This report has been prepared

for information and record

purpor--~'.. is not to be referenced

publication.

NATIONAL BUREAU OF STANDARDS REPORT

9336

Meetings of

ISO/TC 92, WG 3,4, and 5 The Hague, 23-27 June 1966

by

A. F. Robertson

U.S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS
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for use within the Government. Be and review. For this reason, the pi whole or in part, is not authcrizei Bureau of Standards, Washington

the Report has been specifically pri

June 6 s 1966

NBS REPORT

9336

Meetings of

ISO/TC 92 j WG 3,4 S and 5 The Hague , 23-27 June 1966

by

A. F. Robertson

IMPORTANT NOTICE

Approved for public release by the

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es for its own use.

U. S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS

FIRE RESEARCH MEETINGS IN EUROPE

by

A, F. Robertson

ABSTRACT

Visits were made to Denmark and the Netherlands where

meetings were attended of the Working Group on Fire of the

Conseil International du Batiment and Working Groups 3, 4,

and 5 of ISO/TC 92 on Fire Test Methods. The report summarizes the discussions held and observations made during

visits to three laboratories.

An important new development in European fire research

is the increasing technical concern for problems of accidental

fires. Germany has constructed a beam furnace of 2 - 1/2 x 11

meters size at Braunsweig, while the Danes and Swedes, each,

are planning floor-beam furnaces of 4 x 11 meters size. There

are plans under way to build a furnace to study steel con- structions in an opening of 8 meters high by 4 wide. This

furnace is planned for construction at Metz in Alsace. Not

only are new and larger test facilities in planning as well as currently available but the technical level of the work is of

high calibre. Plans are well in progress to solve problems of

unwanted fires by technical understanding rather than empiricism

The United States is still asleep so far as Government

effort and leadership on building fire studies.

SEVENTH MEETING CIB COMMISSION W14

Copenhagen, Denmark lb- 19 May 1966

The meetings of the Working Group on Fire were held at the

Studenterf oreningen , H.C. Andersens Blvd. b.

We met as a group with delegates from ten different countries as shown in Appendix A. Dr. van Hoogstraten of TNO, Netherlands, was nominated and chosen as chairman.

We then divided ourselves into three groups which proceeded to

discuss: I. Endurance, II. Spread and Measurement of Smoke, III. Fires

in Compartments.

I elected to join Group III for the first day. Mr. Heselden was elected Secretary of this group. He led most of the discussion reporting on the progress to date on the international cooperative enclosure

fire study.

Analysis of the data now available shows that there are no significant biases between laboratories for the radiation and temperature

measurements. However, one laboratory, Australia, did show significant

bias with respect to burning rate data, both with its own data as well

as in comparison with other laboratories. These variations were attributed to changes in box material used.

Heselden reported that previous work had shown that the fuel con- sumption rate kg/min in enclosures could be closely correlated with

A/"h in meters 5/2. The slope of the line was found to be 6 and thus

in analyzing the data, they have elected, for convenience , to plot burning

rate against bAfh or, for normalizat ion purposes , these same coordinates

divided by B the box floor area.

Mr. Heselden discussed the findings reported in [Ij in some detail.

It was suggested the findings implied:

1. The enclosure fires with 1/3 stick spacing seem to correlate

well at 1/4 or less window opening, but show significantly

lower burn rates for larger windows. Perhaps this is associated

with the transition zone we reported in our paper [2].

Similarly, the window radiation level for the cribs with 1/3

spacing was significantly below that for cribs of greater

spacing.

2 .

_ 2 _ 3.

The burning rate seems to increase with stick spacing for

the larger window opening although the radiation level

through the window did not vary greatly for spacings of

1 to 3

.

4.

Thus, the fire severity, which may be assumed proportional

to radiation intensity times fire duration, is greatest for

cribs of 1 spacing.

Mr. Heselden continued discussion by proposing a new cooperative

program [3] intended to explore factors influencing the growth and

spread of fires in enclosures. Both JFRO and TNO have done some preliminary work on this study. Further exploratory work is scheduled

but the plan of the experiment calls for 8 laboratories to carry out a balanced statistical experiment measuring the effects of 8 factors each

at 2 levels and each experiment repeated once. Later work would consist of further exploration of factors found to be important.

I spoke in favor of this project and agreed to the extent permitted

by our facilities to participate. I pointed out various detailed com- ments furnished by Mr. Gross on the proposed program. Others agreeing

to participate included:

1. Joint Fire Research Organization, England

2. TNO, Netherlands

3. National Research Council, Canada

4. State Testing Institute, Sweden

5. Dr. Rumberg, Dortmund, Germany

6. CSTB, France

7.

Mr. Heselden showed some pictures of preliminary experiments performed on this program.

He closed the meeting with a brief review of the findings in their

large-scale burnout tests partially supported by steel interests. This

compartment was of 2,1,1 shape, 2 units wide 1 deep and 1 high, and

the scale was about 4 meters. The window size was arranged for 1/4 and

O %o

n and 1/2 the large wall area. The

results for burning rate R vs. A/h

correspond roughly to that for the

model work. However, in all cases,

the cribs seemed to limit burning

rate

.

T

A CC

- 3 -

If these data are plotted per unit fire load F in kg/nf , then they

plot as shown here:

(cO

ri

' (J &0-

H q

S.IL +BT0

-

f* L ,

?:

.

'

/

—*'

x* YV

*

-—4 - >®o<o

/

4. IV 4

L'

A further correlation was found to

be useful as shown here. This

suggests that the fire duration is

roughly constant up to some critical

ratio of fire load to window area beyond which the fire duration in- creases with F/Aw ratio. It might

be well to compare our enclosure

fire data on this basis.

Temperature measurements in these tests showed that the most

severe fire exposure resulted from the 1/4 window opening rather than

1/2, [4].

During these studies, various steel shapes both protected and

unprotected were exposed to the compartment fire conditions as shown

in the sketch. For columns protec-

[

i : i

T H

L .. J >X

V.

X

I

fjaL ,

2.C300'

H <J i

y|

it V

}

V- -

5U

{< v v

)0G0

HW— „ ^

ted with blown slag insulation, the

temperature of the columns were rather uniform along their length.

In general, there was a fairly good

correlation between column temperature and gas temperature in enclosure,

Data were analyzed on the assumption

that all thermal resistance was in

insulation and all heat capacity in

the steel columns.

The time to peak fire temperature

was reported as linearly related

to ratio of fire load to window

area

A' Aw i _ !

\ ?> OQ

4

As would be

rV

expected

the logarithm of the radiation at the

window opening was found to be

linearly related to gas temperature.

A plot

*T'e t A' v->

, of radiation intensity at the window was reported as linearly related to fire load per

unit floor area. On the basis of

these findings, it was suggested

that the temperature of steel could

be derived from maximum compartment

temperature which could be inferred

from the rate of fuel consumption.

I must admit that although the

reasoning appears appropriate, it

is not clear that the data correlations described should be as straightforward. P/K v^/ M

A brief review was also made of the recent British study of fire

spread below ceilings.

\

Cl C: \ L_

, SYfc\

, P

Apparently, Professor Atallah has

been active in following these tests.

The flame length along the underside

of the ceiling was reported to be 6

to 10 times that which would occur

above the ceiling position, if it were removed.

The flame spread along the wood strip was reported as sould be expected

at left.

5

Experiments had been performed with various types of ceiling

material. The radiation at floor

level 1-1/2 meters from the fire

being recorded.

" vi (Jki'i er^rrD

ft vrSTc;-;‘ "ft, o ^£.a)

i me M ski

On Tuesday we were taken for a visit to the A-S Rockwool Cadanhus,

GI Kangenej 60, Copenhagen V. This company manufactures a wide range

of fibrous insulation materials. The fiber is produced by melting basalt

and limestone with the use of coal in a furnace on a continuous

basis; the molten glass falls in a stream onto water-cooled metal drums

and is blown with compressed air or steam to form the fiber. I believe

the process used is licensed to them by Johns Manville Company. The

fiber has a softening temperature of about 1200 C. We were shown

through their plant and research laboratories. One interesting method

they were using for production control was air permeability as a means

for estimating thermal conductivity. They agreed to forward information

to us on this technique. They admitted that, while it could be used

with high accuracy ±2% on their standard products, it would have to be

recalibrated when applied to a competitor's product. They were performing furnace tests using their "Brandbatt" a low phenyl binder (0.5%)

which was recommended for high temperature insulation„A batt perhaps

12" x 12" was placed as an enclosing door of an electric muffle furnace

operated at 900 C. Observation was then made of the depth of burning

beneath the surface after prolonged exposure. They reported that the

binder content of their regular product was about 2%,.

In the afternoon, we were taken for a visit to the Vedex Dansk

Skovindustri A.S., the Danish Forest Industry Ltd., at Noestred, Denmark.

Their manager, Chr. Christof fersen, showed us through their present

plant where they are producing their new product, Fire-Resistant Compact

Wood (FRCW) . This is a beech plywood the plys of which are individually

impregnated with a newly-discovered secret impregnant formulated from

6

28 different chemicals. The chemical add on amounts to about 17 percent.

Its density is about 120 kg/nt3 and they have tested it under 200 hours

exposure in both boiling water and steam without evidence of loss of

fire retardance or delamination. They attribute its good properties

to both the impregnant and the special glue. They have produced a 35 mm solid door and frame which has performed well in a fire endurance

test for 60 min. Reports were furnished on various tests of this product.

We were told there was never any flaming when the material was tested

and almost no smoke. I asked for a sample of both the untreated and

treated product. These were to be mailed. I informed them that I could

not make an official report of the test results we might plan.

On Wednesday, I was asked to review, briefly, with the Task Group

III, our recent work on smoke measurement methods. Accordingly, I spent most of the morning with this group. They were quite interested

in our proposal for reporting smoke measurements in terms of specific

optical density and, in the report of their meetings submitted later,

they emphasized its usefulness.

During this meeting it became evident that Dr. Rumberg still con- siders the irritation effects of decomposition products of prime concern. Although animals could be useful for assessing toxic hazard, they were

not likely to be useful for study of irritation caused by decomposition

products. It seemed that such measurements could be most usefully made

with groups of people exposed to such gases. It appeared likely that

large numbers of people would be required for such experiments to avoid errors resulting from desensitization resulting from repeated exposures.

Dr. Rumberg reported that they had experienced difficulty in using

chromatographic equipment because of the water present in all combustion

products. He also was critical of the use of colorimetic detector

devices. He said that they have shown seriously low indications in CO

measurement when HCl was present. He indicated that there was evidence

of synergistic effects between CO and HCX . In answer to a question I posed, he indicated that HF had been measured during burning of teflon.

Dr. Rumberg suggested that Germany would probably go along with a qualitative classification scheme proposed by the Swiss. They subjectively rate four properties of plastics as follows:

(a) Flame propagation

(b) Smoke production

(c) Dripping behavior

(d) Toxicity

7

Four classifications 1 to 4 would be used to describe material behavior

with regard to each characteristic for the purpose of selecting plastics

acceptable for building use. Further details of method of reaching

conclusions were not described. Dr. Rumberg is at present actively

preparing two standards for use in Germany, one on decomposition products

and the other on smoke

Mr. Lawson reported continued work with chromatographic studies

of decomposition products in their enclosure fire experiments in which

fire load and ventilation are being varied. Both UK and TNO in Netherlands

are trying to use photometers in connection with their box-type spread

of flame tests. Dr, Lie furnished me with a copy of his preliminary

report on this work. He has performed experiments in which he places

his spread of flame test equipment in an enclosure and finds that the

rate of change of density in the enclosure is proportional to the density

of the smoke column rising above his box. He reported data in agreement

( /\ I \ PLK

Although he has been considering box

volume as we have, he has not yet

correlated data with specimen size

with our finding that plastics produce

most smoke when flaming, while the

'converse is true for cellulosics

/

t

TiKAiC

and, although he apparently is in

agreement with the specific optical

density concept, he had not yet

arrived at this idea on his own.

On Wednesday afternoon, I sat in on discussions of Group I. Here,

the main discussion was on the question of design of heat flux measurement

block for use by laboratories planning to construct walls for comparison

of furnace exposure conditions.

After lengthy discussion, it was decided to go along with proposal

for a block large enough to be used

with our standard pad so that both

heat flux and temperature failure

criteria could be assessed and

compared. Three specimens would be

mounted in each panel and it was hoped that 2 or 3 tests could be run.

It was decided that, as a first try,

only Holland, I.K. , Germany and France

would participate. Germany (DAM) was

to prepare the specimens.

8

On Thursday, all the groups met together and tried to summarize

findings. A report from each was presented by the secretary. These

reports are enclosed as Appendices B, C, and D. Lawson then proceeded

to amplify on the usefulness of knowledge gained through model studies.

He pointed out that their work had made clear the fact that wall linings

and, especially the ceiling thermal properties, had a great effect on

fire development. The time at which flames reach the ceiling is a critical one in fire development because the then rapidly spread over

the ceiling surface. This increases heat transfer back to unignited

material on the floor. Thus, high ceilings tend to delay lateral spread

and growth of fire while low ceilings increase it. The flame height to

diameter ratio of a fire in the open has been shown to be given by:

H/D = K(n? /pgD5

)

1 /

8

where m is the burning rate p is the density and g is the gravitational

constant. From this, he argued that for a given burning rate, as com- partment height increases, the size of the fire at the floor must increase.

However, the time taken for the fire to reach the ceiling and thus start

encouraging lateral growth increases more significantly than the necessarily

larger fire diameter at floor level.

In this way, the greater the height of a compartment, the more

gradual may be the horizontal growth of a fire and thus, at any given time,

the quantity of goods damaged in a high compartment may be significantly

less than one with low ceiling. However, the early detection of fires

with thermal detectors may be more prompt in low ceilinged rooms. This

difference may be serious, but could perhaps be overcome by use of smoke

or other types of detectors.

Because of these considerations, they are currently exploring heat

transfer between flames, ceilings, and floors as H varies.

Lawson said England had recently experienced two cases where roof

venting had failed to control fire spread because of the flammability

of the stored material. They now are planning to explore the use of

water curtains as a means of wetting down a perimeter around the fire

thus delaying spread until the vents can become fully effective.

Lawson closed by emphasizing that they were convinced that the

newly proposed studies for growth of fires were important for showing ways

in which life and property loss could be reduced.

- q

Both the French and Danes, as well as English, plan to clean

up some uncompleted work on the enclosure fire study. It was hoped

that this would make possible analysis of all the data and draft of

a report by the next meeting.

It was proposed that the next meeting be held in Canada and the

United States in connection with the CIB Congress in September 1%8.

On Friday, those of the group wishing to were invited to visit

the fire laboratories of the "State Testing Station" of Denmark. The

facilities have been rather completely described [5]. The fire

laboratories are relatively new having been built in 1957. The space

available is too small, but the equipment seems very good. A floor

furnace of b x 2.5 meter specimen size, a wall furnace of 3.5 x 2.5 meter

specimen size. Numerous small furnaces, spread of flame, and combustibility apparatus.

In spite of the relatively new condition of this laboratory, they

find it inadequate for their needs and are hoping for relocation of

their whole laboratory. At that time they plan to build a furnace for

beams and floors with fire exposed area of 4 x 11 meters.

We were shown their mockup of a ship cabin and corridor for their

stateroom fire tests. The cabin itself is mounted on load cells so that

it rnay be weighed during burnout tests. Previous discussion of laboratory

facilities was included in [6].

10 -

Working Groups of

ISO/TC-92

Meetings of three working groups of ISO/TC 92 were attended as

a result of an invitation from the Secretariat resulting from concern aroused during the IMCO meetings that American thinking be presented

during meetings. I was present, therefore, in observer status, but was encouraged to participate freely in discussion.

The first group No. 3 on "Test Methods for Door Assemblies" met

on Monday and Tuesday, 23 and 24 May. Those, in addition to myself,

participating included Ashton and Malhotra (UK), Malmstedt (Denmark)

Col. Cabret and Bellisson (France XMinne (Belgium) ,Westhoff (Germany), van Hoogstraten (Netherlands) , Shorter (Canada) Sung and van Toutenhoofd

(Secretariat ISO).

Mr. Malhotra was selected as future chairman since Mr. Ashton plans

to retire in the near future.

The meeting started off with a general discussion of problems with

doors during fires. The working group has been charged to develop a test method for doors which will eventually become a part of the fire

endurance test method. It was emphasized that the door frame may be

equally important with the door in containment of fire and smoke.

England and Canada have similar problems since the door and frame are not supplied by the same manufacturers. In both countries, however,

the code requires performance of both door and frame. I described our recent experiments on upgraded doors [7], but emphasized that, although

an ASTM test procedure [8] was available several aspects relative to

qualification of doors were not clearly defined therein and that in our country most doors used for control of fire spread were tested by

Underwriters Laboratories. In France, it was stated that chief concern

was for limitation of spread of smoke and gas through or around the door.

There was considerable discussion of problems relating to control

of position of the neutral pressure zone in the furnace. Apparently,

Britain and Canada have not been able to position this zone easily.

In Denmark, they have perhaps pioneered in control of the location of

this zone, but apparently have had difficulty in moving this below the

1/3 height. Malmstedlt reported that when he tried to raise the furnace

pressure, he got results as shown

to the left. He, Malhotra and Shorter

indicated they planned further experiments taking more care with the measure

ment of static pressures in the furnace

4-

11

I indicated that our panel furnace was designed for the neutral zone

to be below the specimen, but this could be varied by changing draft

conditions

The group had previously initiated studies between laboratories

on use of a canopy above the specimen and fitted with radiation and

convection measuring units. Three simulated doors were to be used as shown sketch. The "doors" were o be of asbestos wood 3/8 in. thick

and of the shapes shown. The

shapes were intended to simulate

the types of cracks likely to develop

with hinged, sliding and folding

doors. British and Danish delegates

compared their initial measurements

with type "A" doors. There seemed

to some evidence of agreement of

heat flow measurements between laboratories and it was agreed to continue

work with some modification of techniques .

\

\

i

1

i ~10C

1 —— 4— ~4

“" 8oo

rufc-Kl

a c

2><?o

The figure summarizes the British studies on ignition of cotton gauze over various crack sizes.

12

It was agreed that France, Netherlands, Germany Denmark, Belgium and

U.K. would participate as planned in the canopy tests for heat transfer

measurement through cracks. Belgium would make measurements with smallscale specimens. Other problems such as grills, hardware, paint, etc., were left for future consideration. The meeting was adjourned with a plan to meet again on / and 8 March in Copenhagen, with perhaps a prior

meeting in October or November of this year, if sufficient progress had

been made by that time.

Papers secured at this meeting included:

ISO/TC 92 WG.3 (Secretariat-89) 194

Test Requirements for Door Assemblies

Report of Paris Meeting 27 and 28 April 1965

ISO/TC 92 WG.3 (UK-1) 1 "Program of Tests to Study the Effect of Door Gaps"

ISO/TC 92 WG.3 (UK-2) 2 "Program of Tests to Study the Effect on the Value

of Doors as Fire Barriers of Gaps at the Edges"

Report No. 1

ISO/TC 92 WG.3 (UK-3) 3 Same as above but Report No. 2

ISO/TC 92 WG. 3 (DK-1) 4

Letter from Malmstedt re; Door Test Instrumentation

13

Working Group 4

The meeting of Working Group No. 4 was held on Wednesday.

This group is concerned with the Reaction to Fire Test Methods

(flammability). However, it was indicated that they had been

charged with the additional problems of collecting information on Smoke and Toxic decomposition products. Those present included

Odeen (Sweden), Minne (Belgium), Malmstedt (Denmark), Amy (France),

Dorn (Germany), van Hoogstraten and Lie (Netherlands), Malhotra (UK),

Shorter (Canada) Sung (ISO Secretariat) and myself.

I agreed to send preprints of our coming paper on smoke as well

as try to send the others to be presented next month at the ASTM

symposium.

The group had previously participated in round robin flammability

tests of 25 materials, in six or eight countries. Since many of the

flammability test methods were of different character, it is not

surprising that some large differences in material ranking resulted.

Mr. Amy had made a statistical study of the results and most of the

morning was spent in discussing his findings (France-1) 1. In doing

this he observed that each test method classification was based on a number of different experimental observations such as flame arrival

time at different stations, stack temperature rise or time at which

temperature rise exceeded a certain level. As a result, it occurred

to him that perhaps the lack of correlation was based on poor selection

of overall index rather than lack of merit of the test itself. He

decided to try to check this and selected a number, 2 to 5^ of these

observations for each test method and then selected pairs of different

tests (laboratories) and then proceeded to calculate the correlation

coefficient between the two laboratories' results for each of the

observations selected. Usually, the coefficient varied significantly

and he then selected the two observations showing the highest coefficient.

In this way he was able to select one of the observations made by each

test method likely to yield the best correlation between all laboratories.

The ranking of the various materials on this basis were then listed and

it was found that the general overall ranking of materials was quite

similar to that originally made. However, by the new ranking method,

several of the initial worst offenders were significantly improved.

There did not seem to be clear evidence that the ranking of plastics was significantly different, as had been the previous observations.

There was considerable discussion on what these findings meant.

In the course of this, the British reported that, as a result of round

robin tests in their own country with their box method, they have found

that a new manner of calculation of classification permits better

correlation. They, therefore, will have to provide Mr. Amy with the new observations for the materials, so he can again review the correlation.

14

The meeting was closed with an agreement that each laboratory

would make a critical review of its own test method with the objective

of deciding whether some other weighing of the various observations

might not result in a more appropriate overall classification. The

participating countries agreed to do this and we were invited to

furnish a technical review of the flammability test methods used in our country.

On Wednesday afternoon, Mr. Lie, of Netherlands, and I were asked

to review, very briefly, our recent work on smoke. I reviewed our work with the box test method, while Mr. Lie described his photometric

measurements in the smoke column above their box flammability test

chamber. He has made a correlation of this as a measure of rate of

smoke production with the slope of the smoke accumulation curve when

the test box is enclosed in a larger container. In general, his

thinking is similar to ours, but the concept of a specific optical

density as a specimen property had not been developed.

The group agreed to try to meet again in November or December

probably at the same time as GS 4 in Copenhagen.

The following papers were distributed during the meeting:

ISO/TC 92 WG.4 (Secretariat-91) 212 July '65

"Report of Meeting Held in Paris 26 and 28 May '65"

Working Group 4.

ISO/TC 92 WG. 4 (France-1) 1 "Part III Statistical Analysis of the Results of

Spread of Flame Test" (WG.4)

ISO/TC 92 WG. 4 (Sweden-1) 2 Octber '64

"Tendency of Surface Finishes to Contribute to Rapid

Flame Spread and Heavy Smoke Development" (WG.4)

15

Working Group 5

The meetings of Working Group 5 were held on Thursday and Friday.

This is a newly constituted group formed to study restraint, deformation

and loading of fire test specimens during endurance tests. The following

delegates participated: Malhotra (UK), Ehm and Pastel representing

Professor Hardina who was ill (Germany), Professor Pettersson and Odeen

(Sweden) , van Sant£ and van Hoogstraten (Netherlands) Shorter (Canada)

and myself as observer.

Prof. Pettersson was elected Chairman. He started the meeting

off by asking each delegate to review the requirements in his country

with regard to specimen loading restraint and structural failure criteria

during fire tests.

Germany DIN 4102

Mr. Ehm reviewed this standard.

1. Floors : Floors are always tested in a freely (support and

rollers) supported condition, no restraint in plane of the

structure. At Braunsweig, their furnace takes specimens of

4-1/2 meters span while the standard requires a minimum size

of 2 x 4 meters. The standard requires that the load applied

be sufficient to stress the structural components to the maximum intended in design. Load failure is based on a rate of

deflection criterion,

Af/At ^ X

2

/ 9000h

where

Af/^t is rate of deflection at midspan

in cm/min.

I is the free span in cm. h is the structural depth of the

specimen cm

2. Walls: Walls are required to be of at least 2x2 meter size.

No restraint is provided against lateral or vertical expansion

of the specimen. Loaded walls are unconfined at sides and

loaded from either top or bottom. Both top and bottom are restrained against rotation. Observations are made of bowing

deflection of walls during test. Wall must remain structurally

stable throughout test. No reload required.

16

ASTM E- 119

Mr. Shorter and I described this test method. We pointed out

that several aspects of the method were not completely defined. Thus,

the way in which load failure is assessed, degree of restraint applied

to specimen, etc., were not clearly defined and could be interpreted

differently between laboratories.

BS - 476

Mr. Malhotra described the British Standard.

1. Beams and floors : These members were freely supported

unless it could be shown that this situation would never

occur in practice. The standard requires that such members

be tested under conditions of restraint simulating those

intended in the construction. Floors are usually tested

with the two edges free and unrestrained or supported.

Loading by deadweights for floors, but hydraulic 4-point

loading for beams. The standard requires that specimens

stand exposure without collapse, but ability to carry test

load 48 hours after test is required. To assess this, the

load is left on floors for this period while beams are again reloaded after 48 hours.

2. Walls ; Load-bearing walls are tested with the two side

edges unconfined. Top and bottom of walls are secured

against rotation. Non-bearing walls are tested fully

restrained. Degree of restraint is not specified. Load

failure not detailed, but structural stability requirement

as for floors. Reload after 48 hours required for walls.

3. Columns : Columns are tested with both ends fixed against

rotation. Both wall and column furnaces can apply a load

of 500 tons. Columns, like other load-bearing structures,

must be tested to determine ability to carry load 48 hours

after test.

17

NEN 1076D

The test method used in the Netherlands was described by Mr. van

Sant<§. He stated that a general requirement was that structures should

be tested under conditions simulating intended practice in use.

1. Floors and Beams ; These members are usually tested without

lateral or longitudinal restraint , usually without moment

restraint at ends. In some cases, floors intended for twoway support are tested with support for all four edges.

When proper loading is applied which recognizes the type of

support, it is usually found that performance is somewhat

poorer than a similar structure loaded and tested in simple

bending. Deadweight loading is used and test method requires

that specimen not collapse. In the TNO laboratory, they have

used the same rate of deflection criteria used by the Germans.

The furnace for beams at TNO is capable of testing specimens

with a fire-exposed length of 8 meters. Longer specimens

have been tested with ends extending over ends of furnace.

2. Walls : Walls are tested with lateral edges free and only low

capacity loading equipment is available. Non-bearing walls

are free to expand on three edges.

INSTA 28/2

9 This new Scandinavian test method is still in draft form. Professor Pettersson described its basic requirements. The standard calls

for specimens of the following maximum sizes:

Floors 2x4 meters

Walls 2-1/2 meters high x 2 meters wide

Columns 2-1/2 meters high

Beams 4 meters span

The test load is to be equal to the design load unless other loading is

shown to be more correct for actual practice. Load is to be applied one day prior to test and remain on for one day after specimen has cooled to room temperature. At this time, the structure shall be loaded to failure.

Although it was stated that walls are to be tested in a manner similar to

that used in Germany and Netherlands, the test specification calls for

restraint of specimens in a manner to simulate that actually existing in

a structural assembly. It was stated that the standard could be interpreted to require axial restraint of expansion of columns. One interesting feature of this proposed standard is the fact that it suggests ways

in which classifications of structures can be based on computation and

tests of similar structures.

18

The meetings of this group were interrupted by a visit on Thursday afternoon to the fire laboratories of TNO at Delft and

the Bow Centrum in Rotterdam. On Friday, they resumed review of

their task. They agreed to circulate standards of other countries

including Australia, Japan, France, etc. They enumerated various

topics for consideration under the three main tasks or aspects of

their duties: loading, restraint, and deformation, and asked that

delegates be prepared to discuss problems in greater detail during

the next meeting, probably at Copenhagen in March 1967.

I agreed to furnish copies of papers developed for ASTM symposium.

Papers distributed during this meeting included:

ISO/TC 92 WG.5 (Sweden-1)2

’’Fire Resistance Test. Determination of Fire Resistance

of Parts of Building Construction" INTSTA 28/2

ISO/TC 92 WG.5 (Sweden-2)3

"Comments on above, showing ways in which it differs

from ISO Std.

ISO/TC 92 WG.5 (USA-1)4

"Fire Tests of Building Materials and Constructions"

ASTM E-119-58

ISO/TC 92 WG.5 (Germany-1)5

"Brandverhalten von Bonstoffen und Bauteilen" (DIN 4102

Blatt 2) Definitions, Requirements and Tests in German.

ISO/TC 92 WG.5 (Germany-2)6

"Brandverhalten von Baustoffen und Bauteilen" (DIN 4102

Blatt 4) Classifications in German.

ISO/TC 92 WG.% (Holland-1)

"Fire Tests on Concrete and Brick Floors" Report No. 19/

1728/1965 TNO.

19

Visit to TNO Fire Laboratories

We visited these laboratories on Thursday afternoon. The only

large furnace of special interest is used for tests of beams. They

have recently completed tests of prestressed concrete beams of about

40 ft length;only 26 feet were fire exposed, the end portions extended

over the furnace ends and were loaded to simulate continuity over supports. The beams had been specially designed with additional negative

moment steel to permit carrying the bending movements at supports even when fire-exposed concrete had been badly damaged. This beam had shown

unusually good performance, 8 hours.

We were shown a small cylindrical furnace used to test plastic

piping used in such a way that it penetrated building floors. Failure

was measured by collapse of piping or temperature rise on outside of

pipe above simulated floor. PVC and one or two other plastics had been

tested, but most failed in less than 15 minutes. This is not surprising

since standard time temperature curve is used in the furnace.

Tuh'iV \ c

5) 0 v-

!

. lie. &

- . IfffTl Fu&»/a. '.r v/a\~

We were shown a new experimental fires building in which an en- closure fire model of 4 x 5 x 2-1/2 meters height could be weighed while

the load was burned. Provisions were being made to use a corridor of

about 10 meters length with this compartment to study fire spread down

the passageway. We were shown several other tests including fabric

flammability and spread of flame (box test). Time was not available for

detailed discussion of findings and nothing else specially new in the

form of test equipment was seen. We were driven by the new TNO laboratories on the border of Delft. These were large and impressive. We were told there were about 10,000 employees in TNO which covers most governmental

technical work.

X trust, in summary, that this record of my visits and meetings

will serve a useful purpose for those willing to struggle through the

pages

20

References

[1] CIB/CTF 66/12 UK "Some preliminary Results of the CIB International

Program Studying Fully-Developed Fires" by Hesselden and Smith,

JFRS Internal Note No. 252.

[2] CIB/CTF 65/39 USA "Experimental Fires in Enclosures" by D. Gross

and A. F. Robertson, 10th Symposium International on Combustion.

[3] CIB/CTF 66/11 UK "Proposals for a Second International Cooperative

Research Program on Fire Behavior in Buildings" by P. H. Thomas

and A.J. M. Hesselden, JFRO, Internal Note No. 251.

[4] Report of Visit to British Fire Research Station, 5 and 6 July 1965,

by A. F. Robertson, NBS Tech. Report No. 8926.

[5] "Statsproveanstaltens nye Brand laborator ium" ,K . Malmstedt ,Saertryk

Ingenioren No. 12 June *61.

[6] "CIB Meeting and European Fire Research 1964" by D. Gross and A. F.

Robertson, NBS Tech. Report No. 8377.

[7] "Doors as Barriers to Fire and Smoke" by H. Shoub and D. Gross,

NBS Building Science Series No. 3.

[8] "Fire Tests of Door Assemblies" ASTM Procedure E-152.

4.5.66 /IJ

APPENDIX A J.nr .B-9/W14

ID 074.66

List: of names and hotel addresses of the participants

in the 7th meeting of C.I.B. Commission W14

Copenhagen, 16th ~ 19th May, 1966

Canada

Mr. G.W. Shorter Hotel Europa

H • C . Andersens Boulevard 5o - 12 68 68

France

M. Bellisson

Colonel Cabret

Commandant Haure

M. le Puloc’h

M. Traverse

) Hotel Richmond

) Vester Farimagsgade 33 - 12 97 ol

) Park Hotel

) Jarmersplads 3 - Mi 3ooo

)

Germany

Dipl.-ing. W. Becker

Dipl.-ing. Hans Dorn

Dr. H. Seekamp

) Park Hotel

) Jarmersplads 3 - Mi 3ooo

) Dr . E . Rumberg

Dr. Wolfgang Westhoff

Dr.-lng. Paul Bornemann

) Missionshotellet

) Lcingangsstrasde 27 - Ce 657o

Japan

Dr. K. Nakata

Netherlands

Hotel Europa

H. C. Andersens Boulevard 5o - 12 68 68

Dr» ($.W. van Hoogstraten } Hotel Alexandra

Ir. Lie T.T.

Ir. F. van Sante

) H.C. Andersens Boulevard 8 - 14 22 oo

)

Norway

Mr. P. Lossius Hotel Hebron

Helgolandsgade 4 ~ 31 69 06

Poland

Mr . L. B aranowsk

i

Missionshotellet

L^ngangs stride 27 - Ce 657o

United Kingdom

Mr. L.A. Ashton

Mr o D .

I

o Lawson

) Hotel Europa

) H.C. Andersens Boulevard 5o - 12 68 68

Mr. j.f. Fry

Mr. A.J.M. Heselden

Sweden

) Park Hotel

) Jarmersplads 3 - Mi 3ooo

Kai Odeen ) State Testing Laboratory, Stockholm, Sweden

V. Sjolin ) Royal Institute of Technology

U, S.A.

Mr. A.F. Robertson Hotel Europa

Ho Co Andersens Boulevard 5o - 12 63 68

Denmark

Dr. Po Becher, The Danish National Institute of Building Research

Hr. Go Danielsen, The laboratory of the Copenhagen fire-fighting service

Hr. Gerhard Hansen,, The Danish State Testing Laboratory

Mr. Ho Lundsgaard, Danish Fire Protection Association

Mr. K. Malmstedt, The Danish State Testing Laboratory

Dr. Jo Mygind, chief of the Freder iksberg fire-fighting service

Mr. Jens V. Petersen, chief of the Nsestved fire-fighting service and

chairman of the association of fire-chiefs

Mr. Jens Holst

Mrs. Annemarie Gjetting

iQ^gtnreters

Mr. RoK. Lockner

Mr. Gerard Ilg

The following will participate in the dinner in Tivoli on Monday, 16th May

Mr. J.H. Ammitzb^ll, chief of the Copenhagen fire-fighting service

to. H.W. Schmidt> yice-chief of the Copenhagen fire-fighting service

Mr. Jurgen Johanseh, chief of the Gentofte fire-fighting service

Mr. Marius Kjeldseri, architect, Ministry of Housing

Mr. R. Serring, chief of the Danish Fire Protection Association

all with ladies

18.5-66 LAA/ag

APPENDIX B

Seventh Meeting of C.I.B. Commission W.l4

Report of Group 1

The following delegates participated in the discussions

:

M. Bellisson

Col . Cabret

M. Traverse

Mr. Becker

Dr Seekamp

Dr. Westhoff

Mr. Lossius

Mr . Baranowski

0r • Robertson

Mr . van Sante

Mr . Shorter

Dr. Becher

Mr . Ashton

( "

"

)

( " "

)

( "

"

)

(part time)

Dr. Bomemann (part time)

Mr. Ashton who was Chairman of the Group at the sixth meeting of W.l4 was asked to resume the post on this occasion. He suggested, however, that in view of impending retirement it would be preferable for the sake of continuity to chose a new Chairman, and Mr • van Sante was proposed and accepted.

At the previous meeting some participants had undertaken to make a review of existing

information on the fire resistance of structural elements for the purpose of supplementing the co-operative project on the correlation of furnaces. Reports of these

reviews had not been prepared in time to be circulated before the meeting, and therefore each author gave a brief account of his study and of his conclusions. Each account

was followed by questions and discussion.

Mr. Bomemann (l) ’compared published results of tests on reinforced concrete floors in

Germany, Holland and the United Kingdom. He used only data for simply supported floors

spanning in one direction, rejecting results of tests in which spalling of the concrete cover occurred. He was not able to give a complete analysis of results in terms of heat

transfer because of lack of knowledge of all factors, but he suggested that a limited

programme of carefully controlled tests could give the information needed.

Dr . Westhoff had been asked to find out whether the results of tests on brick walls,

both with and without plaster, could be used to correlate furnaces. Unfortunately,

there is no recent test information on solid brick walls. Published data are not

complete records and relate to tests made more than 20 years ago. Unless information

on some physical properties of the test specimens could be supplied no useful comparison

was possible.

Mr. Becker (2) examined published reports of investigations on reinforced concrete

columns made in the U.K., the U.S.A. and Germany, but for comparative purposes he found

only the U.K. and German results were relevant. His study took account of structural

behaviour as well as of heat transfer, but two important facts were established, (l)

With a given thickness of concrete cover the rise in temperature of the main reinforcement was always slower in the German than in the British tests. (2) The maximum

elongation of the columns tested in Germany was three times as large as for similar

columns tested in the U.K.

Mr . Ashton reported on the stage reached in the co-operative work on furnace correlation agreed at the last meeting. To design the experiments in the best possible way

he had circulated a questionnaire to the participating countries which asked for answers

to matters relating to the making and preparation of the test structure, the test procedure and the measurements to be made during the tests . Only three countries replied - Holland, Australia and Germany, (West Berlin). The Group discussed the information

supplied by these delegates and by the U.K., and also if the original proposal was likely to achieve its intended objective. After considerable discussion the members agreed

in principle to the original proposal and decided on the essential details of construction for the test elements. A suggestion that the investigation should be extended to

Report of Group 1 2

include combustible elements was not accepted because of doubts about the ability of

participants to complete such tests before the next meeting. Moreover, it was not

practicable for all laboratories to take part since manufacture and distribution of

the test elements on a large scale would be a formidable task. It was decided, therefore, to confine the investigation in the first instance to a limited number of labora

tories, including those with gas- and oil-fired furnaces. The participating countries

are Germany (3 laboratories), Holland, France and U.K., and Germany agreed to make and

distribute the elements . The results of this work should be reported to the next

meeting of Commission W.l4 when the need for an extension to other laboratories could

be examined. Details of the limited programme would be agreed in the course of the

next few months by the participating laboratories who undertook to keep other countrie

informed

.

The suggestion was made that it would be of value if the results of tests nade in different laboratories on constructions containing Rockwool or Navilite could be examined

to see if information on furnace correlation was obtainable.

Refs: (l) Fire Endurance of Reinforced Concrete Slabs. Dr.-Ing. P.Bornernann

(2) Comparative Investigations of the Behaviour of Reinforced Concrete Columns

in Fire Tested at Various Institutes. Dipl.-Ing. W. Becker

APPENDIX C

18.5*66 DEL/JH/ag

Seventh Mooting of C.I.B. Commission W.l4

Report of Group 2

Hn following u.L tended the discussions in group 2:

Mr. G.W Shorter

Dr. E. Rumberg

Mr . H .Lundsgaard

Commandant Hauro

M. 1c Puloc'h

Mr. Gerhard Hansen Dr. K.Nakata

Ir. Lie T.T.

Mr. D. I. Lawson (chairman)

Dr. A F Robertson

Mr. J. Holst (secretary)

Mr. G .W on ortor stated that Canada is interested in smoke hazards in tall buildings , is measuring pressure distribution with a view to keeping smoke from escape routes.

Laboratory work - investigating smoke and toxic hazard of different materials using

a ilow system with atmospheres 0 - 21% oxygen. The toxic measurement will be made by

gas chromatograph

.

No laboratory work in progress, but M. le Puloc'h described some interesting fires involving bundles of PVC insulated cables in a vertical shaft 40 x 60 cm. The HC1

vapours produced had caused great damage to a computer system. M. le Puloc'h said

that tests had been made by the late Colonel Fackler for Electricity de France and a report has been prepared

.

Other tests had been carried out in Rue Lef^vre and the CO produced by the fire had

been measured. A report is available.

M. j_e Puloc h thought that the owiss system was a good one in which the plastic were graded for flammability, smoke, toxicity of combustion products and ability to form

drops of molten material

.

Everybody agreed but the difficulty w

Tas that their knowledge of smoke and toxic hazards was too limited to permit of a grading system being used at present.

-iL_i Rumberg described a lurnace in which a ring oven moves over a tube containing the

test piece of cross-section of 2 mm x 5 rnm. In some experiments the specimen is re- placed by steel for temperature standardization. Dr. Rumberg said that the vapours

must be led directly to animal chambers for the assessment of toxicity. 'The smoke is

led into a tube where it is diluted with a current of air for photometric measurements

.

Dr. Rumberg thinks that gas chromatography is not suitable for measuring toxic gases as some break down in the presence of water- Mass spectrometry is better.

Two standards are in preparation:

1) Thermodegradation,

2) Smoke density.

Dr • Rumberg stated that some toxic products are synergistic, so that their combined

effect is greater than their separate effect, e.g. CO and HC1.

Pf-z Nakata stated that Dr. Handa is working on the visibility in smoke. He believes

that the radius of smoke particles is important, and he will be making measurements

of this.

Mr. Saito is making measurements of the smoke production of building materials heated

to various temperatures. The smoke is collected in a box and the transmission is

measured with a photocell.

Tie lokyo Metropolitan Fire Board have carried out tests in an underground car park.

Report of Group 2 2

The ventilating system made the visibility in fire worse, because the outlets were situated at floor level. It was furthermore found more difficult to move in smoke

than expected.

Mr. Kumano has developed a portable detector for fires in smoke. It costs about 110 ft and is being tried by the Fire Brigade.

Dr • Lie reported that they were adapting their flammability test to measure smoke.

They had tried different wave-lengths of light in the absorption measurements, but

they now use white light. They had also tried venting the smoke products into a compartment 2 x 1 x 1 m. The reduction in density should be calculable and it was

for most materials, but polyurethane was an exception. They will continue testing

other materials.

Mr. D. I. Lawson stated that U.K. is adapting its flammability apparatus for the measurement of smoke . The specimen is subjected to radiation and some of the smoke from the

flue is diluted in a current of air and its light absorption is measured. As far as toxic measurements are concerned a series of fires are being carried out in model

compartments lined with FVC

.

The fuel load and the ventilation of the compartment will be varied. The atmospheres

are being analyzed on a chromatograph. Measurements have already been made of the

production of CO in cellulosic fires. Concentrations as high as 10$ have been produced when the opening in the wall is ~yfto of the total wall area.

Mr. Lawson said that the plastics industry were striving to produce low flammability

plastics by adding chlorine, bromine, phosphorus and antimony either in molecular

combination or as an additive. They were so far content if the toxic product from the

plastic, itself was low, but it is probably more important to see that the toxic products from the plastics are low when involved in a fire, not necessarily of their own making

.

Dr. Robertson said that it is important that the surface of materials should not produce smoke. This allows many manufacturers to improve surface treatments. Samples were exposed to radiation 2,5 watts/cm

2

in a compartment, and the smoke density measured in a vertical direction to overcome the effects of stratification. Dr. Robertson

thought it important to measure the specific optical density, i.e. the optical density

per meter. This is a dimensionless quantity involving the ratio of light intensities

and the volume of the compartment divided by the pathlength and the area of the specimen. Dr. Robertson said that some materials, e.g. polystyrene emit more smoke when

flaming whereas others, e.g. fibre insulation board emit more when smoldering.

Conclusions

1. Toxic products and irritants would probably be as important, and perhaps even more

important than smoke in preventing escape.

2 . The only way of getting an assessment of irritants would be to use human volunteers.

5 • Fire Brigades should be asked to withdraw samples of plastics from fires in which

these had been involved and submit them for examination together with a report on

the breathing difficulties

.

4 . In any model fires the CO content should be measured in the future

.

5* It was thought that the^American system of measuring specific optical density was

•useful. The quantity would lead direct to building regulations, in which V is

the volume of the compartment, A the area of plastic allowable and L a pathlength

of vision related to the distance of viewing the word EXIT at the illumination

level on staircases, etc.

lo . ^ . Ob AJ Mli/ ag

APPENDIX D

Seventh Meeting of C.I.B. Commission W.l4

Report of Group 3

The following delegates participated in the discussions:

M. Bellisson

Mr. Danielsen

Dipl.-Ing. Dorn

Mr . Fry

Mr Heselden

Mr. Malms tedt

Dr . Mygind

(part of the time)

^

tt it it it ^ (Secretary)

( part of the time)

Dr - Robertson

Dr. van Hoogstraten

Mr . Odeen

Mr. Sjolin

Dr . Rumberg

Mr . Lossius

( part

( ” of the time

)

n ii it \

Cooperative research programme (fully-developed fires)

An analysis of the Scries 1 results had now been carried out and had shown that there were no significant differences between the results of the various laboratories except

in those cases where different box lining materials had been used.

Further experiments of Series 1 and 2 had been carried out and a report had been issued

which surveyed the available data and showed that some scaling laws could be found.

Data were lacking in some areas and Mr. Heselden suggested that it was desirable that

the following experiments should be carried out:

(1) 121 shape , 1~| m scale. The original design should be modified to include fewer

fire load densities, since this factor appeared to be relatively unimportant for

this shape, and another level of window opening.

(2) 44l shape, 1-p m scale. These experiments were part of the original programme and

would be carried out by the J.F.R.O. this summer.

(3) 211 shape. Data are as yet incomplete, but the C.S.T.B. is at present carrying

out 1 m scale experiments and when these are finished it will be easier to see how well the data can be correlated. In any case the C.S.T.B. would carry out

two extra tests

The J.F.R.O. would carry out some experiments to find the reason for the fall in

burning rate with increasing window opening.

Second cooperative research programme

Mr Heselden introduced proposals for a new cooperative research programme studying

the early stages of growth of fire in a compartment. Some work had already been carid ed out by T.N.O. In the first part of the programme 8 laboratories would carry out

a balanced statistical design measuring the effects of 8 factors each at 2 levels.

In the second part the effects of factors shown to be important would be studied in more detail. Special attention would be given to the effect of various lining materials, both flammable and non-flammable, on the rate of growth. Other factors studied

would include shape of compartment, fireload density, position and size of ignition

source. The fuel would consist of both continuous and discontinuous beds. Some

trials had been made and it had been found necessary to modify a few of the experimental details of the proposals made in CIB paper 66/11, but the main proposals were unaltered.

Dr. van Hoogstraten said that there was much uncertainty as to what the results of the

various 11 reaction to fire" tests meant in terms of real fire behaviour. It was for

this reason that his laboratory had already made studies of the growth of fire to flashover. He thought that experimental work in this field was highly desirable and said

that he would try to obtain experimental support at the meeting of the ISO working

Report of Group 5 2

group next week.

Dr. Robertson said that he was very interested in this problem and would be glad to

participate in a cooperative programme of the kind suggested, although his position

was not very certain at present. He suggested that it was necessary to check that

1 m scale compartments were sufficiently large before embarking on the programme.

Various suggestions for possible measurements were discussed.

Mr. Malmstedt said that he would probably be able to take part in the programme but

he could not undertake both this and the l|r m scale tests of the first programme

which he had been planning to do.

Mr. Shorter , Dr. Rumberg and Dipl.-Ing. Dorn considered that their laboratories might

be able to participate. It was agreed that Dr. Isaacs should be asked if he could

take part.

Mr. Malmstedt suggested that temperature and velocity measurements in a duct leading

the combustion gases away should be made to measure the rate of heat production of the

fire. The group considered these measurements might be helpful but that it might be

necessary to keep the experimental arrangements very simple in the early stages of the

programme. A pilot experiment would be helpful in deciding what measurements should

be made

.

Dr. Rumberg said that Group 2 had proposed that measurements of smoke density, CO and

possibly CO? concentration should be made in the tests of the second cooperative re- search programme . It was agreed that such measurements ought to be made and that the

methods to be used and the point of measurement should be decided during preliminary

experiments

.

Fires in compartments (General)

Mr. Heselden described a series of experimental fires made at the J.F.R.O. in a com- partment about 8 x 4 x J m containing steel members.

Various correlations had been obtained between fire duration, fire temperature, steel

temperature, and fireload density and 'window opening.

Below a critical value of fireload per unit window area of about 150 kg/m2 the fire was controlled by the fuel bed and the fire duration was constant. At higher values

the fire was controlled by the window opening and the duration increased with increasing fuel quantity or decreasing window size.

Mr Odeen described experimental fires he had carried out in a compartment 9 m long

with various amounts of fuel and with various controlled rates of air supply. He was going to relate the temperature -time relations obtained to those in other fires, and

would be making a study of the flow of heat into the walls of the compartment.

In a discussion on flashover Mr. Sjolin said he had found that altering the dispositions

of the fuel could produce or eliminate flashover.

Mr- Heselden described the studies being made at the J.F R.O. on the early stages of

growth of fire in a compartment. The downward radiation from flames travelling under

a ceiling was thought to be of great importance in determining the rate of spread of

fire at ground level and on the rate of growth to flashover.