

The intention of this paper is for it to be used as a guide and is not to be evaluated as exhaustive to all literature available. Due to the varying types of HDD it is impossible to predict their behavior in each situation therefore Fire Eater cannot guarantee 100% protection of HDDs. For queries concerning technical matters, please contact the Fire Eater technical team.

All information given in this guide is done so in good faith. Fire Eater A/S cannot be held responsible for any errors or omissions and has the right to amend and update this document at will.

Silence is golden

Maintaining the integrity of HDD’s in a noisy situation

Maintaining the integrity of HDD’s in a noisy situation

Fire Eater A/S – Vølundsvej 17 – DK-3400 Hillerød – Tel: +45 7022 2769 Fax: +45 7023 2769 – info@fire-eater.com – www.fire-eater.com – CVR: 59538713 INDATBD010_Whitepaper _FE Silencer_UK.rev.01

Silence is golden

Maintaining the integrity of HDD’s in a noisy situation

TABLE OF CONTENTS 1 Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2 What harm can a little noise do? . . . . . . . . . . . . . . . . . . . . .

2.1 Why so harmful?. . . . . . . . . . . . . . . . . . . . . . . . . . .

2.2 Key findings from previous studies. . . . . . . . . . . . . . . . . .

3 Getting technical. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3.1 Scope of work. . . . . . . . . . . . . . . . . . . . . . . . . . . .

4 Testing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4.1 Test process. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4.2 Test result. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5 Conclusion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5.1 Reverberation . . . . . . . . . . . . . . . . . . . . . . . . . . .

5.2 Noise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6 FSN Silencer technology . . . . . . . . . . . . . . . . . . . . . . . .

6.1 Test outcomes . . . . . . . . . . . . . . . . . . . . . . . . . .

6.2 How it works . . . . . . . . . . . . . . . . . . . . . . . . . . .

6.3 Technical datasheet . . . . . . . . . . . . . . . . . . . . . . .

6.4 Standards. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7 References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8 Appendices . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

(1) Scope of work. . . . . . . . . . . . . . . . . . . . . . . . . . .

(2) Equipment used. . . . . . . . . . . . . . . . . . . . . . . . . .

(3) Test parameters . . . . . . . . . . . . . . . . . . . . . . . . . .

Fire Eater A/S – Vølundsvej 17 – DK-3400 Hillerød – Tel: +45 7022 2769 Fax: +45 7023 2769 – info@fire-eater.com – www.fire-eater.com – CVR: 59538713 INDATBD010_Whitepaper _FE Silencer_UK.rev.01

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Silence is golden

Maintaining the integrity of HDD’s in a noisy situation

1

Abstract

Recent studies have shown that the noise emitted by the discharge of clean agent automatic fire extinguishing systems is detrimental to the performance of enterprise hard drives and can lead to failure and possible data loss. Fire Eater FSN Silencers are specifically designed for easy installation over existing nozzles and have been shown to alleviate the risks to hard disc drives (HDD) due to noise.

The problem? Automatic clean agent fire extinguishing systems have been definitively shown to adversely affect HDD I/O performance during discharge due to noise.

The solution? Fire Eater’s FSN nozzle silencer, UL listed and LPCB approved.

The object of this paper is to explain the outcome of tests conducted by Fire Eater A/S during discharge of an INERGEN® extinguishing system in a simulated server room environment and how the use of FSN silencers within datacenter environments can help to mitigate noise induced damage to HDDs.

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Silence is golden

Maintaining the integrity of HDD’s in a noisy situation

2 What harm can a little noise do?

If the backbone of your business relied on datacenters in the year 2010 then every single minute of downtime would've cost approximately $5000. In the year 2013 that value increased to approximately $8000 per minute and increased again to $9000 in 20164. If a facility's capacity was rated at about 99% availability, then that translates into 3.65 days of accumulative downtime a year which costs approximately just over $47 million.

Ideally, an organization would shoot for 99.999% availability and many centers will claim to achieve those numbers but in reality this number may not be measuring service uptime but instead is measuring powered up time6.

The fact of the matter is many datacenters maintain an average RTO (Return Time Objective) of 2.86 hours which, unfortunately, is 65 percent larger than what's needed to continuously meet client demand5. This leads to the continuation of an organization’s availability gap. This goes without mentioning the reality of data loss for mission-critical applications which costs organizations on average $70,913 per hour5. Solid state drives (SSD) could be deployed as a means of mitigating the risks of noise to operating hardware and this may be a viable solution. However, enterprise hard drives will still remain competitive as they currently continue to gain capacity at a cheaper price as compared to SSDs7.

% 0 8 decrease in performance for hard drives $70,000 per hr = cost of data lost

Fire Eater A/S – Vølundsvej 17 – DK-3400 Hillerød – Tel: +45 7022 2769 Fax: +45 7023 2769 – info@fire-eater.com – www.fire-eater.com – CVR: 59538713 INDATBD010_Whitepaper _FE Silencer_UK.rev.01

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Maintaining the integrity of HDD’s in a noisy situation 2.1 Why so harmful?

Datacenters and their smaller counterparts are predominately protected by clean agent fire extinguishing systems. These systems usually use inert gases that would not adversely interact with the electronics in the rare case of a discharge.

Now, let's consider the fact that the progression of HDD technology has led to hard drive heads operating on much smaller scales in response to the increases in areal density. As purported by IBM experts, this has caused the decrease in spacing between data tracks. and in turn makes HDDs more susceptible to minute disturbances that impede reading or writing to disk.

Sound is merely the propagation of atmospheric disturbances through the air. Now, anyone that has been inside a server room or data center would take note on how incredibly loud those spaces are. If noise were the culprit, why didn't the issue manifest before? Well, if you have ever seen a singer shatter a glass with their voice, then you already have insight into the cause of the phenomenon.

The necessary conditions that must be met are frequency and intensity. In other words, it's the frequency that resonates with the crystal and it's the intensity of the sound that shatters it. The general background noise of a datacenter is neither at the proper frequency nor intensity to cause harm but during a fire extinguishing system discharge two things are: the sound of the alarms and the sound of the gas as it shoots out of the nozzle.

2.2 Key findings from previous studies The human ear has a common range of 20Hz to 20kHz, although given the uniqueness of humans there is considerable variation between individuals. The frequency range of a human voice is commonly 300 to 3500Hz, the intensity of which also varies. Sound intensities are normally expressed in dBa, Human ears are generally most sensitive in the range 3000 to 4000 Hz, below 500Hz and above 5kHz hearing sensitivity begins to diminish.

A 2015 study conducted by Siemens found that hard disks are not sensitive to frequencies below 500Hz while certain hard disks show sensitivity to noise between 500Hz and 1.6kHz1. The critical range of noise was found to be between 1.6kHz and 8kHz1.

To get a rough grasp of what these numbers mean, 500Hz is approximately the frequency of a small child's voice and 1.6kHz is a bit higher pitched than a whistle. The sounds between 1.6kHz and 8kHz are uncomfortable for a person to hear for even short periods of time. Whereas, the critical sound level sits approximately above 100 dB which is comparable to the sound of a helicopter flying 30m (100ft) above you.

We must also consider sound pressure levels (SPL) expressed in dB; 120 to 130dB is documented as the threshold of PAIN for most people.

When HDDs are exposed to a frequency, they will start to vibrate. If the frequency the HDD is exposed to is the same as that of the HDDs natural frequency a phenomenon called resonance will occur. Depending on the amplification factor of the HDD, the force as a result of the resonance can be up to 1000 times more than the force initially applied to the HDD. When a HDD is exposed to noise, there are two factors that will determine possible failure of the HDD: 1. The frequency that is applied 2. The sound pressure level that is applied A HDD may be able to withstand 140 dB if the frequency (band) is far from the resonance of the HDD component, whereas at a specific frequency (band) 110 dB may be sufficient to cause HDD failure.

In 2012 Tyco, IBM and Nelson Acoustics collaborated on an INERGEN® acoustics test involving the most common hardware and different test mockups of the most common nozzle distributions. This study also found the same conclusions as the Siemens study and both support the findings of an approximate average 80% drop in hard drive performance due to the specified range and intensity of noise2. Most of the hard drives were able to recover within about 2 minutes but a few completely failed and were effectively unsalvageable2.

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Silence is golden

Maintaining the integrity of HDD’s in a noisy situation

3

Getting Technical

The evolution of automatic fire extinguishing systems must follow in step with new discoveries and must readily adapt to properly suit the assets that they are entrusted to protect.

There is an armory of information and findings from studies completed by others within the fire industry in relation to the sensitivity of HDDs to noise. Taking IBM and Siemens findings into consideration we know that empirical data shows that HDDs exposed to noise levels above 110 dB1 begin to show performance degradation.

Fire Eater look to complement and add depth and breadth to this area of research. The hypothesis being that nozzle silencers can effectively mitigate noise levels created by an INERGEN® system discharge, to below critical levels where HDDs suffer from degradation.

3.1 Scope of work Test location description: The tests took place in an empty room of brick construction, with ceiling tiles and raised access computer floor above a solid substrate – essentially an empty datacenter.

We recognize that the empty room, with its flat, hard surfaces, will reflect the sound waves sharply. Much of the energy of the sound wave will be intact after the reflection. There will be considerable echo and this will affect the outcome negatively.

If the test location was populated with the assets and equipment that is normally found in a working datacenter, the sound waves would reflect and scatter around the room acting as a muffle and to a degree, kill the echo.

The room: ff ff ff ff ff ff

Empty Brick construction, ceiling tiles, raised floor tiles above solid substrate Volume of enclosure -4 x 627.4m3 Main room and floor void protected Normal operating temperature 20oC Nozzle mass flow 0.5 kg/sec

Fire Eater A/S – Vølundsvej 17 – DK-3400 Hillerød – Tel: +45 7022 2769 Fax: +45 7023 2769 – info@fire-eater.com – www.fire-eater.com – CVR: 59538713 INDATBD010_Whitepaper _FE Silencer_UK.rev.01

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Silence is golden

Maintaining the integrity of HDD’s in a noisy situation

4 Testing 4.1 Test process 1.

2.

3.

4.

5.

A fire is simulated by using smoke blocks. As soon as the smoke blocks are ignited data is recorded The INERGEN® system is released electrically Data is collected for 900 seconds (15 minutes post system release) The audio analyzer was situated 1m distance from the nozzle A datalogger connected to a laptop measures, oxygen levels, room pressure & room temperature

Datalogger

Audio Analyzer

4.2 Test result Highest noise levels recorded (dB): LAF max: 109.3 LA eq: 108.1 LCF max: 107.6 LC eq: 106.7 LZF max: 107.9

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Silence is golden

Maintaining the integrity of HDD’s in a noisy situation

5 Conclusion 5.1 Reverberation Reverberation is the collection of reflected sounds from the surfaces in an enclosure. The diagram below depicts the scenario of the direction of unbroken noise waves directly to the audio analyzer.

Nozzle As the enclosure was empty there was nothing in the room which could break the noise. The RT60 ( reverbaration time) value during the tests were recorded at 2.5 seconds.

A reference measurement should be made for comparison when the room is fully fitted.

Audio Analyzer

5.2 Noise Two peak levels of noise were recorded, with a maximum noise level of 107.0 dB. Previous tests conducted by Fire Eater, and in agreement with literature available on the subject of HDD noise sensitivity, show that reduced performance of the HDD’s will typically start around 110 dB. HDD failure has not been recorded under 120 dB+.

Thus concluding, that tests conducted in conditions with little reverberation prove that Fire Eater FSN Silencer nozzles serve to mitigate noise levels to a decibel that is below critical levels where HDDs suffer from degradation.

Fire Eater A/S – Vølundsvej 17 – DK-3400 Hillerød – Tel: +45 7022 2769 Fax: +45 7023 2769 – info@fire-eater.com – www.fire-eater.com – CVR: 59538713 INDATBD010_Whitepaper _FE Silencer_UK.rev.01

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Silence is golden

Maintaining the integrity of HDD’s in a noisy situation

6 FSN Silencer technology Fire Eater developed the FSN Silencer which minimizes noise and turbulence during system discharge. It is both UL listed and LPCB approved.

Specifically designed to work with the Fire Eater INERGEN® system, the FSN Silencer combined with a longer flow time, ensures that INERGEN® passes through the nozzle at a lower pressure resulting in a significant reduction in noise and turbulence.

6.1 Test outcomes

Result of testing a Fire Eater FSN Silencer Nozzle against a standard nozzle and old Silencer technology proves that the use of FSN Silencer technology produces a maximum reduction of 29 dB

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Maintaining the integrity of HDD’s in a noisy situation 6.2 How it works The FSN Silencer works by forcing the INERGEN® to pass through sound reducing mesh.

The INERGEN® has to travel further by going through the mesh and therefore lowering the dB at discharge.

The diagram illustrates the degradation of noise levels as the INERGEN® passes through the mesh layer.

Fire Eater A/S – Vølundsvej 17 – DK-3400 Hillerød – Tel: +45 7022 2769 Fax: +45 7023 2769 – info@fire-eater.com – www.fire-eater.com – CVR: 59538713 INDATBD010_Whitepaper _FE Silencer_UK.rev.01

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Maintaining the integrity of HDD’s in a noisy situation 6.3 Technical datasheet Chapter:

Engineering data sheet

61 - Nozzles

Page: 1 of 6

Sheet No.: IN-Silencers 2015

IN Nozzle Silencer Item numbers covered by this his datasheet datasheet 210125 210126 210128 210135 210136 210138 210123

IN-1/2" Silencer IN-3/4" Silencer IN-1" Silencer IN-1/2" Silencer FSN IN-3/4" Silencer FSN IN-1" Silencer FSN IN-1/2" Silencer 112 FSN

Related products 210203 IN-15 ISO Nozzle ø1-3 210204 IN-15 ISO Nozzle 210206 IN-20 ISO Nozzle 210208 IN-25 ISO Nozzle 210223 IN-15 npt Nozzle ø1-3 210224 IN-15 npt Nozzle 210226 IN-20 npt Nozzle 210228 IN-25 npt Nozzle The silencer is to be used with the above nozzles.

Item no. 210135

General The IN Nozzle silencer is designed as an add-on to Fire Eater INERGEN nozzles to protect equipment sensitive to acoustic noise, eg. hard discs and similar equipment.

Noise reduction of the different silencers is shown in table 2. The improved performance of the FSN (Flow System Nozzle) is achieved by letting the gas pass through the sound absorbing mesh in two stages.

The flow through the nozzle is not affected by the silencer, as Fire Eater’s calculation software IMT (which is UL listed and FM approved) is based on chocked flow across the nozzle. Adding the silencer to the nozzle does not change the choked flow, neither changes the pressure upstream of the nozzle orifice.

All data specification for the silencer is when used with Fire Eater mono-orifice nozzles.

Use of non-authentic Fire Eater nozzles in combination with the silencer is not advisable, unless it has been tested and verified by Fire Eater.

Document: IN-Silencers 2015

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Silence is golden

Maintaining the integrity of HDD’s in a noisy situation

Chapter:

Engineering data sheet

61 - Nozzles

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Sheet No.: IN-Silencers 2015

Specifications Temperature: -40 to +100 °C Materials: Aluminum and stainless steel Dimensions: ø130× 225 mm (112 model, ø130x 112.5 mm) Installation limitations (limitations not absolute, but verified to NFPA2001, UL2127, FM5600): Height Min. 0.3m (similar to FE mono-orifice nozzle) Height Max. 4.7m per row of nozzles Max coverage area: 7.32x7.32m (similar to FE mono-orifice nozzle) Connecting thread: Tapered pipe thread (ISO 7 or ASME B1.20.1 npt) Size as given in item description (1/2” to 1”) See table 1 for Mass of silencer, mass flow, noise Table 1 Item number

Marking

Dimensions Mass kg

Height mm

No silencer

Noise 0.65 Kg/s

1.27 kg/s

2.5 kg/s

118 dB

121 dB

120 dB

210125 210126 210128

IN-xx" Silencer

2.0

225

100 dB

100 dB

107 dB

210135 210136 210138

IN-xx" Silencer FSN

2.7

225

89 dB

92 dB

104 dB

210123

IN-1/2" Silencer 112 FSN

1.6

112

94 dB

100 dB

109 dB

Explanatory notes to noise recording in table 1 Noise recordings were performed inside a 19” rack measuring 600x1200x2000mm without sides and midway 2 servers and 4 blades (HDD) were installed.

Distance from the nozzle/silencer to the microphone was approx. 2m.

The room in which the 19” rack was placed, was constructed of plywood in accordance with NFPA 2001 and EN15004 with dimensions of 4800x4800x4700mm.

Reverberation time (RT60) for the room was Standard room: RT60 = 1.4 – 3.1 (63 hz to 4 kHz), W acoustic damping matr.: RT60 = 1.1 – 1.8 (63 hz to 4 kHz)

Marking Top: Fire Eater logo, “IN Silencer”, batch number Base: Fire Eater logo, “IN-xx Silencer”, batch number xx is the pipe thread size

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Chapter:

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61 - Nozzles

Page: 3 of 6

Sheet No.: IN-Silencers 2015

Installation 1. The base is attached between the nozzle and the pipe system.

For installation, a Pz2 screwdriver can be used in the hole in the side of the base.

Nozzles with male thread: The base is screwed onto the nozzle thread.

The nozzle and base assembly is screwed into the pipe socket.

Item no. 210126

Nozzles with female thread: The base is screwed onto the pipe thread.

The nozzle is screwed onto the pipe thread.

Note: If tape is used as thread sealant, it must be applied after assembling the base to nozzle.

If paste or liquid sealant is used, it may be applied before assembling the base to nozzle.

The thread of the hole in the base is oversize and will screw beyond the normal thread engagement.

2. The silencer cylinder with contents is screwed on to the base.

For FSN models it is important to align the inner cylinder with the recess in the base and in the top.

To check if it is aligned in the top, gently press on the inner cylinder to feel the suspension from the wave spring.

Use a Pz2 screwdriver in the hole in the side of the base to prevent the base from unscrewing.

Note: The silencer cylinders are partly symmetrical and interchangeable.

The outlet of the FSN models MUST be at the same end as the nozzle in order to work as intended.

Standard silencers have the outlets at the opposite end of the nozzle.

Maintenance After discharge the steel mesh inside the silencer must be inspected, if deformed it must be replaced.

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Maintaining the integrity of HDD’s in a noisy situation

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Engineering data sheet

61 - Nozzles

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Sheet No.: IN-Silencers 2015

Section drawings Standard silencer

Recommended replacement parts Pos. Item Description 1 210380 IMN Silent Top T0 2 210381 IMN Silent Cylinder T0 3 210382 IMN Silent Mesh 4 210394 IMN-T2 1/2" Silencer Base 210396 IMN-T2 3/4" Silencer Base 210398 IMN-T2 1" Silencer Base

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Material Alu Alu SS Alu Alu Alu

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Maintaining the integrity of HDD’s in a noisy situation

Chapter:

Engineering data sheet

61 - Nozzles

Page: 1 of 6

Sheet No.: IN-Silencers 2015

IN Nozzle Silencer Item numbers covered by his datasheet 210125 210126 210128 210135 210136 210138 210123

IN-1/2" Silencer IN-3/4" Silencer IN-1" Silencer IN-1/2" Silencer FSN IN-3/4" Silencer FSN IN-1" Silencer FSN IN-1/2" Silencer 112 FSN

Related products 210203 IN-15 ISO Nozzle ø1-3 210204 IN-15 ISO Nozzle 210206 IN-20 ISO Nozzle 210208 IN-25 ISO Nozzle 210223 IN-15 npt Nozzle ø1-3 210224 IN-15 npt Nozzle 210226 IN-20 npt Nozzle 210228 IN-25 npt Nozzle The silencer is to be used with the above nozzles.

Item no. 210135

General The IN Nozzle silencer is designed as an add-on to Fire Eater INERGEN nozzles to protect equipment sensitive to acoustic noise, eg. hard discs and similar equipment.

Noise reduction of the different silencers is shown in table 2. The improved performance of the FSN (Flow System Nozzle) is achieved by letting the gas pass through the sound absorbing mesh in two stages.

The flow through the nozzle is not affected by the silencer, as Fire Eater’s calculation software IMT (which is UL listed and FM approved) is based on chocked flow across the nozzle. Adding the silencer to the nozzle does not change the choked flow, neither changes the pressure upstream of the nozzle orifice.

All data specification for the silencer is when used with Fire Eater mono-orifice nozzles.

Use of non-authentic Fire Eater nozzles in combination with the silencer is not advisable, unless it has been tested and verified by Fire Eater.

Document: IN-Silencers 2015

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Id:

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Rev:2014.12.05

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Fire Eater A/S – Vølundsvej 17 – DK-3400 Hillerød – Tel: +45 7022 2769 Fax: +45 7023 2769 – info@fire-eater.com – www.fire-eater.com – CVR: 59538713

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Silence is golden

Maintaining the integrity of HDD’s in a noisy situation

Chapter:

Engineering data sheet

61 - Nozzles

Page: 6 of 6

Sheet No.: IN-Silencers 2015

Principle of the silencer Standard Silencer Noise generated in the nozzle is reduced by the steel mesh as the INERGEN passes through it.

FSN Silencer The FSN silencer is based on the same components as the standard silencer but is having the INERGEN passing a longer way through the sound reducing mesh.

The drawing illustrates how the noise is reduced going through the mesh.

Standards & approvals The silencer is tested and approved as a component for use in fixed fire extinguishing system by BRE Global and LPCB in accordance with FprEN 12094-7:2010.

Extinguishing test and nozzle coverage area test are passed in accordance with NFPA 2001, UL2127, FM5600, EN15004 and LPS1230 and are included in these listings/approvals*.

For performance as noise reduction devices for use in fire extinguishing systems tests to protect HDDs have been made in cooperation with CNPP. * Some authorities (eg FM Global) do not accept components for fire extinguishing systems in aluminum due to the low melting temperature. Some of these will not accept electrically energized material in protected hazards (Class C or HHA) either.

The silencer is made of aluminum and the nozzle inside is made of brass. Should the aluminum silencer melt, the system integrity will remain intact due to the brass nozzle. If the temperature has reached the level where aluminum melts, the noise issue will no longer be relevant, as sensitive equipment will have been lost before this.

Local authority representatives have authority to accept the final solution with deviations in order to ensure proper operation of the facility.

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Maintaining the integrity of HDD’s in a noisy situation 6.4 Standards There are currently no technical standards relating to noise reduction however, Fire Eater’s extensive hard drive research and rigorous testing have shown that noise levels in excess of 120-130 dB may reduce and influence the data transfer rate and overall performance of HDDs. Activation of a fire extinguishing system not equipped with Fire Eater’s FSN Silencer technology is more likely to suffer HDD damage.

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Fire Eater A/S – Vølundsvej 17 – DK-3400 Hillerød – Tel: +45 7022 2769 Fax: +45 7023 2769 – info@fire-eater.com – www.fire-eater.com – CVR: 59538713

INDATBD010_Whitepaper _FE Silencer_UK.rev.01

Silence is golden

Maintaining the integrity of HDD’s in a noisy situation

7 References 1. Siemens

Silent Extinguishing Disruptions to hard disk drives caused by inert gas extinguishing systems analysis and measures for the safe operation of storage system.

2. Tyco INERGEN Acoustics Testing Position Paper 3. INERGEN Full-scale test Server room Denmark 4. Emerson 2016 Cost of Data Center Outages 5. Veeam Data Center Availability Report 2014 6. Tier Classifications Define Site Infrastructure Performance 7. Storage trends 2016: Storage priorities, cloud appliances and NAS vs object storage 8. Rudco 2016: Inert Gas Discharge, Noise Problematic

Fire Eater A/S – Vølundsvej 17 – DK-3400 Hillerød – Tel: +45 7022 2769 Fax: +45 7023 2769 – info@fire-eater.com – www.fire-eater.com – CVR: 59538713 INDATBD010_Whitepaper _FE Silencer_UK.rev.01

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Silence is golden

Maintaining the integrity of HDD’s in a noisy situation

8 Appendices (1) Scope of work The following calculation reference: ff IMT V2.2.3 We set out to do the following: ff To measure and record noise during the discharge of an INERGEN® system

(2) Equipment used (2a) System equipment INERGEN® system description ff Pipework ff 15 off 80 litre 300 bar cylinders ff 497.16 kg of IG-541 ff Ci IV8 system with Ci MT manifolds ff Orifice 1 x ø8.6mm, 1 x x ø9.2mm ff Ci IS8 activation ff 26 off Nozzles with FSN Silencers (per calculation software) Four identical INERGEN® systems (as above) were used for this test. For optimal ease of transition between systems they were each placed on separate pallets.

(2b) TEST EQUIPMENT

Datalogger Graphtec GL220

Analyzer NTi audio XL2 (sn A2A-10816-E0, FW3.10) Microphone NTi audio M4260 (sn 5755

(3) Test parameters Design concentration (MDC) 42.0% (12.15% Oxygen) Discharge time: 90 seconds - 31.6% (14.3% Oxygen) Standard applied: N/A

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Fire Eater A/S – Vølundsvej 17 – DK-3400 Hillerød – Tel: +45 7022 2769 Fax: +45 7023 2769 – info@fire-eater.com – www.fire-eater.com – CVR: 59538713

INDATBD010_Whitepaper _FE Silencer_UK.rev.01

www.fire-eater.com

Fire Eater A/S – Vølundsvej 17 – DK-3400 Hillerød – Tel: +45 7022 2769 Fax: +45 7023 2769 – info@fire-eater.com – www.fire-eater.com – CVR: 59538713 INDATBD010_Whitepaper _FE Silencer_UK.rev.01

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Fire Eater A/S – Vølundsvej 17 – DK-3400 Hillerød – Tel: +45 7022 2769 Fax: +45 7023 2769 – info@fire-eater.com – www.fire-eater.com – CVR-no.: 59538713