Enviro ST1 User manual

ST1 Safety Weighing Enclosure
Operating instructions

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Imprint
These operating instructions are original operating instructions. The operating instructions
should be read carefully and followed. The basic prerequisite for safe handling and trouble-
free operation of the equipment is knowledge of the safety regulations and observance of
danger and warning notices. If the safety weighing enclosure or installed accessories are to
be used in a way not intended by the manufacturer, please contact us in advance so that we
can assess the risks involved.
Manufacturer
a1-envirosciences GmbH
Eichsfelder Str. 1
40595 Düsseldorf
Phone: + 49 211 758483 -0
Fax: [phone]
[e-mail]
Internet: www.a1-envirosciences.de
Copyright
Copyright © a1-envirosciences GmbH, Düsseldorf
These instructions are protected by copyright and are intended exclusively for the operator's
internal purposes. The instructions may not be handed over to third parties, reproduced in
any form - including excerpts - and the contents may not be used and/or communicated
without the written permission of the manufacturer, except for the operator's internal
purposes. Violations will result in compensation. Further claims remain reserved.

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Contents
Explanation of symbols ................................................................................................................................... 5
Warnings .......................................................................................................................................................... 5
General information on safety ........................................................................................................................ 6
Responsibilities of the staff ............................................................................................................................ 6
Information for safe operation ....................................................................................................................... 7
Safety instructions for installation, operation, modification and malfunctions .......................................... 8
Instructions for safe maintenance, servicing, troubleshooting .................................................................. 11
Unpacking ...................................................................................................................................................... 14
Location selection ......................................................................................................................................... 15
Installation by a1-envirosciences ................................................................................................................. 16
Filter units - Notes on installation ................................................................................................................ 16
Functional description........................................................................................................................................ 18
ST1 safety weighing enclosure structure .................................................................................................... 20
Options ........................................................................................................................................................... 21
System dimensions ....................................................................................................................................... 21
System configurations and accessories ........................................................................................................... 22
System with two-layer HEPA filter (option) ................................................................................................... 22
Filter unit with silencer (option) .................................................................................................................... 23
System with additional solvent filter (option) .............................................................................................. 23
Electrostatic discharge systems (options) ................................................................................................... 24
Double bag waste system (option) ............................................................................................................... 24
Printer table (option) ..................................................................................................................................... 24
Connection to the building's ventilation system via draught diverter ........................................................ 25
Special safety instructions ........................................................................................................................... 26
Instructions for working with ST1 safety weighing enclosures ............................................................. 28
Filter units ................................................................................................................................................ 29
Filter change (only by qualified personnel).................................................................................................. 30
HEPA filter ...................................................................................................................................................... 31
Carbon filter ................................................................................................................................................... 31
Alarm system ................................................................................................................................................. 32
Structure and function of the alarm system................................................................................................ 32
Switching on the alarm system .................................................................................................................... 35
Operating the alarm unit .............................................................................................................................. 35

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Alarm state and safe operating state .......................................................................................................... 38
Resetting the alarm ................................................................................................................................. 39
Manual testing of the sensor .................................................................................................................. 40
LED lamp .................................................................................................................................................. 40
Discharging the waste bags ............................................................................................................................... 46
Intended use of electrostatic discharge systems .................................................................................. 48
Occupational and operational safety when working with electrostatic discharge systems ..................... 48
Installation and commissioning ................................................................................................................... 51
Use of electrostatic discharge systems ....................................................................................................... 52
Carrying out the cleaning .............................................................................................................................. 55
Suitable cleaning agents .............................................................................................................................. 56
Basic safety instructions for maintenance and repair work ..................................................................... 57
Maintenance intervals .................................................................................................................................. 59
Troubleshooting ............................................................................................................................................ 60
Customer service .......................................................................................................................................... 61
Dismantling by a1-envirosciences ............................................................................................................... 62
Dismantling on your own initiative ............................................................................................................... 62
Technical data for ST1 series safety weighing enclosures ......................................................................... 63
Information for delivery and packaging ....................................................................................................... 63
Materials ........................................................................................................................................................ 63
Dimensions .................................................................................................................................................... 64
Constand Air Volume (CAV) ........................................................................................................................... 65
Consumption of complete System per hour ................................................................................................ 65
Technical data on peripheral devices .......................................................................................................... 66
System dimensions - Filter unit with HEPA filter or activated carbon filter ............................................... 69
HEPA filtration unit ........................................................................................................................................ 69
Carbon filtration unit ..................................................................................................................................... 69
Observed standards ...................................................................................................................................... 70
Work regulations ........................................................................................................................................... 70
Technical rules .............................................................................................................................................. 71
Test procedure .............................................................................................................................................. 71
Consumables for ST1 series safety weighing enclosures .......................................................................... 72
Spare parts .................................................................................................................................................... 72

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Information for the user
Explanation of symbols
Warnings
Please read these operating instructions carefully. We want to ensure that you use our safety
weighing enclosures effectively without suffering any damage to your health. Observing our
warnings will also ensure that you can use this product for as long as possible.
Explanation of symbols of warnings concerning personal injury:
Indicates a dangerous situation where there is an immediate danger to life or
serious injury if the respective warnings are not observed.
Indicates a hazardous situation where there is a possible risk of serious or
fatal injuries if the respective warnings are not observed.
Indicates a hazardous situation where there may be a risk of minor injury if the
respective warnings are not observed.
Explanation of symbols of warnings concerning damage to equipment or materials:
Indicates warnings that serve to prevent damage to equipment or materials.
Explanation of symbols for important information:
Indicates particularly useful information.
Danger
Warning
Caution
Attention
Note

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General information on safety
The equipment complies with the fundamental health and safety requirements for laboratory
equipment. These have been taken into account accordingly in the design and construction
of the equipment. The equipment is built in accordance with the legal regulations, directives
and recognised standards applicable at the time it is placed on the market. Nevertheless,
hazards to people, materials and the environment may arise during use if the warnings in
these operating instructions are not observed.
Responsibilities
Responsibilities of the operator
The operator should ensure that only persons work with the safety weighing enclosures who
are trained and instructed in the handling of the device and
 who are familiar with the basic regulations on occupational safety and accident
prevention;
 who can refresh the necessary knowledge of working with hazardous substances and
the handling of safety weighing enclosures periodically through training;
 who have read and understood the operating instructions with the safety regulations
and the warnings included in these operating instructions.
The operator should also ensure that maintenance work, especially on the electrical
equipment, is only carried out by qualified and trained personnel.
Responsibilities of the staff
All persons assigned to work on the equipment should be trained and instructed accordingly.
Before starting work, they should:
 know the basic regulations on occupational safety and accident prevention and
observe them for their own safety;
 have read and understood the operating instructions with the safety regulations and
the warnings in these operating instructions;
know and observe the work instructions of the operator.

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Regulations for safe use
 Safety devices must not be switched off or overridden. The equipment must not be
modified or converted without the written consent of the manufacturer.
 The equipment must only be used in enclosed rooms designed for this purpose.
 The equipment must only be operated in perfect condition without damage. Faults
and damage must be rectified immediately; in the meantime, the equipment must be
decommissioned.
Information for safe operation
Improper use may pose a serious risk to persons and property.
There is a risk of contamination if the safety weighing enclosures are handled
incorrectly. The hazardous substances used can contaminate people in the
vicinity of the equipment and the environment.
Warning of misuse
Warning of contamination

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Please observe the following general safety instructions:
 The information in these instructions will help you to work in a safe and
contamination-free manner.
 Please read these instructions with particular care before working in the safety
weighing enclosure for the first time.
 Keep the instructions handy. When working on the ST1 weighing enclosure, ensure
that the instructions are also available there. a1-envirosciences recommends creating
an SOP for working on the ST1 weighing enclosure.
 These instructions assume that the user is familiar with all relevant directives, the
regulations "Safe working in laboratories" and working on technical equipment.
 The ST1 weighing enclosure may only be operated by trained personnel with the
necessary basic technical knowledge.
 Personnel must be properly instructed and trained before working with hazardous
substances.
 The applicable safety regulations of your company have priority and must be complied
with at all costs.
 Work according to the work regulations given in the operating instructions. For your
own safety and for the protection of other employees, you must observe the
additional safety instructions given in these instructions in addition to the safety
regulations applicable to you.
 For any questions regarding the use of the ST1 safety weighing enclosure, always
contact the person responsible for it or a1-envirosciences.
Safety instructions for installation, operation, modification and malfunctions
There is an immediate danger to life in case of contact with live parts. If the
insulation is damaged, switch off the power supply immediately and arrange
for repair. Work on the electrical equipment should only be carried out by
trained, authorised personnel. Keep moisture away from live parts. This could
lead to a short circuit.
Dan
ger to life due to electric current

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Basically, the discharge electrodes are safe to touch. This means that touching the metal
tips of the discharge electrodes will not cause electric shock.
Substances as well as auxiliary and operating materials could cause damage
to health or the environment in the event of contact.
 Before starting any work with the equipment, observe the relevant work
instructions of the operator.
 Observe the safety data sheets of the substances used.
 Remember that the transfer of hazardous substances from the storage
location to the equipment and the disposal of contaminated waste also
involve risks.
 Wear required protective equipment (PPE = personal protective equipment).
Solvents can form explosive vapour/air mixtures. Dusts can form explosive
dust/air mixtures. An explosive atmosphere in conjunction with an ignition
source can lead to an explosion.
Solvents are highly flammable. Storage of flammable solvents in the
equipment is therefore not permitted.
Explosions or fires can lead to serious or fatal injuries.
 The equipment must not be used when the filter unit is switched off.
 Flammable liquid or gaseous substances must not be introduced into the
work area, except for the approved cleaning agents and solvents.
 Ignition sources must not be present in or brought into the work area during
cleaning.
 Dust formation in explosive concentrations in the work area must be
avoided.
Warning of contamination risks
Warning of explosion and fire hazards

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If mains switches are not accessible, the equipment cannot be switched off
quickly and safely when needed. Damage to the equipment is possible, or
other hazards may arise.
 Make sure that the mains switches are always freely accessible.
Highly variable or excessive ambient temperatures can cause condensation of
water in the filter unit or overheating.
 Operate the ST1 safety weighing enclosure at as constant an ambient
temperature as possible in the range of 5 to 40°C to avoid damage from
condensing water or overheating.
Improper maintenance, repair or modification work can lead to considerable
damage.
 Cleaning, assembly, disassembly, maintenance, adjustment and repair may
only be carried out by persons who are trained for these activities and who
know the possible dangers.
 Unauthorised modifications and alterations to the ST1 safety weighing
enclosure are not permitted for safety reasons.
 Only original parts and accessories specifically designed for the ST1 safety
weighing enclosure may be used. Any liability for damage caused by the use
of non-original parts or accessories is excluded.
Leave mains switch accessible
Damage due to condensation or overheating
Damage due to improper
intervention

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Instructions for safe maintenance, servicing, troubleshooting
 Observe general occupational safety rules and accident prevention regulations.
 Wear suitable personal protective equipment.
 Carry out prescribed maintenance and inspection work in due time or have it
carried out by our qualified and specially trained personnel.
 Before maintenance, servicing and repair work, the power supply must be switched
off and secured against being switched on again.
 Check loosened screw connections for tightness.
 After completion of the maintenance work, safety devices must be checked for their
function.
Main features
Figure 1 - ST1-1200 safety weighing enclosure

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The ST1 safety weighing enclosures prevent aerosols and/or dust from escaping from the
interior of the enclosure. People and the environment are effectively protected from
contamination when the equipment is used as intended.
The ST1 safety weighing enclosures are to be understood as a system with an integrated
extraction system as a closed design, as the leakage of hazardous substances into the air of
the room outside the weighing enclosure is prevented. Leakage of airborne substances is
prevented by convection and diffusion of the incoming air and the design of the working
opening.
The ST1 safety weighing enclosures have been exemplarily tested according to the
guidelines of the ISPE (Institute of Pharmaceutical Engineers) for their suitability for the safe
weighing of smaller sample quantities of hazardous substances. The exposure control limit
(ECL) tested for weighing and small-scale handling of hazardous substances in quantities of
up to 1 g is less than 20 ng/m³.
The special features of the ST1 safety weighing enclosures are:
 Low-turbulence, horizontal air flow over the entire work area
 Specially shaped edges to guide air in the edge sections to prevent contaminated air
from escaping
 Ergonomically shaped arm bar
 Easy-to-clean cover of the air collection chamber
 Independent, separate filter housing to avoid vibrations in the weighing enclosure and to
maintain the scale functionality
 HEPA filtration system for safe, low-contamination filter changes
 Alarm system with two flow sensors
 Chemical-resistant ceramic work surface
 Waste system with inner and outer waste bag for contamination-free waste disposal

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Intended use
The ST1 safety weighing enclosures are used exclusively for weighing or other manipulations
of hazardous substances that pose a risk to persons and the environment in the event of a
release.
Observance of these operating instructions is part of the intended use. In the case of other
manipulations, we as a manufacturer offer support with an appropriate risk analysis.
Through his own risk assessments and operating instructions, the operator must ensure that
the equipment is only used within the limits of its technical specifications and that only work
is carried out and substances processed with it for which the equipment is suitable.
The ST1 safety weighing enclosures may only be installed and operated in an area in which
an explosive atmosphere is never present as a mixture of air and flammable gases, vapours
or aerosols or in the form of a cloud of combustible dust contained in the air (non-ATEX zone
according to EC Directive 94/9/EC).
The operator must ensure that no substances are processed in the work area in quantities
that could lead to the formation of an explosive atmosphere.
This must also be observed when cleaning the ST1 weighing enclosure with flammable
solvents that could lead to the formation of an explosive atmosphere.
During cleaning with these solvents, it is essential that the safety weighing enclosure and the
filtration and ventilation systems are switched on!
The ST1 series complies with the protective measures required by TRGS 500 (Technical
Rules for Hazardous Substances) and is to be regarded as a highly effective extraction
system. It is suitable for personal protection in accordance with EN 14175-3 for fume
cupboards and also complies with the ASHREA 110 standard.
The ST1 series has been tested according to EN 689 and ISPE guidelines with surrogate
substances by InfraServ GmbH & Co. Höchst KG. (The test protocol can be found in
appendix D).
The HEPA filtration system used is certified according to DIN/EN 1822.

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Assembly and installation
Unpacking
All a1-envirosciences products undergo extensive quality control before leaving the factory
and are carefully packed.
After delivery, check the packaging and contents immediately for signs of visible damage due
to improper handling during transport.
Until commissioning by a1-envirosciences, you should keep all components in their
packaging. During installation, all components are unpacked and set up by
a1-envirosciences.
If you unpack the components yourself (not recommended), please ensure that all
accessories are included. Keep the original packaging in any case as it offers optimum
protection if the components have to be returned, for example.
Always lift the ST1 weighing enclosure by grasping it under the base plate.
 Never lift it by the arm bar or the side openings.
Otherwise, the arm bar may be damaged or the base plate may detach from
the enclosure.
The ST1 safety weighing enclosure weighs 30-90 kg. There is a risk of injury
when lifting.
 It must be moved by two persons or by means of a lifting tool.
Avoid damage to the equipment during handling
Risk of injury
-
Caution: heavy weight

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Location selection
The installation location of the ST1 safety weighing enclosure has a direct
effect on the functionality of the safety weighing enclosure as well as on the
application installed in it. Please note the information below when selecting a
location.
 Little through traffic and draughts through ventilation systems, windows or corridors
as otherwise transverse flows could develop in front of the work opening, obstructing
the low-turbulence airflow into the enclosure.  Danger due to substance leakage!
 Even, stable and vibration-decoupled, vibration-free substructure to maintain the
functionality of the analytical balances used (if one is used).
 Good visibility and lighting must be ensured at the installation site.
 Clean and, if necessary, decontaminated set-up area. The installation location must
not be chemically, physically or biologically contaminated.
 The front of the ST1 weighing enclosure must be as close as possible to the weighing
table so that the arm bar protrudes slightly to allow good airflow to the flow sensors
(not required for IE series).
 A comfortable chair suitable for laboratory use with an upright backrest and height
adjustment should be provided as an integral part of the work area.
a1-envirosciences recommends adjusting the seat height according to body size so
that the forearms are approximately at a right angle to the upper arms in the working
position.
 The scope of delivery of the ST1 safety weighing enclosure includes a ventilation kit
that connects the weighing enclosure to the filter unit. The ventilation hoses
contained in it must not be kinked and come in contact with the ST1 safety weighing
enclosure and must be freely accessible.
 If the ST1 safety weighing enclosure is to be connected directly to the building's
exhaust air system (not recommended), an adjustable valve must be installed in the
system to regulate the air flow and to ensure the required inflow velocity (0.35-0.45
m/s).
 Special care must be taken with ST1 safety weighing enclosures that are connected
to a building's exhaust air system if gases, aerosols and/or particles are released and
exhausted into it. Here, special attention must be paid to the chemical compatibility
of the substances in the various exhaust air system ducts.
Attention: location selection

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Installation by a1-envirosciences
The ST1 safety weighing enclosure must only be installed by a1-envirosciences
service personnel or personnel specifically authorised for this purpose.
Installation by a1-envirosciences is included in the delivery.
The a1-envirosciences technician checks the installation location, unpacks the ST1
safety weighing enclosure and sets it up. All supplied options will be installed properly. A
power socket must be available and accessible near the installation location. (If an
antistatic bar is used, a second mains connection must be available.)
This is followed by a functional check of the sensors, the alarm system and the HEPA
filtration system. The HEPA filter's retention rate is tested by means of a DOP test
(Dispersed Oil Particulate). After successful installation, the customer receives an IQ and
OQ.
Finally, the users are instructed in the operation of the enclosure.
Furthermore, a1-envirosciences recommends an optional detailed training by a
specialised a1-envirosciences employee.
Filter units - Notes on installation
The filter unit must be positioned from the ST1 safety weighing enclosure in a vibration-
decoupled manner. The installation location can be under or above the enclosure or on the
side. The filter unit must not be installed upside down.
The hose connections to the filter unit should not come in contact with the ST1 safety
weighing enclosure (vibration transmission and thus impairment of the scale functionality).
Installation by a1-envirosciences is included in the delivery. When the filter unit is installed
by a1-envirosciences, the inflow velocity is set and recorded in the IQ/OQ.
A considerable risk of contamination arises if the filtration system is installed
incorrectly or functioning improperly!
 The filtration system may only be installed by a1-envirosciences or specially
authorised personnel. Installation by a1-envirosciences is included in the
delivery.
Avoid damage to the equipment during installation
Warning of contamination risks

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 Improper installation may result in damage to the filter. Only a correct
procedure ensures that the filter is installed properly and can be changed
without contamination.
 Setting or adjustment of the inflow velocity may only be carried out by
a1-envirosciences technicians or authorised personnel. There is a risk of
contamination if the inflow velocities are not set correctly!
 After installation and after each change of the HEPA filter, the function (filter
integrity) of the installed HEPA filter must be checked. For this purpose, a
DOP test (Dispersed Oil Particulate) is carried out.
If a DOP test is not carried out, the functionality of the ST1 safety weighing
enclosure cannot be guaranteed and there could be a significant risk of
contamination.
 Once installed, a filter housing with a qualified HEPA filter must not be
moved or opened.
Easy access for regular maintenance and possible filter change must be
ensured.
Annual maintenance of personal protection enclosures is required either by
law or the operator, depending on the risk assessment of the hazardous
substances used.
a1-envirosciences strongly recommends having the unit serviced annually and
the HEPA filters replaced every 3 years.
Notes on maintenance and filter change

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System description
Figure 2 - ST1-1200 safety weighing enclosure on stainless steel table frame
Functional description
The ST1 series safety weighing enclosures protect the user from airborne hazardous
substances during the weighing process or other dusty manipulations. This protection is
ensured by:
 Alarm-supported monitoring of air flows;
 Low-turbulence air flow due to the ergonomic design;
 Work according to GLP regulations.
The aim is to virtually eliminate the user's exposure to hazards. The design of the ST1 series
safety weighing enclosures guarantees highly effective extraction as the hazardous
substances remain within the detection area. The leakage of hazardous substances into the
ambient air of the ST1 safety weighing enclosure is virtually eliminated.

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The ST1 safety weighing enclosures work with a low-turbulence air flow which enables
optimum interaction between the scale and the enclosure. Extraction and filtration are done
by a separate filter unit, separated from the enclosure to achieve good vibration decoupling
and to isolate the contaminated filter.
The ST1 series is designed to create a horizontal, low-turbulence airflow over the entire work
surface. The air flow transfers any exposures that may occur during weighing to the HEPA
filtration system which retains them. The resulting exhaust air is thus free of pollutants and
is fed back into the room. Alternatively, a connection to a house ventilation system (via
draught diverter) is possible.
The motor-driven filter housing ensures a constant air flow through the working opening into
the interior of the enclosure. Due to the constant air volume (CAV), no exposures can escape
through the work opening and endanger the user.
The air requirement of the ST1 safety weighing enclosure is low and uniform compared to
other exhaust systems. The constant volume requirement enables problem-free integration
into existing exhaust air systems.
The ST1 safety weighing enclosure is equipped with an H14 HEPA filtration system (high-
efficiency particulate air filter) which has a retention rate of at least 99.995%. It is suitable
for an operating time of up to 3 years (manufacturer's recommendation).
A visual and acoustic alarm is triggered when the air flow falls below a limit value defined on
the alarm system, for example when the front flap is opened.
Unique to the ST1 series safety weighing enclosures is the monitoring of the air flow with a
separate sensor on the outside of the work opening. In contrast to other systems where the
air flow is only measured in the exhaust air pipe, the ST1 safety weighing enclosure allows
the current conditions to be measured at the working opening.
The special frame construction of the work surface provides protection against leaking
liquids. In case of leakage of liquids in relatively small quantities, these are retained in the
enclosure. The double bag waste system (optional) with inner and outer waste bag enables
contamination-free discharge of waste from the inner area of the enclosure.
In addition, a special profile of the arm bar ensures optimisation of the air flow over the base
plate of the ST1 safety weighing enclosure and enables the air flow not to be interrupted
even under the arms. The area at the arm bar forms the transition between the safe and the
hazardous, potentially contaminated area. The arms can be supported on the arm bar to
allow ergonomic, relaxed working inside the ST1 safety weighing enclosure.
An ergonomic design is an important aspect, as the user can lean forward to the scale to
weigh even the smallest sample quantities. The bevelled front of the ST1 safety weighing

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enclosure allows an ergonomic sitting posture as well as an optimal view of the display of the
analytical balance. Thanks to the high interior area, the user has more freedom of movement
for pipetting and handling samples.
The performance of ST1 series safety weighing enclosures was tested with surrogate
substances. Corresponding test results can be requested from the manufacturer if required.
(see appendix E)
ST1 safety weighing enclosure structure
The standard system consists of the ST1 safety weighing enclosure, the ventilation kit and a
filter unit with HEPA filter. The HEPA filter used allows the air to be returned to the room or
the in-house exhaust system to be connected via a draught diverter.
1 ST1 safety weighing enclosure
2 Front flap for inserting larger containers or devices
3 Ventilation kit consisting of a flexible ventilation hose that connects the enclosure with
the filtration system.
4 Filter unit with HEPA filter
5 Air outlet to the room