Ventilation Controls and Life

Safety Interface

NEHES Spring Seminar, March 20, 2015 Eugene A. Cable, P.E. , M.S.F.P.E.

Life Safety Consultants

NEHES Honorary Member

(518) 794-7237

Eugene.Cable@Fairpoint.Net

Randy Hussey, CHFM, CFPS

Fire Protection Officer

Eastern Maine Medical Center

Bangor, Maine 04402

rhussey@emhs.org

(207) 973-7037)

Objective

To understand the ramifications of fire

protection systems interface with HVAC

and ventilation rates

Provide ideas / options you can implement

to enhance systems interface and

minimize negative impact on infection

control

Background

Our fire protection goal is to provide:

– Life Safety: a reasonably safe environment for occupants; “to protect the [life of ] occupants not intimate with the initial fire development for the time needed to evacuate, relocate, or defend in place”

– A reasonable level of building functionality and continuity of operations, including infection control

Fire Protection Trumps:

ADA

Power doors must disconnect operations

Elevators stop operating

Water fountains cannot protrude into the 8 feet

Infection Control

Smoke control replaces infection control

HVAC shuts down – pressure relationships ruined

Definitions

Alarm: A warning of danger

False Alarm: an alarm received when there is no

danger or real hazard

Smoke: products of combustion, S, L, G

Dangerous Smoke: high levels of CO/ other G

Smoke Control System: produces pressure

differences to manage smoke movement

Smoke exhaust system: Fan units at 100 %

exhaust, no make-up air supply

What is Smoke?

“I smelled and saw smoke so moved the

patients and babies to the lounge area.”

“The corridor was full of smoke”

(Could see all the way down corridor 120 feet)

Smoke obscuration:

2.2% obs per ft = 120 feet visibility

3.6 % obs per ft = 65 ft visibility

Smoke becomes dangerous:

When fire grows larger than air can fully

combust:

– Guess at 3 feet high flame

- Fire enveloped by smoke layer

When chemical reaction for specific items

give off specific toxic products

– Plastic material vs. organic

“Smoke” Production Rates

Production depends on size of the fire

And height of clear space above the fire

“Smoke” Production Rates

Production depends on size of the fire

And height of clear space above the fire

3 ft diam fire/ 8 ft height above = 1257 cfm

3 ft diam fire/ 5 ft height above = 870 cfm

Smoke Flow Rates

from Full Room Involvement

Around room door cracks: 370 CFM

Door open 12 inches: 4,100 CFM

41.5 inch door wide open: 17,000 CFM

44 inch open door way: 20,000 CFM \

8 ft corridor/ 8 ft high/ 120 ft long = 7680 CF

Fire Room Pressure Differentials

Room heat 750 F = .04 inches H20

to corridor

Room full involvement 1500 F = .064

Smoke travel

Room flaming fire, smoke venting to

corridor, smoke travels 8 – 10 feet per

second (FM hotel corridor tests). (SFPE

Handbook)

Unattended patient bunches up linen on patient bed and slips hand under the pile

2 min 50 sec - Staff begin investigating odor of smoke

3 min 15 sec – Staff open door look and close door

4 min 0 sec – Quick Response Sprinkler Activated

4 min 13 sec – Lobby Pull Station Activated - ALARM

4 min 13 sec – Staff Member places call to FD 9-911

4 min 14 sec – Verified Smoke Detector Activated (58 sec delay)

4 min 24 sec – Second Pull Station Activated- corridor

4 min 30 sec – Water flow activation

10 min 2 sec - First firefighter at door to suite ( 6 min response)

Video

Pause for questions

To Randy Hussey

Smoke Control in HVAC Systems

NFPA 90A – Standard for the installation of air

conditioning and ventilation systems 1999 and

2012 editions

NFPA 90B – Standard for the installation of

warm air heating and air conditioning 1999 and

2012 editions

NFPA 91 Exhaust system for air conveying of

vapors, gases, mists and noncombustible

particulate solids 1999 and 2004 editions

Definitions

Combination Fire and Smoke Damper: A device that meets both fire damper and smoke damper requirements

Fire Damper: A device installed in an air distribution system and designed to close automatically upon detection of heat, to interrupt migratory airflow and to restrict the passage of flame.

Smoke Damper: A device within an air-

distribution system to control the movement of smoke.

Definitions NFPA 90A

2012 Edition

4.3.10.2: Smoke dampers shall be installed

in systems with a capacity greater than

15,000 ft3/min to isolate the air-handling

equipment, including filters, from the

remainder of the system on both the

building supply side and the return side, in

order to restrict the circulation of smoke,

unless specifically exempted by 4.3.10.2.1

or 4.3.10.2.2

Shafts NFPA 90A – 2012 Edition

5.3.4.2 : The shaft enclosure shall have a

minimum fire resistance rating of 1 hour

where such air ducts are located in a

building less than four stories high.

5.3.4.3 : The shaft enclosure shall have a

minimum of 2 hours where such air ducts

are located in a building four stories or

more in height.

Shafts and Ducts Cont’ NFPA

90A – 2012 Edition 5.3.4.5: Shafts that constitute air ducts or that enclose air ducts

used for the movement of environmental air shall not enclose the following:

1. Exhaust ducts used for the removal of smoke-grease-laden vapors from cooking equipment

2. Ducts used for removal of flammable vapors

3. Ducts used for moving, conveying, or transporting stock, vapor or dust.

4. Ducts used for the removal of nonflammable, corrosive fumes and vapors

5. Refuse or linen chutes

6. Piping except for noncombustible piping conveying water or other nonhazardous or nontoxic materials

7. Combustible Storage

Smoke Barriers NFPA 90A, 2012

5.3.5.1: Smoke dampers shall be installed at or adjacent to the point where air ducts pass through required smoke barriers, but in no case shall a smoke damper be installed more than 2 feet from the barrier or after the first air duct inlet or outlet, whichever is closer to the smoke barrier, unles otherwise permitted by 5.3.5.1.1 through 5.3.5.1.5

5.4.3: Smoke Dampers used for the protection of openings in smoke barriers or in engineered smoke control systems shall be classified in accordance with ANSI/UL 555S (Standard for safety smoke dampers)

Smoke Barriers NFPA 90A, 2012

Section 5.3.5.1.5; smoke dampers shall not be

required in occupacnies exempted by NFPA 101

Life Saefty Code or NFPA 5000 Building

Construction and Safety Code.

NFPA 101, 2000, 19.3.7.3 exception # 2; dampers

shall not be required in duct penetrations of smoke

barriers in fully ducted HVAC where an approved supervised sprinkler system . . .

Fusible Links NFPA 90A 2012

Edition

5.4.5.2.1 : Fusible Links shall have a

temperature rating approximately 50 deg f

above the maximum temperature that

normally is encountered when the system is

in operation or shut down.

5.4.5.2.2 : Fusible links shall have a

temperature rating not less than 160 deg. F.

Operating Room opened in December 2014

using NFPA 99- 5-4.1.2 and 3, 1999 edition

Note: NFPA 99- 2012 edition removed the

automatic smoke vent due to sprinkler

requirements and less severe fire risk

(flammable anesthetics no longer used)

HVAC designed to automatically exhaust

upon duct smoke detection.

HVAC designed to shut down upon

duct smoke detection at the unit.

HVAC is designed to supply air to

several areas including the operating

room.

Windowless OR’s

Does your OR have a dedicated

exhaust system that vents smoke?

Do the controls shut down the

surgical suite air-handling units?

Would the air handler affect

multiple OR’s

What is the impact on Infection

Control?