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Meeting and Exceeding High Performance

ASHRAE DL

Standards, Codes and Guidelines with Air-to-Air Energy Recovery Systems and Equipment

Presented byPaul Pieper, Eng., Marketing Manager, Venmar CES Inc.

Presenter BiographyPaul Pieper, Eng., has over 15 years of Sales and Product Management experience in designing high performance HVAC systems and equipment for commercial and industrial applications.

He holds a degree in Pure and Applied Science from Marianopolis College, a Bachelor of Engineering degree from the Department of Building, Civil and Environmental Engineering. Mr. Pieper is a member of the Quebec Order of Professional Engineers as well as the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) and the Canada and U.S. Green Building Council (CaGBC & USGBC) and

Meeting and Exceeding High Performance Standards, Codes and Guidelines

Air-to-Air Energy Recovery Systems and Equipment

(ASHRAE) and the Canada and U.S. Green Building Council (CaGBC & USGBC) and represents Venmar CES Inc. with the Air-Conditioning, Heating and Refrigeration Institute (AHRI) on the Air-to-Air Energy Recovery Ventilation Equipment Section.

Mr. Pieper is the former Chair of ASHRAE TC 8.12 Desiccant Dehumidification Equipment and Components, is an active member of ASHRAE TC 5.5 Air-to-Air Energy Recovery and is Distinguished Lecturer for ASHRAE. He is also a member of the U.S. delegation for the ISO Working Group developing a “Method of Test for the Performance of Heat Recovery Ventilators and Energy Recovery Ventilators” and a member of the Project Monitoring Subcommittee for the upcoming “ASHRAE Design Guide for Dedicated Outdoor Air Systems”.

Disclaimer

The views and opinions expressed in this presentation are strictly those of the author and do not necessarily reflect the views of

the American Society of Heating



the American Society of Heating, Refrigerating and Air-Conditioning

Engineers (ASHRAE)

Learning Objectives

1. Understand the historical and current market drivers for energy recovery

2. Identify key current and proposed standards and guidelines that relate to energy recovery and determine where and why air to air energy recovery is mandated



where and why air-to-air energy recovery is mandated

3. Understand how energy recovery technologies may be used to resolve the seemingly conflicting requirements of current and proposed standards and guidelines

Ventilation Air

• The process of introducing outside air into occupied spaces for dilution of indoor pollutants

• Reduces occupant discomfort d l i t



and complaints

• A well-designed and ventilated area will result in high levels of human productivity and health

A Brief History of Energy Recovery

• Until the early 1970s, energy recovery was of little concern; mechanical ventilation rates were lower than today, but were supported by natural ventilation and IAQ was good



• The oil embargo, associated energy crisis and rapidly rising costs would have a profound effect on the design and operation of buildings throughout the world

Cause and Effect

Design Decisions• Reduced Amounts of O/A• Increasing Use of Synthetic Results



g yMaterials

• Tighter Building Envelopes• Reduced Productivity• Sick Building Syndrome (SBS) and

Building Related Illness (BRI)• Occupant Discomfort• Poor Indoor Environmental Quality (IEQ)

Response from the Market

• Standards were developed to improve IAQ, energy efficiency and human comfort

• Commercial energy recovery was introduced



gy yinto the commercial marketplace at this time as it proved to be one of the most economical ways to introduce ventilation air and improve IAQ

AAERV Applications

Pro

cess • Waste heat is

captured from the exhaust airstream & transferred to om

fort • Waste heat

captured from the process exhaust air stream heats the om

fort • Sensible and

latent energy are transferred from the exhaust air stream to the



Pro

cess

-to-

P the process supply airstream

• Equipment is available to handle exhaust temperatures as high as 1600°F

Pro

cess

-to-

Co

building makeup air during winter

• Typically modulated during warm weather to prevent overheating of makeup air

Com

fort

-to-

Co

supply air stream in summer and winter

• The objective is to temper the O/A with preconditioned air from the space

Energy Recovery VentilationGreen Building is Thriving in a Down Economy

• Climate Change, Energy Efficiency and the Global Economic Crisis

• Seemingly Conflicting and Increasingly Stringent Standards and Guidelines



Standards and Guidelines

• Net Zero Energy and Sustainability

• Energy Recovery Provides the Most Cost-Effective Way to Recycle Waste Energy and Create Quiet and Comfortable Indoor Environments

The Green EconomyEnergy Efficiency and the Economic Stimulus Package

• Allocation of $22 Billion Towards:

– Modernization of Schools’ Heating and Cooling Systems

– Conversion of Federal Buildings to High Performance Green Buildings



Green Buildings

– Energy Efficiency Projects, Energy Retrofits and Facility Modernization

• Funding for States is Dependent on Adopting an Energy Code at Least as Stringent as ASHRAE 90.1-2007

Selected Key Standards & Guidelines

• ANSI/ASHRAE Standard 55-2004 Thermal Environmental Conditions for Human Occupancy

• ANSI/ASHRAE Standard 62.1-2007 Ventilation for Acceptable Indoor Air Quality

• ANSI/ASHRAE Standard 84-2008 Method of Test for Air-to-Air Heat/Energy Exchangers

• ANSI/ASHRAE/IESNA Standard 90 1 2007 Energy Standard for Buildings



• ANSI/ASHRAE/IESNA Standard 90.1-2007 Energy Standard for Buildings Except Low-Rise Residential Buildings

• Proposed Standard 189.1P Proposed Standard for the Design of High-Performance, Green Buildings Except Low-Rise Residential Buildings

• ARI Standard 1060-2005 Performance Rating of Air-to-Air Heat Exchangers for Energy Recovery Ventilation

• LEED for New Construction and Major Renovations (LEED 2009)

ANSI/ASHRAE Standard 55-2004Thermal Environmental Conditions for Human Occupancy

PURPOSE:

To specify the combinations of indoor thermal environmental factors and personal factors that will produce thermal environmental conditions acceptable to a majority of the occupants within the space



ANSI/ASHRAE Standard 62.1-2007Ventilation for Acceptable Indoor Air Quality

Published in May, Standard 62.1-2007 supersedes Standard 62.1-2004 and incorporates Addenda a, b, c, d, e, f, g and h

PURPOSE:

To specify minimum ventilation rates and other measures intended to provide indoor air quality that is acceptable to human



air quality that is acceptable to human occupants and that minimizes adverse health effects

It is intended for regulatory application to new buildings, additions to existing buildings, and those changes to existing buildings that are identified in the body of the standard

It is intended to be used to guide the improvement of indoor air quality in existing buildings

Systems & Equipment Flow Chart



§ 5.10 Dehumidification Systems

§ 5.10.1 Relative Humidity

HVAC systems that have dehumidification capability must be designed to limit relative humidity toa maximum of 65% when analyzed under the following simultaneous design conditions:

At the peak outdoor dewpoint



At the peak outdoor dewpointdesign conditions and the mean coincident dry-bulb and

At the design indoor latent and sensible loads, and

With solar loads at zero.

This combination is the "dehumidification challenge"condition.

§ 6.1 Procedures

Indoor Air Quality Procedure• The IAQP is performance-

based

• The IAQP allows designers to take credit for source-control

Ventilation Rate Procedure• The VRP is prescriptive

• Outdoor air intake rates are predetermined for various space types (occupancy



take credit for source control and removal measures, such as selection of low-emitting materials and gas-phase air cleaning devices

space types (occupancy categories) based on contaminant sources and source strengths that are typical for the space type

Two-Component Approach

• Prescribed rates were expressed as volumetric airflow rate per person for most typical occupancy categories until about 2001

• This was significantly revised by



g y yAddendum 62n, approved by ASHRAE in June 2003 and ANSI in January 2004

• Additivity, now prescribes rates based on an occupant-related component and a building-related component

VRP Flow Chart



Estimating Outdoor Air



ASHRAE 62MZCalc

Ventilation Rate Reduction



Occupancy for outdoor air assumed to be 25 people / 1000 ft2

Ventilation Rate Comparison

Stan

dard

62.

1-20

01 Outside Air Requirements for Classroom Ventilation St

anda

rd 6

2.1-

2007 Outside Air

Requirements for Classroom Ventilation

Outside Air Reduction



ASH

RAE

S Ventilation

48,081 CFM

ASH

RAE

Ventilation

39,810 CFM

(17.2%)

§ 5.17 Air Classification & Recirculation

• Classifies air in various types of spaces

• Limits the recirculation of lower quality air into spaces that contain air of higher quality

• This requirement applies when using the



• This requirement applies when using the Ventilation Rate Procedure

§ 5.17 Air Classification & Recirculation § 5.17.1 Classification

Class 1: Air with low contaminant concentration and inoffensive odor and sensory-irritation intensity, suitable for recirculation or transfer to any



recirculation or transfer to any space.

Examples: Office spaces, classrooms, assembly rooms, churches, corridors


Class 2: Air with moderate contaminant concentration, mildly offensive odors or sensory irritation intensity, suitable for recirculation or transfer to any space with Class 2 or Class 3 air that is utilized for the same or similar purpose and involves the same or



similar purpose and involves the same or similar pollutant sources. Class 2 air is not suitable for recirculation or transfer to spaces with Class 1 air, or dissimilar spaces with Class 2 or Class 3 air.

Examples: Rest rooms, swimming pools, dining rooms, locker rooms, warehouses


Class 3: Air with significant contaminant concentration or significant offensive odor or sensory-irritation intensity that is suitable for recirculation with the same space Class 3 air is not



same space. Class 3 air is not suitable for recirculation or transfer to any other space.

Examples: Kitchens, dry cleaners, beauty salons, laboratories, pet shops.


Class 4: Air with highly objectionable fumes or gases or potentially containing dangerous particles, bioaerosols, or gases at a concentration high enough to be considered harmful



enough to be considered harmful, not suitable for recirculation or transfer to any other space.

Examples: Paint spray booths, laboratory fume exhaust, kitchen grease exhaust

§ 5.17.2 Re-Designation

A mixture is classified with the highest class of its constituents. For example, air returned from both a Class 1 and a Class 2 space served by a common system must be designated as Class 2 air

Formerly Known as Addendum y to 62.1-2004



BUT§ 5.17.2.2 Energy Recovery

Energy recovery resulting in 10% or less cross-contamination from Class 2 or 5% or less from Class 3 does not affect the classification of Class 1 air.

ANSI/ASHRAE/IESNA Standard 90.1-2007Energy Standard for Buildings Except Low-Rise Residential Buildings

PURPOSE:

The purpose of this standard is to provide minimum requirements for the energy-efficient design of buildings except low-rise residential buildings.

SCOPE:

This standard provides minimum energy efficiency requirements for the design and construction of



requirements for the design and construction of new residential dwelling units and their systems, and where explicitly specified, new portions of residential dwelling units and their systems, and new systems and equipment in existing dwelling units.

This standard applies to the building envelope, heating equipment and systems, air-conditioning equipment and systems, domestic water-heating equipment and systems, and provisions for overall building design alternatives and trade-offs.

90.1 Compliance Paths

§ 6 Heating, Ventilating and Air Conditioning



§ 6.5 Prescriptive Path

Economizers

Simultaneous heating and cooling

Air system design and

Heat rejection equipment

Exhaust Air Energy Recovery



Air system design and control

Hydronic system design and control

y

Exhaust hoods

Radiant heating

Hot gas bypass limitation

§ 6.5.2.3 Simultaneous Heating & Cooling

• Active dehumidification is most often required in humid climates so that air delivered to the space is not overcooled

• Is allowed in 90.1 if at least 75% of the energy for



gyreheating comes from site recovered or a site-solar energy source

Pre-Cooler Re-Heater Examples

Fixed Plate Heat Exchanger



Heat Pipe Heat Exchanger

§ 6.5.6.1 Exhaust Air Energy Recovery

“Individual fan systems that have both a design supply air capacity of 5000 CFM or greater and have a minimum outdoor air supply of 70% or greater of the design supply air quantity shall have an energy recovery system with at least 50% recovery effectiveness. Fifty percent energy

ff ti h ll h i th th l



recovery effectiveness shall mean a change in the enthalpy of the outdoor air supply equal to 50% of the difference between the outdoor air and return air at design conditions. Provision shall be made to bypass or control the heat recovery system to permit air economizer operation as required by Section 6.5.1.1.”

§ 6.5.6.1 Exhaust Air Energy Recovery

EXCEPTIONS:

Laboratory systems:

a. Systems serving spaces that are not cooled and that are heated to less than 60°F

b. Systems exhausting toxic, flammable, paint or corrosive fumes or dust

c. Commercial kitchen hoods used for collecting and removing grease vapors and smoke



and smoke

d. Where more than 60% of the outdoor air heating energy is provided from site-recovered or site-solar energy

e. Heating systems in climate zones 1 through 3

f. Cooling systems in climates zones 3c, 4c, 5b, 6b, 7 and 8

g. Where the largest exhaust source is less than 75% of the design outdoor air flow

h. Systems requiring dehumidification that employ energy recovery in series with the cooling coil

Proposed Addendum e to 90.1-2007Third Public Review Draft

• This is an ISC to the second public review of addendum e to incorporate changes suggested by the second public review comments

Revises section 6 3 2 and



• Revises section 6.3.2, and 6.5.6.1 and deletes a reference to Chapter 12 to include ARI 1060-2005 – Performance Rating Of Air to Air Heat Exchangers For Energy Recovery Ventilation Equipment Standard

Addendum e§ 6.3.2 Criteria and Requirements of § 6.5.6.1



Addendum eTable 6.5.6.1 & Climate Zones



Addendum eTable 6.5.6.1B & Normative Reference



ANSI/ASHRAE Standard 84-2008Method of Test for Air-to-Air Heat/Energy Exchangers

SPC 84-2008 - Revision project committee authorized 2/01/1995 with revised TPS. Revised TPS approved June 23, 2007 (Long Beach).

PURPOSE:

• To establish a uniform method of test



test

• Specify the test conditions, data required, uncertainty analysis to be performed, calculations to be used, and reporting procedures

• Specify the types of test equipment for performing such tests.

• Is NOT a Ratings Program

ARI Standard 1060-2005Performance Rating of Air-to-Air Heat Exchangers

for Energy Recovery Ventilation

PURPOSE:

To establish definitions, test requirements, rating requirements, minimum data requirements for Published Ratings, marking and nameplate data and conformance conditions for Air-to-Air Heat Exchangers intended for use in Air-to-Air Energy Recovery Ventilation Equipment



Energy Recovery Ventilation Equipment

ARI Certification Program started in Q1 2001

Old New

=

Standard Rating Conditions

Stringently tests for conformance and certifies the following to validate manufacturers claims with airflow at 75% and 100% of rated flow:

1 P D



1. Pressure Drop

2. Energy Transfer Effectiveness (Sensible, Latent and Total)

3. EATR (Cross Leakage)

4. OACF

Standard 1060 Key DefinitionsExhaust Air Transfer Ratio (EATR) & Outdoor Air Correction Factor (OACF)

Exhaust Air Transfer Ratio (EATR)

The tracer gas concentration difference between the Leaving Supply Airflow and the Entering Supply Airflow divided by the difference between the Entering Exhaust Airflow and the Entering Supply Airflow



Outdoor Air Correction Factor (OACF)

The Entering Supply Airflow divided by the measured (gross) Leaving Supply Airflow

Performance MetricsNet Sensible, Latent & Total Effectiveness

Net EffectivenessThe measured Effectiveness adjusted to account for the leakage of Entering Exhaust Airflow rather than exchange

AHRI Standard 1060



of heat or moisture between the airstreams

ARI 1060 versus 90.1 Effectiveness



ARI 1060-2005 ASHRAE 90.1-2007

Specification Verbiage

Manufacturer

Energy transfer ratings shall be ARI Certified to Standard 1060 and bear the ARI certification seal

Non-ARI Certified Manufacturer

The manufacturer shall provide certified performance data in accordance with ASHRAE



and bear the ARI certification seal for ARI Air-to-Air Energy Recovery Ventilation Equipment Program based on ARI 1060. Ratings "in accordance with 1060" without certification shall be deemed unacceptable.

accordance with ASHRAE Standard 84 and ARI 1060. Independent performance test results shall be used to rate the product in accordance with the ARI Air-to-Air Energy Recovery Ventilation Equipment Program .

ARI Certified Componentshttp://www.ahridirectory.org



Proposed Standard 189.1PStandard for the Design of High-Performance, Green Buildings

• Currently being developed by ASHRAE, IESNA & USGBC

• In 3rd Public review

• Will be written in code language; upon completion it will become an ANSI-accredited standard that



an ANSI-accredited standard that can be incorporated into building codes

• A step towards sustainability and a glimpse at the at the future of Standards 90.1 and 62.1

What is 189.1P?

• 189.1P is NOT a design guide or ratings system

• Where LEED operates on a menu-system for compliance, 189.1P will have mandatory criteria in all categories with simple compliance options



g p p p

• Creates a baseline for sustainable design, construction and operations in order to drive green building into mainstream building practices

§ 7.4.3.8 Exhaust Air Energy RecoveryTable 7.4.3.8 Energy Recovery Requirement

DOE Climate Zones

189.1P Third Public Review Draft



• Mandates 60% Energy Recovery Effectiveness

• Replicates Addendum e but requires energy recovery from as little as 10% of design airflow

U.S. Green Building Council

The U.S. Green Building Council (USGBC) is a non-profit organization committed to expanding sustainable building practices. USGBC is composed of more than 15,000 organizations from across the building industry that are working to advance structures that are environmentally responsible, profitable and healthy places to live and work.



USGBC's Mission

To transform the way buildings and communities are designed, built and operated, enabling an environmentally and socially responsible, healthy and prosperous environment that improves the quality of life.

USGBC's Vision

Buildings and communities will regenerate and sustain the health and vitality of all life within a generation.

Energy & Atmosphere

Prereq 2Minimum Energy Performance

Required

ERV sys tems can be des igned or selected to meet

the mandatory (5.4, 6.4, 7.4, 8.4, 9.4 & 10.4) and

prescriptive (5.5, 6.5, 7.5, & 9.5) or performance

(Section 11) requirements of 90.1 ‐2007

Credi t 1Optimize Energy Performance

1 to 19

ERV sys tems can be used to help acheive

improvements over baseline bui ldi ng performance

for maximum energy optimiza tion to maxi mize ava ilabl e credits for this category; DOAS reduces

energy use and demand and results i n

approximately 30% reduction in mechnical system

opera ting costs; additional ai r‐to‐ai r energy recovery strategies and parall el system sel ecti ons

can achieve even more

Indoor Environmental Quality

Energy & Atmosphere

Prereq 2Minimum Energy Performance

Required


the mandatory (5.4, 6.4, 7.4, 8.4, 9.4 & 10.4) and

prescriptive (5.5, 6.5, 7.5, & 9.5) or performance

(Section 11) requirements of 90.1 ‐2007

Credi t 1Optimize Energy Performance

1 to 19

ERV sys tems can be used to help acheive

improvements over baseline bui ldi ng performance

for maximum energy optimiza tion to maxi mize ava ilabl e credits for this category; DOAS reduces

energy use and demand and results i n

approximately 30% reduction in mechnical system

opera ting costs; additional ai r‐to‐ai r energy recovery strategies and parall el system sel ecti ons

can achieve even more

Indoor Environmental Quality

LEED v3 / LEED 2009



Prereq 1 Minimum IAQ Performance Required


the minimum requirements of Secti ons 4 through

Section 7 of 62.1‐2007

Credi t 2 Increased Ventilation 1

ERV sys tems provide the most cost effective method of delivering 30% more ventila tion ai r while

maximi zing energy performance through the use of

a ir‐to‐a ir energy recovery technol ogies

Credi t 5Indoor Chemical & Pollutant Source Control

1

ERV equipment can be des igned or selected with MERV 13 filters and reduce the potentia l for

potentia l ly hazardous particul ate a gaseous

pollutants

Credi t 6.2Controllability of Systems , Thermal Comfort

1

ERV sys tems conti bute to this credit with

equi pment and controls tha t can provide

individua l comfort controls for 50% of occupants

Credi t 7.1 Thermal Comfort, Design 1

ERV sys tems can be des igned or selected to meet the requirements of ASHRAE Standard 55 ‐2004 for

tempera ture and humi dity that supports

productivity and well‐being quite eas ily wi th the

DOAS approch and appropria te parallel sys tem

selection

Prereq 1 Minimum IAQ Performance Required


the minimum requirements of Secti ons 4 through

Section 7 of 62.1‐2007

Credi t 2 Increased Ventilation 1

ERV sys tems provide the most cost effective method of delivering 30% more ventila tion ai r while

maximi zing energy performance through the use of

a ir‐to‐a ir energy recovery technol ogies

Credi t 5Indoor Chemical & Pollutant Source Control

1

ERV equipment can be des igned or selected with MERV 13 filters and reduce the potentia l for

potentia l ly hazardous particul ate a gaseous

pollutants

Credi t 6.2Controllability of Systems , Thermal Comfort

1

ERV sys tems conti bute to this credit with

equi pment and controls tha t can provide

individua l comfort controls for 50% of occupants

Credi t 7.1 Thermal Comfort, Design 1

ERV sys tems can be des igned or selected to meet the requirements of ASHRAE Standard 55 ‐2004 for

tempera ture and humi dity that supports

productivity and well‐being quite eas ily wi th the

DOAS approch and appropria te parallel sys tem

selection

EA Credit 1Optimize Energy Performance

OPTION 1 — WHOLE BUILDING ENERGY SIMULATION (1–19 Points)

Demonstrate a percentage improvement in the proposed building performance rating compared to the baseline building performance rating per ASHRAE/IESNA Standard 90.1-2007 (with errata but without addenda*) by a whole building project simulation using the Building

OPTION 2 — PRESCRIPTIVE COMPLIANCE PATH (1 Point)

Comply with the prescriptive measures of the ASHRAE Advanced Energy Design Guide appropriate to the project scope, outlined below. Project teams must fully comply with all applicable criteria as established in the Advanced Energy Design Guide for the climate zone in which



project simulation using the Building Performance Rating Method in Appendix G of the Standard.

Design Guide for the climate zone in which the building is located.

OPTION 3 — PRESCRIPTIVE COMPLIANCE PATH: Advanced Buildings™ Core Performance™ Guide (1-3 Points)

Comply with the prescriptive measures identified in the Advanced Buildings™ Core Performance™ Guide developed by the New Buildings Institute.

EQ Credit 2Increased Ventilation

CASE 1 - MECHANICALLY VENTILATED SPACES (1 Point)

Increase breathing zone outdoor air ventilation rates to all occupied spaces by at least 30% above the minimum rates required by ASHRAE Standard



62.1-2007 (with errata but without addenda*) as determined by EQ Prerequisite 1.

Ventilation Rate ComparisonEQ Credit 2 - Increased Ventilation (1 Point)

HRA

E St

anda

rd 6

2.1-

2007 Outside Air

Requirements for Classroom Ventilation*

LEED

200

9 /

v3 Outside Air Requirements for Classroom Ventilation



ASH

39,810 CFM 51,753 CFM30% Increase

* Based on total square footage of classroom area for the Baseline High School and assuming 25 people per 1000ft2 from the Technical Support Document: Development of the Advanced Energy Design Guide for K-12 Schools—30% Energy Savings

An additional 11,943 CFM of O/A needs to be introduced with 30% less energy!

Conclusions

• The use of air-to-air energy recovery technologies that is mandated in current minimum performance standards is rapidly increasing

• The current economic climate is providing strong incentives to use energy recovery beyond the minimum requirements currently required by codes



• Concerns for the environment and high performance building codes and guidelines will require air-to-air energy recovery in order to meet the seemingly conflicting requirements of high performance HVAC systems that are energy efficient and capable of delivering superior IEQ

• Air-to-air energy recovery systems and equipment provide some of the most cost-effective and efficient ways to recycle waste energy while creating quiet and comfortable indoor environments

Beyond this PresentationUseful References

ASHRAE: http://www.ashrae.org/

TC 5.5 Air-to-Air Energy Recovery: http://tc55.ashraetcs.org/

Advanced Energy Design Guides: http://www.ashrae.org/publications/ page/1604

AHRI: http://ari.org/

AHRI Certification



AHRI Certification: http://ari.org/Content/AirtoAirEnergyRecoveryVentilators_81.aspx

• 2004 ASHRAE Handbook – HVAC Systems and Equipment, Chapter 44 Air-to-Air Energy Recovery

• ARI Guideline V: ARI Guideline V: Calculating the Efficiency of Energy Recovery Ventilation and Its Effect on Efficiency and Sizing of Building HVAC Systems

• ARI Guideline W: Selecting, Sizing, & Specifying Packaged Air-To-Air Energy Recovery Ventilation Equipment (2005)

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