Ventilation Controls and Life Safety Interface - NEHES · Ventilation Controls and Life Safety...
Transcript of Ventilation Controls and Life Safety Interface - NEHES · Ventilation Controls and Life Safety...
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
Randy Hussey, CHFM, CFPS
Fire Protection Officer
Eastern Maine Medical Center
Bangor, Maine 04402
(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?