CEN/TS 17441:2020

Laboratory installations - Ventilation systems in laboratories

This document applies for the planning, design, installation and commissioning of ventilation systems in laboratories. It also applies for scientific classrooms in schools when equipped with a ventilation system.
The application of this document depends not on the term laboratory in its narrower sense but this document also applies also for laboratory-related rooms in which work with dangerous or health hazardous substances is performed.

Laboreinrichtungen - Lüftungssysteme in Laboratorien

Dieses Dokument gilt für die Planung, Auslegung, den Einbau und die Inbetriebnahme von Lüftungssystemen in Laboren. Es gilt auch für wissenschaftliche Fachräume in Schulen, soweit diese mit einem Lüftungssystem ausgestattet sind.
Die Anwendung dieses Dokuments ist nicht vom Begriff Labor im engeren Sinn abhängig, sondern es gilt auch für laborähnliche Räume, in denen Tätigkeiten mit Gefahrstoffen oder gesundheitsgefährdenden Stoffen verrichtet werden.

Installations de laboratoire - Systèmes de ventilation pour laboratoires

Le présent document s’applique à la planification, la conception, l’installation et la mise en service des systèmes de ventilation dans les laboratoires. Il s’applique également aux salles de classe scientifiques dans les écoles lorsqu’elles sont équipées d'un système de ventilation.
L’application du présent document ne dépend pas du terme laboratoire dans son sens le plus restreint, mais le présent document s’applique également aux salles associées à des laboratoires dans lesquelles sont réalisés des travaux avec des substances dangereuses ou nocives.

Laboratorijska oprema - Sistemi prezračevanja v laboratorijih

General Information

• Status: Published
• Publication Date: 07-Apr-2020
• ICS: 71.040.10 - Chemical laboratories. Laboratory equipment
• ICS: 91.140.30 - Ventilation and air-conditioning systems
• Technical Committee: CEN/TC 332 - Laboratory equipment
• Drafting Committee: CEN/TC 332/WG 4 - Fume cupboards
• Current Stage: 9060 - Closure of 2 Year Review Enquiry - Review Enquiry
• Start Date: 02-Dec-2023
• Completion Date: 02-Dec-2023
• Ref Project: SIST-TS CEN/TS 17441:2020 - Laboratory installations - Ventilation systems in laboratories

Overview

CEN/TS 17441:2020 - Laboratory installations - Ventilation systems in laboratories - is a CEN Technical Specification that guides the planning, design, installation and commissioning of ventilation systems in laboratories. Approved for provisional application in 2020, it covers not only conventional laboratories but also laboratory-related rooms and scientific classrooms where work with dangerous or health‑hazardous substances takes place. The document supports safe, effective and maintainable laboratory ventilation practice across design and operational phases.

Key topics and technical requirements

CEN/TS 17441:2020 addresses practical technical topics used by designers and operators, including:

• Tasks of the ventilation system and safety‑relevant operation considerations.
• Design and construction: general design criteria, air volumes, and design parameters for laboratory environments.
• Airflow and room air quality: principles for airflow within rooms and factors affecting indoor air quality.
• Supply air systems: requirements for system layout and the relationship between supply and extract air.
• Extract air systems: extract layout, ductwork, arrestment and filtration, exhaust fans, maintenance and repair.
• Types of extract air equipment: definitions and requirements for fume cupboards, local extract devices (articulated extract arms), microbiological safety cabinets (MSCs), ventilated storage cabinets, bench/underbench/floor extraction and equipment vent lines.
• Special topics: explosion protection, sound pressure level, and ventilation provisions specific to microbiology laboratories.
• Documentation and labelling: ventilation system information and room/lab labelling requirements.
• National regulations: informative annex summarizing country‑specific rules (e.g., France, Germany, Netherlands, Spain).

Practical applications

This Technical Specification is intended to be applied during:

• Design and specification of HVAC and extract systems for new or refurbished laboratory buildings.
• Commissioning and balancing of supply/extract air to ensure correct pressure cascades and containment.
• Selection and layout of extract air equipment for chemical fume control and biological containment.
• Maintenance programs and safety audits addressing filtration, exhaust routing and equipment vent lines.
• Educational settings where scientific classrooms incorporate dedicated ventilation for hazardous work.

Who should use this standard

• HVAC engineers and consultants designing laboratory ventilation.
• Architects and building services designers involved in lab projects.
• Laboratory managers, safety officers and facility managers responsible for operation and maintenance.
• Installers, commissioning engineers and regulators ensuring compliance with European practice.

Related standards

CEN/TS 17441 references and aligns with other standards such as EN 14175 (fume cupboards), EN 16798 (ventilation/indoor environmental parameters), and EN 12128 (containment levels for microbiology laboratories), providing a coordinated framework for safe laboratory ventilation.

Standards Content (Sample)

SLOVENSKI STANDARD
01-junij-2020
Laboratorijska oprema - Sistemi prezračevanja v laboratorijih
Laboratory installations - Ventilation systems in laboratories
Laboreinrichtungen - Lufttechnik in Laboratorien
Installations de laboratoire - Systèmes de ventilation pour laboratoires
Ta slovenski standard je istoveten z: CEN/TS 17441:2020
ICS:
71.040.10 Kemijski laboratoriji. Chemical laboratories.
Laboratorijska oprema Laboratory equipment
91.140.30 Prezračevalni in klimatski Ventilation and air-
sistemi conditioning systems
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

CEN/TS 17441
TECHNICAL SPECIFICATION
SPÉCIFICATION TECHNIQUE
April 2020
TECHNISCHE SPEZIFIKATION
ICS 91.140.30; 71.040.10
English Version
Laboratory installations - Ventilation systems in
laboratories
Installations de laboratoire - Systèmes de ventilation Laboreinrichtungen - Lufttechnik in Laboratorien
pour laboratoires
This Technical Specification (CEN/TS) was approved by CEN on 27 January 2020 for provisional application.

The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to
submit their comments, particularly on the question whether the CEN/TS can be converted into a European Standard.

CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS
available promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in
parallel to the CEN/TS) until the final decision about the possible conversion of the CEN/TS into an EN is reached.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 17441:2020 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Tasks of the ventilation system . 9
5 Design and construction of ventilation systems . 10
5.1 General . 10
5.2 Design criteria . 11
5.3 Air volumes . 12
5.4 Design parameter . 13
5.5 Airflow within the room . 15
5.6 Room air quality . 15
6 Requirements for supply air systems . 15
6.1 General . 15
6.2 Supply air system . 16
6.3 Ratio supply air to extract air . 16
7 Requirements for extract air systems . 16
7.1 Extract air layout . 16
7.2 Extract air ducts . 17
7.3 Arrestment and filter systems . 19
7.4 Exhaust fans . 19
7.5 Maintenance and repair. 19
7.6 Explosion protection . 19
8 Sound pressure level . 20
9 Ventilation systems in microbiology laboratories . 20
10 Ventilation system information and laboratory labelling . 20
Annex A (informative) National regulations on ventilation . 21
A.1 General . 21
A.2 France . 21
A.3 The Netherlands . 21
A.4 Germany . 21
A.5 Spain . 22
Bibliography . 23

European foreword
This document (CEN/TS 17441:2020) has been prepared by Technical Committee CEN/TC 332
“Laboratory equipment”, the secretariat of which is held by DIN.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
According to the CEN/CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Introduction
Operation of ventilation systems in laboratory buildings or in individual laboratory rooms requires
particular care and attention due to its safety relevance. This applies for users of ventilation systems as
well as for operators of laboratory buildings.
This technical specification supports design, planning, execution and maintenance tasks of these
ventilation systems. A special expertise with regard to the operation and function of laboratories and
the effectiveness of technical laboratory equipment is required, particularly because of the many
possible interfaces for extract air equipment relevant to safety.
1 Scope
This document applies for the planning, design, installation and commissioning of ventilation systems
in laboratories. It also applies for scientific classrooms in schools when equipped with a ventilation
system.
The application of this document depends not on the term laboratory in its narrower sense but this
document also applies also for laboratory-related rooms in which work with dangerous or health
hazardous substances is performed.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
EN 12128:1998, Biotechnology — Laboratories for research, development and analysis — Containment
levels of microbiology laboratories, areas of risk, localities and physical safety requirements
EN 12792:2003, Ventilation for buildings — Symbols, terminology and graphical symbols
EN 14175-2, Fume cupboards — Part 2: Safety and performance requirements
EN 14175-7, Fume cupboards — Part 7: Fume cupboards for high heat and acidic load
EN 14470-1, Fire safety storage cabinets — Part 1: Safety storage cabinets for flammable liquids
EN 14470-2, Fire safety storage cabinets — Part 2: Safety cabinets for pressurised gas cylinders
EN 16798-1, Energy performance of buildings — Ventilation for buildings — Part 1: Indoor environmental
input parameters for design and assessment of energy performance of buildings addressing indoor air
quality, thermal environment, lighting and acoustics — Module M1-6
EN 16798-3:2017, Energy performance of buildings — Ventilation for buildings — Part 3: For non-
residential buildings — Performance requirements for ventilation and room-conditioning systems
(Modules M5-1, M5-4)
CEN/TR 16798-4:2017, Energy performance of buildings — Ventilation for buildings — Part 4:
Interpretation of the requirements in EN 16798-3 — For non-residential buildings — Performance
requirements for ventilation and room-conditioning systems (Modules M5-1, M5-4)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 12792 and the following apply.
For the different types of air in a laboratory or in a laboratory building EN 16798-3:2017, Table 6,
applies.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp/ui
3.1
laboratory
workspace with associated areas, such as access and support areas, with specific technical
requirements for which ventilation may be required
Note 1 to entry: In a laboratory, tasks are usually carried out during which possible hazards or potential
sources of nuisance, e.g. due to substances or procedures, can be kept under control. A ventilation system is
usually essential for such a task and can also be necessary for environmental control.
3.2
useable laboratory floor space
floor space of a laboratory room or a laboratory area; not included as useable laboratory floor space are
constructionally separated corridors and areas used for writing or analysis of results with a separated
ventilation
Note 1 to entry: Areas for writing or analysis of results can be considered to be separated from the useable
laboratory floor space e.g. by a suitable directed air flow.
3.3
extract air equipment
laboratory equipment that requires specified extract air volumes for its proper function, e.g. fume
cupboards, safety storage cabinets and local extract devices (see 3.9) or safety workbenches with
extract air connection
Note 1 to entry: Extract air equipment may need constant, intermitting or a continuously changing (hereinafter
referred to as “variable”) extracted air. Knowledge of all extract air equipment of a laboratory (see 3.4 to 3.17.) is
important for balancing the air volumes of the ventilation system.
3.4
fume cupboard
protective device to be ventilated by an induced flow of air through an adjustable working opening
— with an enclosure designed to limit the spread of airborne contaminants to operators and other
personnel outside the device,
— offering a degree of mechanical protection, and
— providing for the controlled release of airborne contaminants
Note 1 to entry: A fume cupboard is a ventilated enclosure complying with the requirements specified in
EN 14175-2.
[SOURCE: EN 14175-1:2003, 3.1]
3.5
pressure cascade
process whereby air flows from one area, which is maintained at a higher pressure, to another area at a
lower pressure
3.6
recirculatory filtration fume cupboard
protective device able, by trapping specified pollutants, to exhaust air back to the room
[SOURCE: EN 14175-1:2003, 3.6 modified - “room” was deleted from “room air” in the definition]
3.7
air-extracted workplace
containment device with the required level of protection established by risk assessment
Note 1 to entry: An air-extracted workplace may be regarded as a form of extract air equipment. At an air-
extracted workplace, not all protective measures of a fume cupboard are achieved, e.g. physical protection against
splashes and splinters cannot be given.
3.8
air-extracted enclosure
extract air equipment for a specific local routing of air that usually meets one of the protective aims
named in 3.4, e.g. dilution of pollutants in the interior to avoid hazardous, explosive atmospheres
3.9
local extract device
extract air equipment for local routing of air, e.g. to extract air around appliances and open bottles or
drums, typically with a flexible hose routing or articulated extract arm
Note 1 to entry: Articulated extract arm is abbreviated often by AEA.
3.10
microbiological safety cabinet
MSC
ventilated enclosure intended to offer protection to the user and the environment from the aerosols
arising from the handling of potentially hazardous and hazardous microorganisms, with air discharged
to the atmosphere being filtered
[SOURCE: EN 12469:2000, 3.3]
3.11
equipment vent lines
pipework in a laboratory, usually under negative pressure (relative to atmosphere), for laboratory
equipment outlets without a significant extract air volume
Note 1 to entry: A relieving pipework (with pump that creates a vacuum) usually is extract air equipment.
3.12
ventilated storage cabinet
ventilated laboratory equipment to store and provide substances that may constitute toxic hazards or
may contribute to the fire load or other hazards
Note 1 to entry: Safety storage cabinets are extract air equipment as soon as they are operated with extract air.
This is the most frequent operating mode. For safety storage cabinets for flammable liquids, see EN 14470-1, for
safety storage cabinets for pressurized gas cylinders see EN 14470-2.
Note 2 to entry: Ventilated storage cabinets should generally comply with EN 14056.
3.13
ventilated animal enclosure
enclosure to house animals and to limit exposure to allergenic substances or to provide containment for
pathogens
Note 1 to entry: Individually ventilated cages (IVCs).
3.14
ventilated weighing workplace
workplace with directed air routing for weighing toxic substances without affecting the weighing
process with airflows
3.15
bench extraction
extract air equipment for a directed air routing above or on the side of a laboratory bench
Note 1 to entry: A bench extraction usually is executed as a hood to capture ascending gases or vapours, e.g. for
hydrogen or hot exhaust air, from e.g. analytical equipment.
3.16
underbench extraction
extract air equipment for a directed air routing below a laboratory bench
Note 1 to entry: An underbench extraction usually is executed to extract gases or vapours with a higher density
than air and can e.g. be carried out by means of a perforated worktop (downdraught bench).
3.17
floor extraction
extract air equipment where air is extracted at, close to or through a floor
Note 1 to entry: The floor extraction may stand alone in the room, be integrated into laboratory furniture or
embedded in floors or walls.
3.18
ventilation system for laboratories
totality of fix installed technical devices for supply and disposal of air in a laboratory room or
laboratory building
Note 1 to entry: Laboratory ventilation systems usually contain air intakes and outlets, piping and ducts for
ventilation purposes, dampers, valves, control devices, fans, sound attenuators, etc. The interface to the laboratory
furniture usually is at the scheduled ventilation connection of the respective laboratory furniture or in the wall or
ceiling intake and outlet of the laboratory (room).
3.19
air exchange rate
number of times per hour that the total volume of the air movement due to the ventilation system is
exchanged with outdoor air in comparison to the volume of the space
3.20
chemicals storage room
room that is particularly used to store or provide chemicals in closed vessels
Note 1 to entry: Collection rooms in schools are not regarded as chemicals storage rooms.
3.21
solvents room
room with special equipment for storage or provision of organic solvents and other substances with a
low ignition point in closed vessels
3.22
outdoor air
total volume or proportion of air entering the system or opening from outdoors before any air
treatment
[SOURCE: EN 16798-3:2017, Table 6 modified - “total volume or proportion of” was added in the
beginning]
3.23
supply air
airflow entering the treated room, or air from the system entering the room after any treatment
3.24
extract air
airflow leaving the treated room and entering the air treatment system
[SOURCE: EN 16798-3:2017, Table 6]
3.25
recirculation air
extract air that is returned to the air treatment system and reused as supply air
[SOURCE: EN 16798-3:2017, Table 6]
3.26
exhaust air
airflow leaving the extract air treatment system and discharged to the atmosphere
[SOURCE: EN 16798-3:2017, Table 6]
3.27
secondary air
airflow taken from a room and returned to the same room after any treatment
[SOURCE: EN 16798-3:2017, Table 6, modified - note has been removed]
3.28
separative devices
isolators, glove boxes and similar total containment devices
Note 1 to entry: See EN ISO 14644-7.
4 Tasks of the ventilation system
Ventilation systems in laboratories shall meet following requirements:
a) They shall dilute and remove small amounts of hazardous substances (gases, vapours, dust, and
aerosols) which can be released in laboratories to such an extent that health risks by inhalation are
avoided. Hazardous substances should be captured or contained as close to their point of origin as
possible, e.g. by extract air equipment;
NOTE The room air in the common area, usually from the floor to a room height of 2 m, is regarded as
accessible to breathing.
b) The ventilation system of a laboratory shall not only safeguard the room air exchange requirement
but also the spatial and temporary (e.g. in case of a variable air volume of fume cupboards or in
case of pressure variations) requirement of extract and supply air of laboratory equipment and
appliances (extract air equipment, see 3.3);
c) The air exchange requirement of a laboratory (room) may be covered by the air extracted from the
extract air equipment of this laboratory. In that case, additional extract air cannot be required
whilst the equipment is in use;
d) Additional ventilation equipment in a laboratory can also be operated in secondary air mode (see
3.27), for instance for heating or cooling as well as for filtration;
e) The room air quality shall be ensured in accordance with EN 16798-1. This particularly applies for
safeguarding of room air comfort according to the criteria stipulated in EN 16798-1, e.g. for
humidity, turbulences, air velocity and temperature;
f) Pressure cascades shall meet safety requirements against spread of potentially hazardous
substances;
g) If required, the ventilation system shall also meet any clean room standards specified;
h) If required, the ventilation system shall also meet any standards specified for reproducibility of
results.
5 Design and construction of ventilation systems
5.1 General
Requirements for the ventilation system of a laboratory result from the requirements of the laboratory
room, the extract air equipment that is connected to the ventilation system, the ventilation system itself,
the plant rooms in which the ventilation system is located, and possibly also from the shell of the
laboratory building.
When designing laboratory ventilation systems the following requirements shall be taken into account:
a) Safety requirements based on legal regulations that may result from the general utilization of the
laboratory, e.g. to avoid accumulation of small amounts of hazardous substances in the laboratory
room air;
b) Requirements related to the technical function resulting from the positioning, connection and
operation of extract air equipment, e.g. air exchange rate, control characteristics, reliability and
cross-currents;
c) Requirements that result from connecting extract air equipment with the ventilation system, e.g.
fire protection, corrosion resistance (special application fume cupboards), temperature resistance
and leak tightness of ducts, ease of maintenance, cleaning and access;
d) Room air conditioning requirements according to EN 16798-1 in so far as applicable. Meeting
safety relevant regulations may lead to deviations from EN 16798-1 [see 5.1a)]. Furthermore,
deviations may also be necessary due to room ventilation depending on the use, e.g. for cold storage
rooms, solvent storage rooms, clean rooms and laboratories where tolerance to air velocity or close
control may be required;
e) Requirements that result case by case from legal regulations and from design expectance for energy
efficiency of the laboratory building and especially of the ventilation system;
f) The air flow velocity in the ducts should be kept low due to energetic and acoustical reasons;
g) Some extract air equipment for special applications may require individual fans and ducts that are
sometimes operated independently, thus affecting the room air balance;
h) The potential toxicity of extract air and subsequent contamination of filter systems and heat
recovery devices and resulting (safety) requirements in respect of maintenance;
i) Requirements for room air conditions, e.g. temperature, relative humidity, air movement and their
stability;
j) Requirements for clean room class.
5.2 Design criteria
When designing ventilation systems, the requirements for ventilation and/or air conditioning of the
laboratory room and of the laboratory user shall be taken into account. This shall include the supply
and extract air volume flows required for fume cupboards and other extract air equipment. The
ventilation system shall be capable to follow temporal and variable extract air equipment within the
scope of their planned utilization. The room air requirements shall be maintained under those
conditions, e.g. differential pressures to the environment of the laboratory rooms being considered.
NOTE 1 Temporarily variable extract air equipment is e.g. fume cupboards with a variable air volume
according to EN 14175-6.
NOTE 2 The ratio of supply air to extract air will have important effects on relative room pressurization and
the control of movement of potentially hazardous substances.
In laboratories with special protection aims additional requirements may apply, e.g. a higher safety
level for genetic engineering laboratories (see Clause 9), isotope laboratories, microbiological
laboratories or animal laboratories.
NOTE 3 Clean environments are described in EN ISO 14644-1.
The above mentioned requirements usually can only be met by a combination of supply air system and
extract air system.
Mechanical supply air systems should only be omitted in situations involving low hazard activities
(such as some school laboratories) or those with intermittent, short-term, or occasional use. In these
situations the following shall be considered:
a) the risk assessment to be made by the laboratory’s operator has shown that no hazardous
concentrations may occur in the room air, and
b) national requirements for air exchange rates are met;
c) supply air is sufficient to feed extract air equipment.
5.3 Air volumes
5.3.1 General
The ventilation system should be capable of providing variable air volumes for the supply and extract
air in such a way, that reduced air volume flows, e.g. in times beyond the conventional laboratory hours,
are possible. However, the function of permanent extraction points, e.g. safety storage cabinets, shall
not be affected.
NOTE 1 For air exchange in safety storage cabinets, see EN 14470-1 and EN 14470-2.
NOTE 2 For separate extract air systems, see 7.1.2
5.3.2 Extract air flow
An important stage in the planning process of the laboratory ventilation system shall be the
establishment of the supply and extract air volume flows needed for the laboratory room(s) and for
laboratory related rooms such as
— chemicals storage rooms;
— solvent storage rooms;
— rooms for pressurized gas cylinder storage;
— temperature controlled rooms;
— storing positions of cryogenic gases;
as far as applicable.
Other factors may need to be considered such as:
— heat load;
— dilution / fresh air;
— contaminants such as
— chemicals;
— airborne particles;
— allergens.
There is no unique extract air volume flow or air exchange rate which would fit all kinds of laboratories
and the work performed therein. Therefore, following the elaboration of an operating concept and a
risk assessment, the extract air volume has to be calculated in a combined step taking into account:
— national laws, regulations and standards, as well as
— requirements of equipment, extracts of several kinds, air quality in accordance with EN 16798-1
and loads of substances or thermal loads.
The extract air flow then will be calculated on basis of the larger value and optimized by the result of
the operating concept and risk assessment.
5.4 Design parameter
5.4.1 Operating concept and risk assessment
Based on operation concept and risk assessment coincidence factors the loads by substances can be
estimated. The extract air flows, as calculated on basis of 5.4.2 and 5.4.3, can be optimized by use of
these factors.
The result may be a reduced extract air flow during permanent operating mode. If the laboratory is
operated with this air flow, this has to be documented clearly and has to be labelled within the
laboratory (see Clause 10).
If operation is considered on basis of operating concept and risk assessment – especially for research
facilities – future developments and requirements, as far as predictable and realizable, have to be taken
into account.
In case of non-foreseeable changes in use like e.g. in research laboratories, it is not recommended to
take lower extract air volume flows as planning criteria. The chosen planning criteria implies no
specification of the air exchange rate for the future operation.
5.4.2 National laws, regulations and standards
In some cases, the design of laboratory ventilation systems will be gov
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