Operations and Maintenance ofLaboratory Ventilation Systems

D. Randall Lacey PECornell University

Outline

Why is O&M important

O&M Responsibilities

Current Topics inLaboratory Operation

Resources

DUCTS

FILTER

ROOF

FAN

STACK

SUPPLYAIR

ChemicalHoods

LocalExhaustHoods

SAFETY

THINK

LAB OFFICE

HVAC = 40% - 60%Operating Costs

$5 to $10 per cfm-yr

Lab Ventilation Overview

http://fumehoodcalculator.lbl.gov/index.php

Fume Hood Energy Model

Benefits of O&M

Increase safety

Save money

Enhance comfort andenvironmental quality

Free-up capacity

Strengthenmaintenance/reliability

Utilities

Custodial

Maintenance

$-

$5.00

$10.00

$15.00

$20.00

Geolo

gy

Chem

T&

R

Phys

ics

Engin

eerin

g

Bio

tech

Nano

Res

Chem

T&

R

Mate

rials

Chem

Res

Lab Building O&M Costs

Cost Trend in Maintenance

Strategies for an Effective O&M Program

• Provide a clear, accountable organizational structure.

• Conduct energy-use studies and implement efficiencyupgrades.

• Commit to implementing projects that are cost effectiveon a life-cycle basis.

• Ensure top performance with good maintenance.

• Manage utility costs, not just utility use.

• Encourage awareness and provide training.

• Track performance against baseline metrics.

Awaren

ess

Load

Mana

gem

ent

RateAna

lysis

Energ

yAud

its

Met

ers

Comm

issio

ning

/Tun

e-Ups

Ligh

ting

Ret

rofits

Building

Envelo

p

EMCS

Renewab

les

Chiller/B

oiler

Replac

emen

t

No Cost Low Cost Expensive

O&M Improvements

Equipment Replacement

Investment Requirements

The Energy Management Continuum

Maintenance Components – Academic Building

Maintenance Components – Research Building

Maintenance Variation – Research Building

Clark Hall 99/00 - 03/04

HVAC

$0

$10,000

$20,000

$30,000

$40,000

$50,000

$60,000

$70,000

$80,000

$90,000

$100,000

99/00 00/01 01/02 02/03 03/04

Sensors/Controls

Fume Hoods

Motors, Pumps & Fans

Distribution

O&M Responsibilities – Building Design

• Select consultants with proven lab experience

• Contract should include responsibilities for budget,

performance, LCCA

• Establish clear design criteria

• Require record drawings at completion

• Hire a Cx agent

• Conduct thorough in-house review at each stage

• LCCA for system options

• Investigate technologies new to your campus or

facility

• Specify training of major equipment

O&M Responsibilities – Building Construction

• Hire Cx agent for testing and inspection

• Listen to your Cx agent, run all problems to ground

• Use in-house maintenance staff for inspection

• Get your staff to vendor training

• Archive maintenance manuals, record drawings and

Cx reports

• Label major equipment

O&M Responsibilities – Ongoing

• Use maintenance management system that

schedules PM and tracks repairs

• Meter building energy use adjusting for rates and

climate

• Monitor energy use for increases

• Incorporate equipment and system experience into

design standards.

Current Topics in Laboratory Operation

Energy use and cost

Carbon footprint

Commissioning

Low flow hoods

Computational Fluid Dynamics (CFD)

Demand Controlled Ventilation

Chilled beams

Ventilation rate and control

Lab chemical classifications

Shared facilities

Maintenance cost reduction

The Typical Research Campus

Building Area = 13.5 million sf

Lab Buildings = 2 million sf

Utilities Budget ~ $70 million/yr

4 Million sf of lab buildings$5 /sf for utilities = $20 M$3/sf for maintenance = $12M

TOTAL O&M for Lab Buildings

$32 Million

0

100

200

300

400

0 5 10 15 20

1000

Tons

ofC

arb

on

/ye

ar

Million GSF

Research Universities Leave Big Footprints

Labs Are Where the Action Is

Cornell total carbon inventory 319,000 tons CO2

Commuter travel

Air travelLab Buildings

All other buildings

9%

8%

37%

46%

Commissioning (Cx)

During design and construction

Ensures design intent is met

Uncovers equipment problems

Exposes design errors

Retro-Commissioning

Tune up existing buildings

Question design criteria

New generation controls andcomponents

Continuous Commissioning

Periodic diagnostics based on controldata

Low Flow Fume Hoods

Flow = Face area X Velocity

Reduceopeningthrough stopsor slidingpanels

Reducedvelocity in fullopen position

Improved aerodynamics toimproved containment atlower velocity for all sashpositions

Demand Controlled Ventilation

Demand Controlled Ventilation

Potential•Vary ventilation rate based on air quality•Reduce ventilation rate until there is a spill•Report on poor lab practices

Concerns•Inconsistent detection of various chemicals•Detection in return air sees diluted concentration•Sampling time may be too long

Chilled Beams

• Separate cooling from ventilation• Good office application• May have benefit for labs with high cooling load/ low ventilation

Reheat Systems

Simultaneous heating and cooling can problematic Variations of internal loads can be enormous.

A single zone requiring cooling can create artificialheating and cooling loads throughout the building.

Possible solutions: Raise supply air temperature as warm as possible to minimize reheating.

Put cooling coils or cooling fan coils in each zone.

Reheat systems maintenance issues: Water treatments to avoid valve failures.

Hot water pump system pressure control to avoid excess pressure thatcan cause erosion.

DDC controls to the zone to determine valve position.

Note: There is a Labs21 Best Practice Guide in Minimizing Reheat

What is the Minimum, Safe Ventilation Rate?

Standard

ANSI/AIHA Z9.5

NFPA-45-2004

ACGIH Ind. Vent 24th ed. 2001

ASHRAE Lab guide 2001

OSHA 29 CFR Part 11910.1450

ACH number

The specific room ventilation rate shall beestablished or agreed upon by the owner orhis/her designee.

Minimum 4 ACH unoccupied, occupied “typicallygreater then 8 ACH”

The required ventilation depends on thegeneration rate and toxicity of the contaminantnot on the size of the room in which it occurs.

4 –12

4 - 12

Current Topics in Laboratory Operation

Energy use and cost

Carbon footprint

Commissioning

Low flow hoods

Computational Fluid Dynamics (CFD)

Demand Controlled Ventilation

Chilled beams

Ventilation rate and control

Lab chemical classifications

Shared facilities

Maintenance cost reduction

Industry Resources

• Labs 21• Training Seminars on O&M, High Performance Lab Design

• Design Guide for Energy Efficient Laboratories

• Best Practices

• Annual Conference

• LEED for Existing Buildings• Requirement for

Comprehensive operational plan for all building systems

Commissioning plan, implementation and documentation

Repair or upgrade all components not working as they should

Re-test components

• ASHRAE Laboratory Design Handbook (2001)• O&M checklists for hoods, BSCs and HVAC systems

• Tabulates requirements of OSHA, ANSI and NFPA

Thank you for your attention