Ventilation for buildings - Ductwork - Cleanliness of ventilation systems

Standard for cleanliness of ductwork systems to include design, commissioning and maintenance aspects.

Lüftung von Gebäuden - Luftleitungen - Sauberkeit von Lüftungsanlagen

Diese Norm gilt für Lüftungs  und Klimaanlagen und definiert die Kriterien für die erste Bewertung der Sauberkeit sowie die Reinigungsverfahren für diese Anlagen; die Überprüfung der Wirksamkeit der Reinigung gilt auch für Produkte, die EN 1505, EN 1506, EN 13053, EN 13180 und EN 13403 entsprechen und in Klima  und Lüftungsanlagen innerhalb des Anwendungsbereichs des CEN/TC 156 verwendet werden.
Diese Norm legt Anforderungen und Verfahren fest, die zur Bewertung und Aufrechterhaltung der Sauberkeit von Lüftungsanlagen erforderlich sind, darunter:
   Vorgehensweise bei der Bewertung des Reinigungsbedarfs (optisch, Messungen);
   Bewertungshäufigkeit (allgemeine Hinweise);
   Wahl des Reinigungsverfahrens;
   Vorgehensweise bei der Bewertung des Ergebnisses der Reinigung.
Diese Norm ist eine parallele Norm zu EN 12097, in der Anforderungen an die Maße, die Form und die Lage von Zugangsdeckeln für die Reinigung und Wartung von Luftleitungssystemen festgelegt sind.
Diese Norm ist als Übersichtsnorm mit informativen Anhängen ausgelegt, zu denen im Laufe der Zeit folgende Themen hinzukommen können:
   zentrale raumlufttechnische Geräte (zentrale RLT Geräte);
   Filter;
   Befeuchter;
   Luftleitungen;
   Luftdurchlässe.
Die Hauptzielgruppen dieser Norm sind Gebäudeeigentümer, Wartungs  und Instandhaltungsunternehmen, Endverbraucher sowie Beratungs  und Kontrollunternehmen.

Ventilation des bâtiments - Réseaux de conduits - Propreté des systèmes de ventilation

Cette norme concerne les systèmes de ventilation et de conditionnement d'air. Elle définit les critères d'évaluation initiale de la propreté et les procédures de nettoyage de ces systèmes. La validation de l'efficacité du nettoyage concerne aussi les produits conformes aux exigences des EN 1505, EN 1506, EN 13053, EN 13180 et EN 13403, utilisés dans des systèmes de conditionnement d'air et de ventilation définis dans le domaine d'application du CEN/TC 156.
Cette norme spécifie les exigences et les procédures nécessaires pour évaluer et entretenir la propreté de la ventilation, dont :
   comment évaluer le besoin de nettoyage (inspection visuelle, mesures) ;
   fréquence des évaluations (orientation générale) ;
   sélection de la méthode de nettoyage ;
   comment évaluer le résultat du nettoyage.
Cette norme est parallèle à la norme EN 12097, qui spécifie les exigences de dimension, de forme et de localisation des panneaux d'accès pour le nettoyage et les interventions techniques dans les réseaux de conduits.
Cette norme est conçue comme une norme générale avec des annexes informatives pouvant être complétées au fil du temps pour les sujets suivants :
   caissons de traitement d'air ;
   filtre ;
   humidificateurs ;
   conduit ;
   bouches d'air.
Cette norme est destinée principalement aux propriétaires de bâtiments, entreprises d'entretien, entreprises de maintenance, utilisateurs finaux et entreprises de conseil et de contrôle.

Prezračevanje stavb - Kanali - Čistoča prezračevalnih sistemov

General Information

Status
Not Published
Publication Date
07-Aug-2022
Current Stage
4098 - Decision to abandon - Enquiry
Start Date
12-Oct-2009
Completion Date
12-Oct-2009

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SLOVENSKI STANDARD
oSIST prEN 15780:2021
01-junij-2021
Prezračevanje stavb - Kanali - Čistoča prezračevalnih sistemov
Ventilation for buildings - Ductwork - Cleanliness of ventilation systems
Lüftung von Gebäuden - Luftleitungen - Sauberkeit von Lüftungsanlagen
Ventilation des bâtiments - Réseaux de conduits - Propreté des systèmes de ventilation
Ta slovenski standard je istoveten z: prEN 15780
ICS:
91.060.40 Dimniki, jaški, kanali Chimneys, shafts, ducts
91.140.30 Prezračevalni in klimatski Ventilation and air-
sistemi conditioning systems
oSIST prEN 15780:2021 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 15780:2021


DRAFT
EUROPEAN STANDARD
prEN 15780
NORME EUROPÉENNE

EUROPÄISCHE NORM

May 2021
ICS 91.140.30 Will supersede EN 15780:2011
English Version

Ventilation for buildings - Ductwork - Cleanliness of
ventilation systems
Ventilation des bâtiments - Réseaux de conduits - Lüftung von Gebäuden - Luftleitungen - Sauberkeit von
Propreté des systèmes de ventilation Lüftungsanlagen
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 156.

If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations
which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC
Management Centre has the same status as the official versions.

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.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.


EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 15780:2021 E
worldwide for CEN national Members.

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Contents Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 4
4 Symbols and units . 5
5 Criteria for cleanliness and assessment . 5
5.1 General . 5
5.2 Assessment of the need for cleaning . 6
5.3 Design and handing over information . 6
5.4 Determination of cleaning interval . 6
5.5 Assessment of the result of cleaning . 7
6 Methodology . 7
6.1 General . 7
6.2 Assessment of methodology . 9
6.2.1 General . 9
6.2.2 Inspection plan . 9
6.2.3 Evaluation methods of dust accumulation . 10
6.3 Cleaning plan . 10
6.4 Cleaning methods . 11
7 Evaluation and reporting . 11
7.1 General . 11
7.2 Evaluation of cleaning . 11
7.3 Cleaning report . 11
Annex A (informative)  Cleanliness quality Air ventilation systems . 14
Annex B (informative)  Example of cleaning plan for Air ventilation system . 17
Annex C (informative)  Air Handling Units – specific guidance . 20
Annex D (informative)  Specific guidance for Filters in Air Handling Units . 23
Annex E (informative)  Specific guidance for Humidifiers in Air handling units . 24
Annex F (informative) Ductwork – Specific installation guidance for Air ventilation
system. 25
Annex G (informative) Terminal devices and units – Specific guidance Air ventilation
system. 28
Annex H (informative) Measurement methods for dust accumulation - Air ventilation
system. 29
Annex I (informative)  European Vacuum test method for measuring Dust
Accumulation in Air ventilation systems . 32
Annex J (informative) Kitchen Extract Equipment – Specific guidance . 34
Annex K (informative) Wiping test method to Evaluate Cleanliness on Site . 41
Bibliography . 43

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European foreword
This document (prEN 15780:2021) has been prepared by Technical Committee CEN/TC 156
“Ventilation for buildings”, the secretariat of which is held by BSI.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 15780:2011.
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1 Scope
This document applies to both new and existing ventilation, air conditioning systems and kitchen
extract system and specifies the assessment criteria of cleanliness, cleaning procedures of these
systems. The validation of the effectiveness of cleaning applies also to products, which conform
to EN 1505, EN 1506, EN 13053, EN 13180 and EN 13403, used in air conditioning and
ventilation systems for human occupancy defined in the scope of CEN/TC 156. This document
does not apply to installations for industrial, medical and laboratory facilities.
This document specifies general requirements and procedures necessary in assessing and
maintaining the cleanliness of ducted ventilation, for air ventilation systems and kitchen extract
systems.
The main target groups of this document are specifiers of the cleanliness quality classes and
cleaning methods primarily system designers who also specify the system of access, building
owners, services companies, maintenance companies, end users and consultancy and control
companies.
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 12599, Ventilation for buildings - Test procedures and measurement methods to hand over air
conditioning and ventilation systems
EN 12792:2003, Ventilation for buildings - Symbols, terminology and graphical symbols
EN 14799:2007, Air filters for general air cleaning — Terminology
EN 12097, Ventilation for Buildings - Ductwork - Requirements for ductwork components to
facilitate maintenance of ductwork systems
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 12792:2003 and
EN 14799:2007 and the following apply.
3.1
acceptable cleanliness level
amount of dust or other contaminants not to be exceeded, according to the specified
measurement method
3.2
acceptable post-clean level
no loose dust or for kitchen extract equipment, adhered grease deposits are detected visually on
the duct surface after cleaning and the system can reach an acceptable cleanliness level according
to a defined measurement method
Note 1 to entry: In case of conflict (e.g. between the building owner and the user), or uncertainty
objective methods are needed to assess the cleanliness/dirtiness
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3.3
acceptable dust accumulation level (new ductwork)
acceptable cleanliness level on new ductwork as handed over from builder to user
Note 1 to entry: In practice this means the quantity of pollution which is deemed acceptable
3.4
cleanliness
state or level of pollution defined as acceptable according to specification and a particular
measurement method
Note 1 to entry: Cleanliness is not absolute, it is defined by limit values. Dirtiness is the exceeding of such
a defined limit value
3.5
cleanliness quality class
level of cleanliness quality standard to be applied to various buildings and type of system,
consisting of three levels
— A: Low
— B: Medium
— C: High
3.6
visual inspection
subjective method to evaluate cleanliness level of surfaces
4 Symbols and units
For the purpose of this document, the symbols and units given in EN 12792:2003 apply.
5 Criteria for cleanliness and assessment
5.1 General
This chapter refers to ducted ventilation, for air ventilation systems. Kitchen extract systems are
dealt within Annex J
The key issue is to design, build and maintain the whole ventilation system so that it can be kept
clean enough during the whole lifetime of the installation. The following requirements, as well as
the methodology described in Clause 6, applies to the ductwork but can be also applied to air
handling units (according to EN 13053) and entire systems (see EN 16798-3and Annex A of this
document) Therefore it is necessary to specify the cleanliness quality class from the beginning
and include in the specification both design and installation issues and means to maintain a
sufficiently clean ventilation system for the whole of the lifetime. The design and installation
issues shall include (as a minimum):
— cleanliness quality class;
— cleanliness criteria and measurement method;
— production of the system components;
— delivery to site;
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— site storage;
— installation;
— protection of components after installation;
— handing over the system according to EN 12599
NOTE Annex A presents, as a common classification, three classes of cleanliness, application examples
for ductwork, and recommendations for the frequency of regular inspections in accordance with EN 16798
part 17.
5.2 Assessment of the need for cleaning
Inspection of functionality and cleanliness of ventilation system is a part of proper maintenance
of the ventilation systems. Mostly the inspection of the cleanliness may arise from two purposes:
— to check if ventilation system is dirty and needs to be cleaned (exceeding of a “target level” of
cleanliness);
— to evaluate cleanliness after the cleaning work
NOTE The assessment methodology is presented in 6.2.
For existing buildings, the inspection shall include a study of the existing documentation and
recommendations to complete and update the documents.
Specific considerations for kitchen extract equipment, the frequency of cleaning should be
sufficiently frequent that grease deposit limits are not exceeded.
5.3 Design and handing over information
In the handing-over documents the cleanliness quality class, cleanliness criteria and
measurement methods shall be specified, recommendations for cleaning methods and guidelines
for reaching the points to be cleaned shall also be given.
The design information shall give consideration to the expected cleaning method. Where the
system has been designed to be cleaned by wet cleaning methods, warning regarding conditions
and restrictions of use should be given. For example, wet methods are applicable only where
ducts are sufficiently moisture-tight, internal surfaces are smooth, and slope and drainage
arrangements have been provided so that fluid and contaminant can be evacuated.
A sufficient number of access / cleaning doors shall be provided in the ductwork. Additionally,
special care shall be taken regarding obstacles to cleaning such as dampers, sound attenuators
etc., which are mounted in the ducts. In many cases additional cleaning doors are needed after or
before such obstacle. Requirements for location of and distance between access doors are
presented in EN 12097 and EN 16798-3.
5.4 Determination of cleaning interval
The cleaning interval shall in principle be defined by reference to the cleanliness or dirtiness of
the system. Cleanliness or dirtiness shall in the first instance be assessed visually and this may be
confirmed by means of measurement – see Annex A.
The inspection interval to determine the need for cleaning may be defined in the system
documentation in order to assist with maintenance planning or design considerations related to
cleaning methods.
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5.5 Assessment of the result of cleaning
Methods for assessment of the need for cleaning can be also applied for assessment of the result
of cleaning.
The preferred methods of post-clean verification are given in Annex A.
6 Methodology
6.1 General
This chapter refers to ducted ventilation, for air ventilation systems. Kitchen extract systems are
dealt within Annex J
Figure 1 presents a procedure to control and maintain cleanliness of ventilation system. It does
not include the design stages or selection and specification of the system, or any of its
components.
The system shall be first checked visually, both in assessing the need for cleaning and in
verification of the result of cleaning. Objective measurements are needed if the visual inspection
results in disagreement or uncertainty about cleanliness or need for cleaning. See Figure 1 for an
explanatory flow-chart.
Objective measurements may be defined in advance as part of the cleaning or inspection plan.
NOTE 1 REHVA Guideline and some national guidelines like VDI 6022 and FiSIAQ Guideline give more
detailed guidance on product selection and specification from the hygienic point of view.
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Key
1 control and maintenance of cleanliness of air handling 7 acceptable cleanliness level
system
2 commissioning 8 cleaning
3 periodic inspection 9 verification
4 visually clean 10 documentation
5 clearly unclean Y yes
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6 objective measurements N no
Figure 1 — Schematic flow chart for procedures to maintain cleanliness of ventilation
system
If the components are certified for cleanliness or the cleanliness after production is otherwise
verified, and if the cleanliness instructions are properly documented, the commissioning may be
reduced to checking the documentation and random checking of the system cleanliness
(compliance with the documentation). See also 6.2.2.
The methods applied for objective measurements and verifications need to be consistent so that
the result of inspection is acceptable and give reliable grounds for decision making to order
cleaning work of the system when needed. Verification after cleaning is needed for quality control
of the cleaning work, and to verify the cleaning result.
NOTE 2 Annex I describe the preferred method of objective measurements.
NOTE 3 An example of acceptable levels of cleanliness (or dirtiness) is explained in Annex G.
Objective methods are needed if any guidelines or demands on cleanliness are set in official or in
voluntary documents. The methods to evaluate the cleanliness vary, and thus target values given
for the cleaning shall be accompanied by a description of the measurement method.
6.2 Assessment of methodology
6.2.1 General
Assessment of the characteristics of the contamination of the system is important in order to
define the cleaning method to be used.
System components are considered to be polluted when visual inspection and analytical
verification (according Annex I) give evidence of unacceptable dust level, microbial, or other
contamination. Assessment will be carried out through inspection. Dust accumulation, the type of
pollutants, such as “bacterial growth should determine the need for cleaning, cleaning methods
to be used and the required environmental controls.
Elements to be inspected for cleanliness start from the outdoor air intake and should include at
least:
— Air Handling Units (AHU’s). AHU’s assessment should include all their components and
sections: outdoor air intake, any mixing sections fan section, filters, plenums, heating and
cooling coils, condensate trays, sound attenuators, heat recovery section, and humidifier
section including droplet eliminators;
— supply air ductwork, including all types of terminal devices and terminal units, sound
attenuators, duct-mounted heating and cooling coils, dampers and valves;
— extract air ductwork, including all types of components;
— return and recirculation ductwork, including all types of components;
— fresh air intake ductwork.
6.2.2 Inspection plan
The inspection plan consists of the following information:
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— review plan and reports, including cleanliness quality class and measurement methods;
— determining which systems will be inspected;
— determining where to inspect and sample (see note);
— choosing equipment and tools.
Additionally, the inspection plan describes the requirements of the specific qualification and
experience for inspectors before they are authorized to carry out inspection work. The
assessment frequency shall be specified.
For new buildings, the owner, specifier and builder may agree a particular inspection plan to suit
their requirements.
Recommendations for assessment frequency are given in Annex A. To obtain objective results a
representative number of samples from representative parts and sites in the ventilation system
should be selected for evaluation of the cleanliness of the whole system A good rule of thumb for
choosing sites or taking samples is to select areas where the dust deposits are obvious, or liable
to cause reduced indoor air quality (IAQ) For inspecting and sampling, the ventilation system can
be divided in two parts, the ductwork and the rest of the system. Before inspection or sampling,
the sites should be selected at random with the aid of the design documents. The sampling sites
in the ductwork should be selected from the main duct starting from the AHU, main ducts, and
branch ducts. The sampling sites should include straight duct lengths and ducts with changes of
direction or terminations. In the rest of the system, filters or humidifiers give usually a good
indication of the cleaning needs.
System cleanliness inspections should also make reference to other parts of the as described in
6.2.1, and with particular reference to critical components such as filters and wet areas.
6.2.3 Evaluation methods of dust accumulation
Different methods to evaluate cleanliness of ventilation systems are available. The simplest
methods are based on more or less subjective visual observation of the cleanliness of ventilation
system combined with use of some special instrumentation. The advanced techniques are able to
give relatively accurate results that are comparable to given limit values.
NOTE The various methods available are discussed in Annex H. In Annex A preferred measurement
methods and limit values are given which relate to various cleanliness quality classes, and to post-clean
verification of cleanliness.
6.3 Cleaning plan
If, as assessed according to 6.2, cleaning is needed, a cleaning plan shall be provided. The cleaning
plan shall include:
— a summary of the assessment including the list of the systems and parts that need to be
cleaned;
— detailed time schedule of cleaning;
— cleaning methods to be applied;
— description of how access will be gained to ducts and equipment not visible in the rooms
(ducts, air handling units);
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— list of components to be removed for cleaning, and components to be replaced (when
relevant);
— protection of the rooms in which the cleaning equipment is used;
— how and when the occupants are informed (including protection and safety considerations);
— microbiological considerations when relevant, including considerations for the use of
disinfection;
— criteria to assess the need for involvement of a specialist on microbiological issues; technical
data, including an estimate of the present level of dust and impurities, and target levels for
cleanliness after cleaning; see Annex A;
— evaluation methods for cleanliness after cleaning.
One example of technical cleaning plan is presented in Annex B.
6.4 Cleaning methods
Cleaning methods shall be sufficient to achieve the required level of cleanliness without damage
to the system, to building users’ health and safety, and to the environment generally.
7 Evaluation and reporting
7.1 General
This chapter refers to ducted ventilation, for air ventilation systems. Kitchen extract systems are
dealt within Annex J.
7.2 Evaluation of cleaning
The final evaluation of cleaning shall be made after all parts of the ductwork or system subject to
cleaning have been assessed as visually clean.
Objective verification of post-clean cleanliness shall be carried out where necessary or as a result
of dispute or uncertainty.
The methods and limit value for post-clean verification of cleanliness are given in Annex A and J
methods may be selected voluntarily by agreement of parties to a cleaning contract.
7.3 Cleaning report
A report shall be prepared and signed. The report shall include at least the following details:
Details of the company executing the cleaning:
— the address and name;
— name of the responsible person carrying out the cleaning;
— the date of the inspection, cleaning and evaluation.
Details of the object (building, ventilation system, etc.):
— the address, name, or other unique identifier of the property;
— the owner or manager of the building.
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List of the documents provided, including documentation of the product certificates and
manufacturer's or supplier's instructions, whenever available.
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Details of the systems inspected:
— physical descriptions of the systems subject to inspection and cleaning;
— inventory of equipment.
Methods and equipment used for cleaning, and assessment before and after cleaning (visual,
measured):
— results of assessment before cleaning;
— scope of cleaning (entire system/ part of system);
— results of assessment after cleaning;
— pictures from each defined sampling point - before and after cleaning;
— documentation of the methods and equipment;
— recommendations (inclusive recommended time for next assessment and cleaning).
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Annex A
(informative)

Cleanliness quality Air ventilation systems
A.1 General
This annex gives a summary of three cleanliness quality classes. It is a key issue to pay attention
to cleanliness in design of systems and especially in component selection and specification. It may
be modified to take better into account some existing national guidance. Application examples
are presented in A.2, and more specific applications in Annexes C, D and E. See Annex J for
Cleanliness quality classes for Kitchen extract ducts.
— The following four major contaminants from all components may deteriorate IAQ and should
be limited:
— residues of lubricant oils from duct manufacture;
— dust accumulated during manufacture and installation or debris from construction;
— dust accumulated during operation;
— deposited microorganisms, particularly when toxigenic species are present and conditions
are favourable for their survival and growth during storage, installation and operation.
A.2 Application in general
These levels of cleanliness quality class should be generally applied as follows:
Table A.1 — Typical applications of cleanliness quality classes
Quality Typical examples
Class
Low rooms with only intermittent occupancy
e.g. storage rooms, technical rooms
Medium offices, hotels, restaurants, schools,

theatres, residential homes, shopping
areas, exhibition buildings, sport
buildings, general areas in hospitals and
general working areas in industries
High Laboratories, treatment areas in hospitals
high quality offices,
A.3 Assessment frequency recommendation
Assessment frequency described on Table A.2 should be considered as the minimum
recommendations and the necessity of increasing them will depend on the environment
conditions, on the activity and on mechanical and human conditions in both building and its
surroundings.
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In most cases inspection frequency should be specified rather than cleaning frequency since
changing and unknown conditions may alter the actual required cleaning frequency. Inspection
should be regular, cleaning subject to inspection.
Table A.2 —Inspection intervals according to cleanliness quality class, in months
a
 AHU Filters Humidifiers Ducts Terminals
Low 24 12 12 48 48
Medium 12 12 6 24 24
High 12 6 6 12 12
a
Filters should be inspected and maintained according to the manufacturer’s recommendations, with these
intervals as the minimum ones.
Air handling units equipped with humidification or adiabatic cooling systems or located in mild
and wet weather conditions should be assessed at least twice a year, whatever the use of the
building.
A.4 Cleanliness class quality measurements
Air ventilation system:
The described vacuum test method detailed in Annex I is derived from the vacuum test method
whereby a gravimetric result is achieved – see Annex I for details of the European test method.
Annex K describes an additional test method.
This method is suitable for circular, flat-oval and rectangular sheet metal duct types.
For internally lined (or other irregular, porous surface) ductwork, the vacuum test method is not
applicable. Other methods such as gel tape method can be used. Further work is necessary to
establish comparable limit values using these methods, however voluntary agreements may be
made.
To comply wi
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