NBS

PubliAlllDb EbDT^l cations

NBSIR 84-2876

The Need and Availability of Test

Methods for Measuring the Smoke

Leakage Characteristics of Door

Assemblies

U S. DEPARTMENT OF COMMERCE

National Bureau of Standards

National Engineering Laboratory

Center for Fire Research

Washington, DC 20234

May 1 984

U S. DEPARTMENT OF COMMERCE

QC

100

. U56

34-2375

1934

NATIONAL BUREAU OF STANDARDS

NBSIR 84-2876

THE NEED AND AVAILABILITY OF TEST

METHODS FOR MEASURING THE SMOKE

LEAKAGE CHARACTERISTICS OF DOOR

ASSEMBLIES

national e OF S'';-. ID LI3HAR- f? . J QC

I /

I L/ Ls

, U ^

^ 4

~

Leonard Y. Cooper

U S. DEPARTMENT OF COMMERCE

National Bureau of Standards

National Engineering Laboratory

Center for Fire Research

Washington, DC 20234

May 1984

U.S. DEPARTMENT OF COMMERCE. Malcolm Baldrige. Secretary

NATIONAL BUREAU OF STANDARDS. EmMt Ambtar. Director

TABLE OF CONTENTS

Page

LIST OF FIGURES iv

Abstract 1

1. INTRODUCTION AND OBJECTIVE OF THIS WORK I

2. SMOKE COMPARTMENTATION 2

2.1 Clarification of the Term "Compartment" 2 2.2 Test Methods for Implementing Fire Compartmentation 3 2.3 Mechanisms of Intracompartraent Smoke Migration - Two Types of Smoke Compartments 4

2.4 A Key to Successful Smoke Compartmentation 5

3. THE IMPORTANCE OF CROSS-DOOR PRESSURE DIFFERENTIAL IN ESTABLISHING

A RATING FOR A FIRE COMPARTMENT DOOR ASSEMBLY 6

3.1 Pressure Differential and the Smoke Leakage of Fire

Compartment Door Assemblies 6

3.2 Pressure Differentials and the Fire Stopping Characteristics

of Door Assemblies

3.3 Some Naturally Occurring Pressure Differentials During

High-Rise Building Fire Scenarios 8

4. DOOR ASSEMBLIES, COMPARTMENTS OF SAFE REFUGE, AND LIFE SAFETY .... 9

4.1 General Considerations 9

4.2 The Pressurized Stairwell — An Example of a Compartment

of Safe Refuge 10

5. GENERAL PREDICTION AND CONTROL OF THE DEVELOPMENT OF THREATENING

CONDITIONS THROUGHOUT A FACILITY 1

6. REQUIRED NEW AND/OR REVISED DOOR ASSEMBLY TEST METHODS 12

6.1 Required Measurements 12

6.2 Leakage Under Ambient Conditions 14

6.3 Testing for Fire Endurance 14

6.4 Leakage Under Fully Developed Fire Conditions 15

6.5 Combined Tests 16

6.6 Leakage Under Medium Temperature Conditions 17

7. SUMMARY AND CONCLUDING REMARKS 17

8. ACKNOWLEDGMENTS 18

9. REFERENCES 19

-iii-
LIST OF FIGURES

Page

Figure l. Mechanisms of intracompartment smoke migration

(from reference ll) 22

Figure 2. A test concept for measuring leakage of door assemblies.

During course of test, valve opening is varied to

maintain AP , at the desired value (from

reference 2?^"? 23

Figure 3. Example of an air leakage test chamber that might be

used to carry out ISO DIS 5925/1 (from reference 28) 24

Figure 4. General arrangement of the air leakage apparatus to be

used to carry out ASTM E 283-73 (from reference 27) ....... 25

Figure 5. The test equipment arrangement for measuring leakage by

the proposed ISO DP 5925, Part 3 test method (redrawn from

reference 33) 26

Figure 6. Test equipment arrangement for a proposed high

temperature leakage test (from reference 42) 27

Figure 7. The test equipment arrangement for measuring leakage by

the CO

2

, tracer gas method (from reference 44) 28

Figure 8. Example of an air leakage test chamber designed to test

door assemblies at ambient and at medium air temperature

(from reference 37) 29

-iv-
THE NEED AND AVAILABILITY OF TEST METHODS FOR MEASURING

THE SMOKE LEAKAGE CHARACTERISTICS OF DOOR ASSEMBLIES

Leonard Y. Cooper

Abstract

This paper identifies and places into perspective

relevant information that would assist in focusing future

research and development on test methods to measure the

smoke leakage characteristics of door assemblies. The

concept of smoke compartmentation is introduced and

developed. The importance of cross-door pressure differential in establishing the performance of door assemblies

in fire generated environments is discussed. Door

assembly performance is then related to life safety, in

general, and to the design of compartments of safe

refuge, in particular. All of the discussion suggests a listing of required door assembly test methods, and,

finally, leads to a review of the availability and development status of existing and potential future test

method candidates.

Key words: compartmentation, compartment fires,

door assemblies, high-rise buildings, leakage, life

safety, pressure differential, pressurization, property

protection, safe refuge, smoke control, smoke movement,

stack effect, test methods.

1. INTRODUCTION AND OBJECTIVE OF THIS WORK

The fire stopping characteristics of door assemblies during certain

practical fire scenarios can be estimated with some confidence by means of

well-established test procedures. In contrast to this, the development of

analogous test procedures for estimating a door assembly's smoke stoppl ng

- 1 -
characteristics are only now being fostered by appropriate institutions such

as American Society for Testing and Materials (ASTM) , International Organization for Standardization (ISO) , and the National Fire Protection Association

(NFPA). Yet, it is well recognized that in real fire scenarios, contact with

environments contaminated with a fire's gaseous and solid products of combustion (i.e., smoke), even though they are far from the fire's combustion zone

(i.e., its flames), can pose as serious a threat to life and property as can with the fire itself [1-3]. It is the purpose of this paper to assemble and

place into perspective relevant information that would assist in addressing

facility design problems related to the latter situation.

The discussion to follow will focus attention on the relation between

smoke leakage of door assemblies and smoke spread throughout a facility.

However, smoke spread is a function of the leakage of all construction

elements of a facility's partitions - leakage, for example, through joints,

construction cracks, and penetrations around pipes, conduits and ducts, all of

which are commonplace in f loor/ceiling and wall assemblies. The relevance of

the basic discussion to smoke leakage of generalized facility partions should,

therefore, be emphasized here at the outset.

2 . SMOKE COMPARTMENTATION

2.1 Clarification of the Term "Compartment”

To fix ideas it is useful to clarify the terms "fire compartment "and

"smoke compartment", which will be used frequently in the discussion to

follow. Here, a fire compartment is meant to denote a single facility space,

or group of contiguous spaces (on the same, or even on different levels of the

facility) which is/are bounded by a partition envelope assembly engineered and

constructed to have significant, known, fire stopping characteristics. For a fire compartment of more than one facility space, the design fire-stopping

performance of the compartment should be assured regardless of which compartment space(s) contain the fire.

A smoke compartment is analagous to a fire compartment. Its envelope is

designed and constructed to have known smoke-stopping or smoke-leakage rather

-2 -
than fire-stopping characteristics. A smoke compartment of fire involvement

is the smoke compartment which actually contains the fire. The smoke-stopping

performance of a smoke compartment partition element would be assured independent of the location of the fire within the compartment.

By design, it is possible that a smoke or fire compartment of fire

involvement will reliably maintain its integrity for only a specific, limited

time interval into the fire. After this time interval, failure in a relatively weak component of the compartment envelope, say, onset of significant

warpage of a compartment door or failure of seals due to high temperature

exposure, could lead to a new, enlarged, smoke or fire compartment of fire

involvement. Whereas the original compartment may have involved a relatively

small portion of the facility, the new compartment could be much larger,

possibly even encompassing all parts of the facility except for smoke compartments of safe refuge.

While it is possible for a smoke compartment and a fire compartment to be

identical, this need not be the case. For example, a fire rated compartment

envelope may be designed to provide reliable fire stopping during the course

of likely hazardous fires for a one hour period. Yet, if the smoke leakage

characteristics for all or part of the envelope, e.g. , of the door assemblies,

are unknown, and if the facility is not equipped with an appropriate system

for pressurization, then it may be necessary to consider a much larger portion

of the facility as the smoke compartment of fire involvement.

2.2 Test Methods for Implementing Fire Compartmentation

In the design of facilities, fire compartmentation has been classically

used to impede the spread of fires from one space to another. In this regard,

several test methods [4-10] have been developed to measure the time that a particular construction element will reach agreed-upon criteria of failure

when exposed to a standard, fully developed fire. Thus, by proper choice of

rated construction elements, which include door assemblies, one can, under

certain limited circumstances, anticipate containment of a fire to the

compartment of fire origin for a time interval of, for example, one, two, or more hours. The limited circumstances referred to include those where wind

-3 -
loading, stack effect and/or facility ventilation would not lead to significant positive pressures (relative to adjacent compartments) in fire compartments of fire involvement.

While compartment constructions might predictably contain the spread of

fire to adjacent spaces, they may or may not necessarily abate the spread of

smoke to any significant degree. Yet, most would probably agree that with

care in design, construction, and installation, significant reduction in

typical smoke leakage from a smoke compartment of fire involvement to an adjacent compartment can indeed be achieved. If compartment envelopes could

be so implemented, and, just as important, if meaningful characterizations of

the smoke leakage performance of such envelopes during real fire scenarios

could be established, then, as in the case of fire compartmentation , smoke

compartmentation would be an important concept. Smoke compartmentation would

be convenient and useful for understanding, developing and implementing

methods of controlling smoke spread.

2.3 Mechanisms of Intracompartment Smoke Migration - Two Types of Smoke Compartments

It is useful to identify characteristics of the two basic types of smoke

migration mechanisms which are depicted in Figure 1. One of these would be

associated with the smoke compartment of fire involvement, and the other with

all other smoke compartments of a facility.

Because of relatively high smoke temperatures and associated large

temperature differences, the buoyancy forces which lead to strong intracompartment stratification will dominate the dynamics of smoke migration within

one or all spaces of a smoke compartment of fire involvement. However, once

smoke has been transported from this compartment through penetrations (e.g.,

leaks in a doorway assembly) in its boundaries, and into an adjacent smoke

compartment, different primary mechanisms of further smoke migration can come

into play. If the rate of smoke leakage into adjacent compartments is limited

-4-
by well-designed partition assemblies, then it is reasonable to expect success in a model of further smoke spread which assumes that entering smoke

is continuously and uniformly mixed throughout adjacent compartment environments. Such mixing would be driven, for example, by forced ventilationgenerated air currents, and by buoyancy-driven wall flows [12,13]. This

suggests a second, "tracer-gas migration" type of mechanism or the smoke's

continued transport throughout the facility. The term "tracer-gas migration"

is meant to indicate a mechanism of intrafacility smoke movement, outside the

smoke compartment of fire involvement, which is characterized by timedependent, compartment-to-compartment, migration and dilution of relatively

cool smoke. The intrafacility smoke migration and dilution is driven by

pressure differences between uniform environment compartments, which are generated by forced ventilation systems, wind effects, stack effects, or a combination of these driving forces.

2.4 A Key to Successful Smoke Compartmentation

If one accepts the above description, successful smoke compartmentation

can be achieved if, by design, there is a switchover from strong and rapid

smoke spread, due to significant and unavoidable stratification on the fire

side of a smoke compartment barrier, to a conceptually simpler and more easily

analyzed tracer-gas migration smoke spread, on the other side of the barrier.

The designed switchover to the tracer-gas migration mechanism of smoke

spread outside the smoke compartment of fire origin is key in that it would

allow an achievable and practical method of analysis of total lntrafacillty

hazard development. The method of analysis referred to would involve an

There is an important exception to this expectation. This has to do with

the movement and mixing of smoke in tall, narrow spaces such as shafts,

stairwells and tall, narrow atriums. The dynamics of smoke Introduced into

such spaces, even if at a temperature only moderately above the local

ambient will tend to bear strong similarities with the aforementioned smoke

dynamics of the fire compartment. Thus, for better or for worse, strong

stratification of the smoke may develop, and an analysis or design based on the assumption of a uniform, fully mixed environment throughout the shaft,

stairwell or atrium can lead to significant error. Modeling of the dynamicenvironment within such high aspect ratio spaces (l.e., large ratio of

height to compartment width) is an important and relevant problem whose

solution is only now in the research stage^.

-5-
enclosure fire model of appropriate detail (e.g., like one of those of references 14-18) for predicting events in the smoke compartment of fire involvement, and a facility infiltration and ventilation model (e.g., like one of

those of references 19-21) for all other smoke compartments of a facility.

To specify or evaluate fire safety, requirements of safe available egress time

[22] would be established for the different types of smoke compartments of the

facility. Criteria for a safe compartment environment would be established,

where these would be based on predictable fire environment descriptors (e.g.,

the level of smoke dilution relative to concentrations in the smoke compartment of fire fire Involvement).

In the above type of facility fire safety evaluation, it would not necessarily be the role of the fire test community to establish requirements of

safe available egress time and criteria for a safe environment (a task

partially attempted, for example, in reference 23). However, this community

would clearly have a role In the development of door assembly, smoke leakage,

test methods. Indeed, the ability to carry out the Indicated type of analysis

of hazard development at any level of sophistication Is totally dependent on a quantitative description of the leakage characteristics of door assemblies.

3. THE IMPORTANCE OF CROSS-DOOR PRESSURE DIFFERENTIAL IN ESTABLISHING

A RATING FOR A FIRE COMPARTMENT DOOR ASSEMBLY

3.1 Pressure Differential and the Smoke Leakage of Fire

Compartment Door Assemblies

The last section discussed mechanisms for smoke migration both inside and

outside the compartment of fire Involvement. As depicted in Figure l, the

physical and operational link between these two spaces, the fire compartment

and the rest of the facility, are the actual compartment boundary components,

e.g., connecting door assemblies, and their leakage characteristics. In the

context of a compartment containing a fire, we specifically refer to the

leakage of smoke across door assemblies which are potentially exposed on one side to developing and fully developed fire environments, and where the smoke

is driven by a cross-door pressure differential.

-6 -
The existence of a cross-door pressure differential is key to the evaluation of a door assembly design! In particular, a variety of possible pressure

differential magnitudes and directions (higher or lower pressure in the

compartment relative to the adjacent space) can occur in practice. For

example, stack effect alone can lead to (relatively) uniform, positive or negative, cross-door pressure differentials of the order of several tens of

pascals or higher when compartments of fire involvement are exposed to the

outside environment through broken windows [24]. Steady wind velocities of,

say, 25 mph would add or subtract up to 75 Pa [25,26], and this value is

proportional to the square of the wind velocity. Over and above these uniform

pressures, fire-generated cross-door pressure differentials can vary from top

to bottom of a doorway on the order of ± 5-10 Pa [24]. Depending on which

pressure conditions can be anticipated for a particular compartment in a given

facility, totally different quantities of smoke could be transferred across

door assemblies of identical design.

3.2 Pressure Differentials and the Fire Stopping Characteristics

of Door Assemblies

Not enough attention has been paid in the past to the potential Impact of

cross-door pressure differentials on the actual fire stopping capabilities of

door assemblies. Thus, with unknown consequences, a fire door assembly may be

subjected to the above-mentioned type of fire scenario involving positive,

cross-door, pressure differentials of several tens of pascals. For example, a door assembly may receive a one hour fire endurance rating in an ASTM E152 [6] or ISO 3008 [8] test, where the test conditions involved a relatively modest,

cross-door, pressure differential condition of, say, ±10 Pa. But, when

similarly tested under a pressure condition which simulated a realistic, highoverpressure fire scenario, it is possible that the same door assembly would

receive a significantly reduced fire endurance rating. Alternatively,

consider a facility which includes an automatic smoke control system which is

designed to maintain a negative pressure (relative to all adjacent compartments) in any potential compartment of fire origin. Then, depending on the

magnitude of the designed cross-door pressure differential, it Is reasonable

to speculate that a desired one hour of protection against the spread of f 1 r<* may be achievable with a door assembly having an ASTM E152 or ISO 3008 railin'.

-7 -
(obtained, say, under modest positive over-pressure conditions) significantly

less than one hour. Safety and cost tradeoffs implicit in the above examples

are obvious.

The point of the above discussion is that there may be good reason to

rate and take account of the fire-stopping capability of door assemblies

relative to, and as a function of cross-door pressure differential. To obtain

such ratings a revised ASTM E152 or ISO 3008 with a significant furnace

pressure control capability and/or with other means of achieving a cross-door

pressure differential control capability (e.g., by the method proposed in

reference 24) would be required.

3.3 Some Naturally Occurring Pressure Differentials During

High-Rise Building Fire Scenarios

In order to place the cross-door pressure differential question into

perspective, and as a case in point, it is Instructive to consider the use of

door assemblies in high-rise buildings or, more directly, in buildings where

stack effects are significant. (Even in low facilities, steady winds could

lead to the type of pressure loadings to be discussed here.) Assume, for

example, that cross-exterior-wall pressure differences during normal winter

days in a building of interest are of the order of several tens of pascals at

the lower floors (higher pressure outdoors) and at the upper floors (higher

pressure indoors). Now consider the following scenario:

Fire breaks out in a compartment on a low floor of the building during

the winter. The compartment flashes over, and a ventilation controlled fire

develops, where ventilation is from broken windows on exterior walls. Once

the windows break, the pressure in the fire compartment is substantially

maintained at the (relatively high) outdoor pressure. The fire compartment is

connected to adjacent compartments by partitions with relatively small penetrations, e.g., (closed) door assemblies. The pressure in these adjacent

compartments is substantially maintained at a (relatively low) indoor pressure

which is characteristic of the low floor under consideration. The pressure

drop across the partitions is therefore maintained at levels which are of the

order of magnitude of several tens of pascals, l.e., at levels which are of

-8-
the order of magnitude of indoor-to-outdoor , stack-effect-generated pressure

differentials.

Note that in the above scenario it is reasonable to anticipate rates of

smoke leakage across fire compartment door assemblies which could be significant. (This would depend, of course, on the actual in situ leakage characteristics of the door assemblies involved.) It is also noteworthy that if the

fire compartment was on a high floor, it would be maintained at a smaller

pressure than adjacent compartments, and smoke leakage to the rest of the

building would be substantially eliminated.

4. DOOR ASSEMBLIES, COMPARTMENTS OF SAFE REFUGE, AND LIFE SAFETY

4.1 General Considerations

Outside of a fire compartment, and by virtue of the existence of closed

door assemblies and other barriers to fire and smoke spread, every compartment

of a facility through which occupant egress could occur will be maintained at

safe conditions at least for some limited time into the fire. However, in

order to achieve facility designs which are compatible with life safety, it is

desirable to designate and design certain specific spaces as compartments of

safe refuge. The environment in such compartments would be maintained under

tenable conditions for significant (although, not necessarily indefinite),

specified time intervals.

Three types of information are required to design compartments of safe

refuge with confidence. First is some knowledge of the leakage characteristics of candidate door assemblies. Second are estimates of the likely smoke

conditions which will occur in those smoke compartments adjacent to a smoke

compartment of safe refuge. As suggested by the discussion in the previous

section, a third and final type of input is the anticipated level of pressure

differential between potential smoke-laden adjacent smoke compartments and the

protected compartment itself.

Pressurized stairwells are examples of smoke compartments of safe refuge.

A discussion of these kinds of compartments will now be presented to Illus-

-9 -
trate the type of inputs required for their successful design. This discussion is presented here mainly for the purpose of highlighting the general

types of door assembly leakage measurements that a facility designer might

require. For specific design information about pressurized stairwells and

other smoke control systems the reader is referred to reference 26.

4.2 The Pressurized Stairwell — An Example of a Compartment of Safe Refuge

It would clearly enhance the safety of a facility if stairwells were designed as smoke compartments of safe refuge for time intervals required to

evacuate all occupants to other, more secure compartments or to the outside.

Toward this end, the pressurized stairwell design concept has been developed

[1,3]. By introducing fresh air into a stairwell with the use of appropriate

blower hardware and control, it is possible to maintain the stairwell at a practical positive pressure relative to all adjacent compartments during many

realistic fire scenarios and related stairwell door usage. Provided the

stairwell door to the floor of fire Involvement is closed, such stairwell

designs would lead to a positive flow of fresh air across door assemblies from

the stairwell compartment to all adjacent spaces (including those on the fire

floor). Thus, the fully successful pressurized stairwell will "never" allow

leakage of smoke (or air) into the stairwell compartment from adjacent

building spaces. In particular, all smoke infiltration into the stairwell Is

eliminated so long as the doors and other partition construction elements of

the stairwell maintain their Integrity.

The design of the stairwell pressurization system clearly requires

knowledge of the leakage characteristics of entry/exit door assemblies.

Except for the fire floor, we are talking here about leakage of unheated air across a(n unheated) door assembly under design conditions of cross-door

pressure difference. Leakage characteristics of this type could be acquired

with ASTM E 283, [27] or with the proposed ISO 5925 Part l [28] test method.

For the fire floor (assuming no protected lobby on the other side of the door)

one also requires knowledge of the leakage characteristics of the door

assembly as it is exposed to fully developed fire conditions. Here we are talking about leakage rates that would be measured, for example, in a door

assembly fire endurance test (such as ASTM E152 or ISO 3008, appropriately

- 10-
revised to allow for leakage measurements) where the test laboratory furnace

was maintained at such a level of negative pressure, relative to the pressure

at the unexposed side of the door, as to simulate the stairwell-to-f ire

compartment pressure differential.

There is at least one class of realistic fire scenario, and stairwell

door usage where the latter pressurized stairwell design considerations may

not be adequate (unless the most up-to-date pressurization design technology

is used) [26]. Reference is made to the use of doors during high-rise

building evacuation at times of cold winter conditions. Under such circumstances, it may not be practical to maintain a positive pressure difference

between the stairwell and the outside at the elevation of the lower floors of

the building (see, for example, the building measurements reported in

Figure 10 of reference 29). Thus, with a fire in a lower floor which is

vented directly to the outside through broken windows (as in the fire scenario

referred to in an earlier section), the smoke compartment (floor) of fire

origin will be at a positive pressure relative to the stairwell. Under this

circumstance there will be unavoidable continuous smoke leakage Into the

stairwell. But it is clear that the stairwell pressurization system could

accept some limited smoke Intake without leading to any serious degradation in

the stairwell environment during the required time interval for safe refuge.

Therefore, one design task would be to choose a candidate door assembly whose

leakage characteristics were such that this established design limit would not

be exceeded. Such leakage characteristics could only be established by

carrying out a test (such as the one recommended in reference 24, depicted

here in Figure 2 and, as yet to be developed) which measured the leakage rate

of a door assembly while it was undergoing a fire endurance test exposure with

positive furnace-to-unexposed-side pressure differential.

5. GENERAL PREDICTION AND CONTROL OF THE DEVELOPMENT OF THREATENING

CONDITIONS THROUGHOUT A FACILITY

Door assembly leakage characteristics are required to describe a facility's fire-generated environment, in general, and to design smoke

compartments of safe refuge, in particular. As suggested in earlier dismission, by implementing an appropriately conservative design concept like the
"perfectly" pressurized compartment of safe refuge, (i.e., no smoke entry

under design conditions), it is often possible to simplify the latter design

task, and to do this in a manner which requires only the most approximate door

leakage characteristics. Indeed, it is with the use of "perfect" pressurization that the safe egress path problem is now being solved [26]. However, if

facility designs are to be responsive to more flexible fire safety performance

criteria, it is evident that approaches for solving the inherently coupled

problems of compartment-to-compartment smoke spread are required. Such

approaches would be based on tools for predicting or mathematically simulating

the fire-generated smoke environments which develop throughout a facility

subsequent to the ignition of a potentially threatening fire. These would

include mathematical models for predicting fire growth phenomena in multiroom

spaces of a compartment of fire involvement, and the migration of smoke to all

other compartments of the facility (e.g., to compartments of designed safe

refuge), whether as a result of forced ventilation, stack effect, windgenerated pressure differences, smoke buoyancy, or a combination of these.

Key to overcoming the challenges in developing fire environment simulation models are the compromises which must be made between accuracy and detail

in simulation of physical phenomena, on the one hand and practicality of

implementation on the other (i.e., to be successful, the analytic tools to be

developed will have to be both reliable and "user friendly"). Once developed,

dynamic fire environment prediction models will be used together with models

which predict the response of people and property to such environments. It

will then be possible to systematically establish the life or property safety

performance of a facility on a fully integrated, economical and rational basis

[U].

6. REQUIRED NEW AND/OR REVISED DOOR ASSEMBLY TEST METHODS

6.1 Required Measurements

Based on all of the previous discussion it follows that test methods are required to evaluate the following performance characteristics of door

assemblies used in the partitions of smoke compartments:

- 12-
1. Rate of leakage under ambient temperature conditions, as a function of cross-door pressure differential.

2. Fire endurance time (according to criteria similar to those set

forth in ASTM E152) of an interior door assembly under conditions where one side is exposed to a fully developed (flashedover) fire simulation, the other side is exposed to an ambient

environment, and where the assembly is subjected to a crossdoor pressure differential between, say, ± 100 pascals.

3. Rate of leakage as a function of time (up to the assembly's

fire endurance time, as established in measurement 2, above)

under conditions where one side is exposed to a fully developed

( f lashed-over) fire simulation, the other side is exposed to an ambient environment, and where the assembly is subjected to

cross-door pressure differential between, say, +100 pascals and

values that are (slightly) negative enough as to lead to zero leakage conditions.

It has been suggested [23,30] that another test method is required to

evaluate leakage characteristics under medium temperature ( 100°C-250°C)

exposure conditions. Such a test method would be used to estimate the leakage

characteristics of door assemblies which were not (yet) exposed to flashover

conditions, but which, by reason of proximity to a smoke compartment of fire

involvement, were exposed to significantly elevated temperature environments

(as might be eventually anticipated in an “Intermediate" compartment between

the fire compartment and a compartment of safe refuge).

A test method developed to acquire and report any of the above measurements on a particular door assembly would likely Include a shorthand means of

summarizing the test results. Such a summary would take the form of a rating

or classification system (as, e.g., suggested in reference 23) which could be

used as a convenient means of reference between facility design guLdes

,

standards, codes, etc.

- 13-
6.2 Leakage Under Ambient Conditions

The ambient leakage measurements under item l above could be acquired by

implementing ISO 5925, Part l (Figure 3), or ASTM E283 (Figure 4).

The measurements obtained by one of these test methods would provide door

assembly leakage characteristics required in the analysis of pressurized

stairwell designs, in the early time analysis of smoke leakage from fire

compartments to the rest of a facility, and, generally, in analyses of total

InLraf acillty smoke migration.

Besides actual laboratory evaluations of ambient temperature leakage, a method of carrying out insltu testing of door assemblies would also be of

interest. The results of such tests, on insltu elevator and stair shaft

doors, are reported, for example, in reference 31, and ASTM E783 [32] is an existing field test method for exterior doors.

For an Indepth discussion on measurements, calculations and specifications of door assembly leakage under ambient conditions the reader is referred

to reference 25.

6.3 Testing for Fire Endurance

As discussed in an earlier section, the fire endurance of a door assembly

may be very sensitive to the magnitude and direction of cross-door pressure

differentials. To obtain fire endurance ratings under practical, nonzero,

cross-door pressure differentials a significantly revised ASTM E152 or similar

type furnace driven test method would be required. The major aspect of the

revision would be in the operation of the furnace at pressures significantly

higher or lower (say, between ± 100 pascals) than the pressure on the

unexposed side of a subject door assembly. Short of actually operating the

furnace at such positive or negative pressures relative to the test laboratory

(i.e., relative to the ambient), one possible alternate means of achieving

such cross-door pressure differentials would be by use of a door enclosure box

(as in the tentative ISO 5925, Part 3 test method [33], depicted in Figure 5).

The door box would be attached to the wall in which the door assembly was

- 14-
mounted, and it would enclose the entire subject door assembly on its

unexposed side. By appropriate ventilation and surface cooling of the box, as recommended in reference 24 (Figure 2), the unexposed door surface would be

continuously subjected to a simulated ambient environment. Further, the box

would be operated at such a negative or positive pressure, relative to the

(ambient pressure) furnace, as to achieve the desired cross-door pressure

differential

6.4 Leakage Under Fully Developed Fire Conditions

During the last decade much attention has been focused on the development

of test methods to measure the leakage of door assemblies under fully developed fire exposures. The first of these test methods, which was limited to near zero cross-door pressure differentials, was developed in Finland [34-36]

in the early 1970's and proposed to a working group of ISO. The working group

documented the test method [33] with the anticipation that, if acceptable, it

would eventually be Issued by ISO as the third of a three part series of tests

for measuring the leakage of door assemblies under ambient temperature [27,36]

(DP5925, Part l), medium temperature [37] (DP5925, Part 2), and high temperature [33] (DP5925, Part 3). Also planned for this series is an Introductory

or commentary document [23,30] (DP5925, Part 0). An annotated sketch of the

high temperature, DP5925, Part 3 test method is presented in Figure 5.

An indepth experimental [37] and theoretical analysis of the DP5925,

Part 3 test method was carried out in the U.S. A report of this study [24]

indicated that, for a variety of reasons, the test method is generally

unreliable. The report went on to recommend an alternate test concept which

would hopefully remove the problems as well as the significant limitation of a near-zero, cross-door pressure differential. The proposed test concept, which

is depicted in Figure 2 (and has yet to be implemented), involves the use of a ventilated enclosure box referred to earlier.

Independent of the latter analysis, experimental studies on an improved

DP5925, Part 3 test method were carried out in the Netherlands [39-42]. The

hardware of this revised test method is illustrated in Figure 6. As can be

seen, it also makes use of a ventilated enclosure box. While this test metho i

- 15-
may finally prove Lo be reliable, it does not address the issue of elevated,

cross-door pressure differentials.

The above test methods all make use of structures which enclose the

subject door assembly and which collect and measure the total rate of leakage

of furnace gases. Another method for measuring the rate of leakage under

fully developed fire exposures, which does not involve the use of a cumbersome

enclosure box, is now under development in Finland [43,44]. This method,

depicted in Figure 7, makes use of carbon dioxide (CC^) as a tracer gas of

known (measured) concentration within the furnace. The tracer gas, uniformly

mixed with other furnace gases, leaks past the door assembly. On the

unexposed side of the door all leaked gases rise due to buoyancy, and they are collected in an open, ventilated canopy (reminiscent of the canopy smoke

collection used in reference 45). The rate of tracer gas flow is measured and

related to the total leakage rate of the door assembly.

Two criticisms of the latter test method have been raised and partially

refuted [44]. The first has to do with the strong variation of CC^* tracer

gas concentration within the furnace, and the second has to do with the fact

that unknown amounts of CO

2 may be introduced at burning surfaces near leakage

gaps of the door assembly, thereby leading to spurious estimates of total

leakage rate.

Short of pressurizing the furnace relative to the laboratory ambient, or using the ventilated enclosure box idea, it does not appear that the above,

tracer gas test method will provide leakage rates of door assemblies under

significant cross-door pressure differentials.

6.5 Combined Tests

Under significant cross-door pressure differentials it is likely that

successful methods to measure fire endurance and leakage under fully developed

fire exposures will require substantial research and development activity.

Furthermore, to implement such test methods and obtain ratings for a particular door assembly design will clearly require resource commitments which will

be even greater than those presently required under ASTM E152. (For example.

- 16-
to obtain a leakage classification under two different cross-door pressure

differentials would likely require destructive tests on each of two separate

door assemblies.) For this reason it would be a particularly attractive

feature of the test methods if both types of evaluations, fire endurance and

leakage, could be carried out during the course of a single test procedure.

Thus, for example, if the leakage test concept of reference 24 (Figure 2)

proved to be practical, then (except for the possible difficulty of carrying

out a hose stream test) there is no particular reason why fire endurance and

leakage rate could not be established simultaneously.

6.6 Leakage Under Medium Temperature Conditions

Leakage of door assemblies under both ambient and medium temperature (up

to 200°C) conditions, and with cross-door pressure differentials of up to

± 100 pascals have been successfully carried out in Germany with a single test

apparatus [37]. The apparatus, which is depicted in Figure 8, uses a 60 kW

electric heating device. The elevated temperature tests were initiated at

ambient conditions and required from 25 to 30 minutes to reach maximum

temperature

7. SUMMARY AND CONCLUDING REMARKS

Key to the protection of life and property during fires is the control of

smoke migration. Such control can be designed into a facility to the degree

that the structural integrity and leakage characteristics of compartment

partitions are known during real fire conditions. One parameter of real fire

conditions which will have a great impact on these characteristics is the

cross-partition pressure differential. In practical fire scenarios such

pressure differentials can be sustained by steady wind loadings, stack effect,

and/or ventilation systems at amplitudes which could easily be of the order of

several tens of pascals.

The measurement of the structural Integrity and leakage characteristics

of compartment partition elements require test methods which are at various

stages of development. Required measurement capabilities for door assemblies,

in particular, include leakage rate under ambient temperature conditions

- 17 -
(insitu as well as laboratory testing), fully developed fire conditions, and,

possibly, under intermediate temperature exposures, for fixed cross-door

pressure differentials within some range to be determined. Also required is a capability to evaluate door assembly fire endurance under a similar range of

fixed, cross-door pressure loadings. At a given pressure loading there is reason to expect that with a carefully designed test method the latter fire

endurance evaluation could be successfully carried out together with leakage

measurements during a single test procedure.

A method of reporting summary results of test evaluations, basically a rating or classification system, has to be developed. For example, summary

results presented in a shorthand form might Include: cross-door pressure

differential, test exposure (e.g., ambient or fully developed fire temperatures), and characteristic rates of leakage (in the case of elevated temperature exposure, e.g., maximum leakage during the first 30 minutes, second 30

minutes, etc., up to the fire endurance rating of the assembly). Such a rating or classification system would be used In performance or specification

guides, standards, and codes for selecting door assemblies to be used in

different applications within different types of facilities. In the future,

such use documents will have to be prepared by appropriate organizations.

Institutions such as ASTM, ISO, and NFPA clearly have a role to play in

establishing, improving, promulgating, and in encouraging the development of

the above test methods, reporting procedures, and use documents.

8 . ACKNOWLEDGMENTS

This work was supported in part by the U.S. Department of Health and

Human Services, and the Bureau of Mines and National Park Service of the U.S.

Department of Interior.

- 18-
9. REFERENCES

[1] Fire and Smoke Control, Chapter 41, 1973 ASHRAE System Handbook.

[2] Smith, F. , Defining the Role and Performance of Smoke Doors, Fire

Prevention, Vol. 148, 1982.

[3] Butcher, E. G. and Parnell, A. C. , Smoke Control and Fire Safety Design,

E and F. N. Spon Ltd., London, 1979.

[4] Uniform Building Code Standard No. 43-2: Fire Tests of Door Assemblies,

1982 Edition.

[5] ASTM E 119-83, Fire Tests of Building Construction and Materials,

Vol. 04.07, Annual Book of ASTM Standards, 1983.

[6] ASTM E 152-8la, Fire Tests of Door Assemblies, Vol. 04.07, Annual Book

of ASTM Standards, 1983.

[7] ASTM E 163-80, Fire Tests of Window Assemblies, Vol. 04.07, Annual Book

of ASTM Standards, 1983.

[8] ISO 3008, Fire Resistance Tests — Door and Shutter Assemblies, 1976.

[9] ASTM E 814-83, Fire Tests of Through-Penetration Fire Stops, Vol. 04.07,

Annual Book of ASTM Standards, 1983.

[10] NFPA 252 Standard Method of Fire Tests of Door Assemblies, NFPA National

Fire Codes, Volume 10, 1979.

[11] Cooper, L. Y. and Nelson, H. E., Life Safety Through Designed Safe

Egress — A Framework for Research, Development and Implementation,

Sixth Meeting of UJNR Panel on Fire Research and Safety, Tokyo, May 10-

14, 1982.

[12] Cooper, L. Y., On the Significance of a Wall Effect in Enclosures with

Growing Fires, to appear In Combustion Science and Technology.

[13] BRE News, Smoke Movement in Corridors, Building Research Establishment,

England, 60, 1983.

[14] Cooper, L. Y. , A Mathematical Model for Estimating Available Safe Egress

Time in Fires, Fire and Materials, 6, 3/4, p. 135 (1983).

[15] Emmons, H. W. , The Prediction of Fires In Buildings, 17th Symp. (Inter.)

on Combustion, p. 1101 (1979).

[16] Zukoski, E. E. and Kubota, T. , Two Layer Modeling of Smoke Movement In Building Fires, Fire and Materials, 4, l, p. 17 (1980).

[17] Tanaka, T. , A Model of Multiroom Fire Spread, NBSIR 83-2718, National

Bureau of Standards, Washington, DC (1983).

- 19 -
[18] Hagglund , B., Simulating the Smoke Filling in Single Enclosures,

FOA C 20513-D6, National Defense Research Inst., Stockholm, Sweden

(1983).

[19] Wakamatsu, T. , Calculation of Smoke Movement in Buildings, Japan

Ministry of Construction, Building Research Inst., Research Paper 34,

Tokyo, Japan (1968).

[20] Evers, E. and Waterhouse, A., A Computer Model for Analyzing Smoke

Movement in Buildings, Fire Research Station, CP69/78, Building Research

Establishment, Borehamwood, England (1978).

[21] Edwards, J. C. and Greuer, R. E., Real-Time Calculation of Product-ofCombustion Spread in Multilevel Mine, Information Circular 8901, U.S.

Bureau of Mines, Pittsburg, PA (1982).

[22] Cooper, L. Y., A Concept for Estimating Available Safe Egress Time in

Fires, Fire Safety Journal, 5, p. 135, 1983.

[23] A Guide to the Role and Use of Fire Doors in Buildings Related to ISO

Fire Tests, ISO/TC 92/WG 3 N 277, 1981.

[24] Cooper, L. Y., Measuring the Leakage of Door Assemblies During Standard

Fire Exposures, Fire and Materials, Vol. 5, No. 4, 1981; also,

NBSIR 80-2004, U.S. National Bureau of Standards, 1980.

[25] Gross, D. , A Review of Measurements, Calculations and Specifications of

Air Leakage Through Interior Door Assemblies, Building Standards,

Vol. I, No. 2, 1981; also NBSIR 81-2214, U.S. National Bureau of

Standards, 1981.

[26] Klote, J. H. and Fotherglll, J. W. , Design of Smoke Control Systems,

NBS Handbook 141, National Bureau of Standards, 1983.

[27] ASTM E 283-73, Standard Test Method for Rate of Air Leakage Through

Exterior Windows, Curtain Walls, and Doors, Part 18, Annual Book of ASTM

Standards, 1980.

[28] ISO DIS 5925/1, Fire Tests — Evaluation of Performance of Smoke Control

Door Assemblies — Part 1: Ambient Temperature Test, 1981.

[29] Tamura, G. T., Experimental Studies on Pressurized Escape Routes, Trans.

ASHRAE, Vol. 80, Part 2, 1974.

[30] DP 5925 Fire Tests — Smoke Control Door and Shutter Assemblies,

Part 0 -- Commentary, ISO/TC 92/WG 3 N 204, 1977.

[31] Tamura, G. T. and Shaw, C. Y. , Air Leakage Data for the Design of

Elevator and Stair Shaft Pressurization Systems, ASHRAE Transactions,

Vol. 81, 1975.

[32] ASTM E 783-81, Field Measurement of Air Leakage Through Installed

Exterior Windows and Doors, Part 18, Annual Book of ASTM Standards,

1981.

- 20-
[33] DP 3925 Fire Tests — Smoke Control Door and Shutter Assemblies,

Part 3 - High Temperature Test, ISO/TC 92/WG 3 N 189, 1977.

[34] Oksanen, P., ISO/TC 92/WG 3 N 102.

[35] Oksanen, P., Results of Air Leakage and Fire Tests on Doors, ISO/TC

92/WG 3 N 106, 1973.

[36] Oksanen, P., Some Details of the Fire Test Method for Smoke Control

Doors, ISO/TC 92/WG 3 N 143, 1975.

[37] Westhoff, W. , Ueberall, T., Results of Tests for Performance of Smoke

Control Door Assemblies at Ambient and Medium Temperatures, ISO/TC 92/WG

3 N 276, 1981.

[38] Berhinig, R. M. , Measurement of Air Flow Around Doors Under Standardized

Fire Test Conditions, NBS-GCR-8 1-330, National Bureau of Standards

(prepared by Underwriters Laboratories Inc. under Grant G8-9010), 1981.

[39] Dekker, J., Proposals to Improve the Oksanen Box and DP 5925 Part 3,

ISO/TC 92/WG 3 N 197, 1978.

[40] Dekker, J. and Haffmans, L., Comments on ISO DP 5925 Parts 2 and 3

received from TNO, ISO/TC 92/WG 3 N 209, 1978.

[41] Dekker, J., Smoke Control Door High Temperature Test, ISO/TC 92/WG 3 N

221 .

[42] Dekker, J. and Haffmans, L. , Report Concerning DP 5925 Part 3: High

Temperature Test, ISO/TC 92/WG 3 N 265, 1981.

[43] Ahonen, A., A New Method for Measuring the Fire Gas Leakage of a Structural Part Under Standard Fire Conditions, ISO/TC 92/WG 3 N 267,

1981.

[44] Loikkanen, P., Use of Tracer Gas to Evaluate the Fire Gas Leakage of

Doors, ISO/TC 92/WG 3 N 278, 1981.

[45] Shoub, H. and Gross, D. , Doors as Barriers to Fire and Smoke, National

Bureau of Standards Building Science Series 3, 1966.

- 21 -
Need

leakage

characteristics

of

partition

assemblies

during

fire

exposure

-r~y £o

to0)

DC

CO

o>c

co j2 Ui

<2 - o U c oE#® "D 3 O -N TM

32

® § * HU

|j .1 S « c u ^ ^ 0) 1 S-E^S

-O

MC 0) <D <l> o fc X > P

OEo op 3

-Q2 o C O — (o

"5 *

ii 0) E

CO ^ E .E o o> o a c

0)0

-X 0)

o.±

E^

(/) o 2o >

-2 ° o §5

§5+7? >

to jQ

.Q

C | 2 o 'C O "U

O)

0) c . 9- 0) £ "O 3 O E E * o o .Si

&§

ii 0) >o

to

CO

to0auc

CO1 a> CL - 22 -

Figure

1.

Mechanisms

of

intracomparLment

smoke

migrati

(from

reference

11)
VALVE

PRODUCED WILL SIMULATE REALISTIC COOLING CONDITIONS FOR THE DOOR

Figure 2. A test concept for measuring leakage of door assemblies

During course of test , valve opening 19 varied to

maintain AP . at the desired value (from

, ^enclosure

reference 24;

- 23 -
Static

pressure

measuring

head

~o o 0 c3

4—> o

k.k_D

"O0

Cl

rL.0

JD o

k.o

(0 E E +-> k_ (0 0 0

*—o o .C c c o

CC 0

<D SZ CO<D <

CO £

a) X) 00

CNI - 24-

Figure

3.

Example

of

an

air

leakage

Lest

chamber

that

might

used

to

carry

out

ISO

DIS

5923/1

(from

reference
00E£o 0— £ « <5 > _ 0 Q_ O > Q.

iz « D C U- C0 o ^ O < 0D0

-CX

LU

C0

O)cD000E0D000 0O>0

Q- “d

25

Figure

4.

General

arrangement

of

the

air

leakage

apparatus

to

be

used

to

carry

out

ASTM E

283-73

(from

reference

27)
o

o

Figure 5. The test equipment arrangement for measuring leakage by

the proposed ISO DP 5925, Part 3 test method (redrawn from

reference 33)

- 26-
Figure 6. Test equipment arrangement for a proposed high

temperature leakage test (from reference 42)

- 27 -
X

<D

CD X

E

ii

o

o

o

C O)

o

D

“O

- 28-

Figure

7.

The

Lest

equipment

arrangement

for

measuring

leakage

by

the

COo,

tracer

gas

method

(from

reference

44)
zzzzzzzzzzzzzzzz:

- 29 -

Figure

8.

Example

of

an

air

leakage

test

chamber

designed

to

test

door

assemblies

at

ambient

and

at

medium

air

temperature

(from

reference

37)
NBS-114A nEv. 2-3C

U.S. DEPT. OF COMM.

BIBLIOGRAPHIC DATA

1. PUBLICATION OR

REPORT NO.

2. Performing Organ. Report No. 3. Publication Date

SHEET See instructions) NBSIR 84-2876 May 1984

4. TITLE AND SUBTITLE

The Need and Availability of Test Methods for Measuring the Smoke Leakage

Characteristics of Door Assumblies

5. AUTHOR(S)

Leonard Y. Cooper

S. PERFORMING ORGANIZATION (If joint or other than SBS, see instructions) 7. Contract/Grant No. NATIONAL BUREAU OF STANDARDS

DEPARTMENT OF COMMERCE

WASHINGTON, D.C. 20234

S. Type of Report & Period Covered

9.

SPONSORING ORGANIZATION NAME AND COMPLETE ADDRESS (Street. City. State, ZIP)

10.

SUPPLEMENTARY NOTES

[~ I Document describes a computer program; SF-185, FIPS Software Summary, is attached.

11.

ABSTRACT (A 200-word or less factual summary of most significant information. If document includes a significant

bibliography or literature survey, mention it here)

This paper identifies and places into perspective relevant information that

would assist in focusing future research and development on test methods to measure

the smoke leakage characteristics of door assemblies. The concept of smoke

compartment at ion is introduced and developed. The importance of cross-door pressure

differential in establishing the performance of door assemblies in fire generated

environments is discussed. Door assembly performance is then related to life safety,

in general, and to the design of compartments of safe refuge, in particular. All of

the discussion suggests a listing of required door assembly test methods, and,

finally, leads to a review of the availability and development status of existing and

potential future test method candidates.

12.

KEY WORDS (Six to twelve entries; alphabetical order; capitalize only proper names; and separate key words by semicolon s) compartmentation, compartment fires, door assemblies, high-rise buildings, leakage,

life safety, pressure differential, pressurization, property protection, safe refuge,

smoke control, smoke movement, stack effect, test methods.

13. availability

X j Unlimited

| | For Official Distribution, Do Not Release to NTIS

Order From Superintendent of Documents, U.S. Government Printing Office, Washington, D.C.

20402.

Order From National Technical Information Service (NTIS), Springfield, VA. 22161

14. NO. OF

PRINTED PAGES

34

15. Price

$8.50

USCOMM-DC «O43-P80