close coupled field accredited research results...penicillium chrysogenum, bacillus subtilis var...

CLOSE COUPLED FIELD

ACCREDITED RESEARCH RESULTS

This document contains summaries of reports presented by laboratories carrying out

validation research into the efficacy of the technology

The laboratories concerned, and their respective reports, are:

Microsearch Laboratories Ltd

A. A Summary of the Anti-Microbial Performance of the AirManager

Technology applied to a range of Micro-organisms and Viral Particles

B. A Study into the Removal of Tobacco Smoke Analytes

University of Central Lancashire

A. Assessment of Ozone Leakage from the AirManager Unit

B. Passive Sampling of Ozone Leakage over a prolonged period

CCFRA Technology Ltd

A. A Summary of the Anti-Microbial performance of the AirManager

Technology applied to Pseudomonas aeruginosa, Staphylococcus aureus,

Penicillium chrysogenum, Bacillus subtilis var globigii and Neurospora

(Chrysonilia) sitophila.

Mountain Heath Services Ltd

A. Volatile Organic Compounds tested at 100 x maximum OEL

Microbial Innovations Ltd

A. Methylene Chloride Removal using Close Coupled Field technology.

Clean Air Solutions Ltd

A. Particle reduction and arrest capabilities of Close Coupled Field

technology.

A summary of the performance characteristics of the

Airmanager range of atmospheric treatment devices

Quest International (Airmanager) have developed a range of devices designed for

microbiological decontamination of atmospheres. This technology employs closed

coupled field technology for the contained generation of Ozone and ions, in tandem

with terminal electrostatic filtration. of the air stream.

Combining these technologies in a manner which affords a high flow rate permits

the effective treatment of large volumes of atmosphere in a manner which we

believe represents a significant advance in the area of air management.

This document summarises the anti-microbial performance data, obtained by an

independent assessment laboratory.

Ozone production characteristics

Ozone is a highly oxidative molecule and may be generated by UV radiation or the effects of electrical

discharge on molecular Oxygen in air.

The Airmanger device generates ozone by electrical discharge employing patent pending technology.

The European standard for atmospheric levels of ozone is currently 0.2 ppm while according to

various literature sources the required dosage of ozone required to inactivate microbial systems, on

contact , varies between 0.05 ppm and 0.4 ppm.

An important aspect of this validation effort has been to demonstrate compliance of the device with

European ozone emission standards, whilst additionally producing evidence of sufficient ozone

generation to accommodate effective competence with regard to the task of broad scope anti-

microbial activity.

A key advantage of the Air manager Device is the claim that ozone generation and reactions with

micro-organisms, occur contained solely within the device resulting in decontamination with no

measurable emission of ozone.

Addtionally it is claimed that the electrostatic filter stage serves only to capture oxidised debris and

remove particulates from the air.

Ozone measurements

These claims have been investigated employing a novel probe by which ozone production is

determined by measurement of the degree of oxidation obtained with a d-alpha tocopherol coating

during exposure Trials have been conducted to measure ozone production within the device and the

potential for environmental accumulation during use, with and without filter in situ.

The following tables summarise our findings.

Measurement of ozone production by d-alpha Tocopherol probe oxidation with filter in place

Run Time hours

03 ppm within

treatment chamber 0

3 ppm within 60 m

3

Room

0 24 <0.2

6 103 <0.2

12 94 <0.2

18 107 <0.2

24 102 <0.2

Measurement of ozone production by d-alpha Tocopherol probe oxidation without filter in place

Time hours

03 ppm within

treatment chamber 0

3 ppm within 60 m

3

Room

0 41 <0.2

6 96 <0.2

12 97 <0.2

18 104 <0.2

24 106 <0.2

Our data indicates no significant emission of ozone from the device could be measured over a 24

hour period in the operating environment.

Measurement indicates that significantly higher levels of Ozone are produced within the closed

coupled field device than predictably are required for contact inactivation all classes of micro-

organisms for which susceptibility has been published.

Microbiological aspects of Filter performance

Electrostatic air filtration is know to produce reduction in the levels air borne microbial contaminants.

A possible problem with stand alone filtration devices is therefore the accumulation of possibly

infective or otherwise unwanted viable contamination within the structure of the filter during life

span. We have conducted trials to monitor these possibilities and present below the data obtained

showing the recovery of differing classes of organism from the interior surfaces of the terminal filter

are different periods of operation in waste processing room.

Recovery of viable micro-organisms from electrostatic filter material after differing periods of usage

Operation interval

TVC cm3

Filter material

Moulds cm

3 Filter

material

Yeasts cm

3 Filter

material

Bacillus sps cm

3 Filter

material

Gram neg sps cm

3 Filter

material

Gram Pos sps cm

3 Filter

material

1 day <10 <10 <10 <10 <10 <10

1 week <10 <10 <10 <10 <10 <10

1 month <10 <10 <10 <10 <10 <10

4 months <10 30 <10 20 <10 80

Conclusions

Our data demonstrates that in an environment know to exhibit high levels of airborne microbial

contamination significant build up of viable organisms occurred in the filtration unit up to and

including three months of use. This effect may caused by impingement of residual zone on the active

surfaces, loss of viability due to dehydration in the high flow rate of air, nutrient scarcity or a

combination of these and other factors.

Such findings to some degree support the anti-microbial efficiency of the ozone generation system

presented below. More importantly these findings suggest that in respect of bacteria and fungi the

filtration stage is unlikely to represent a biological hazard during replacement.

Demonstration of Anti-microbial competence

The following experimental data reports on the performance of the M4/4 device in relation to the

reduction of single pass microbial challenges. Performance at each of four levels level of flow rate has

been determined for a range of organisms with and without electrostatic filtration in place.

M4/4 Single pass performance with electrostatic filtration

Organism Challenge level cfu/l-

1 Speed 1 Recovery

cfu/l-1

Speed 2 Recovery

cfu/l-1

Speed 3 Recovery

cfu/l-1

Speed 4 Recovery

cfu/l-1

A.niger 8.80E+06 <1 <1 <1 <1

S.typhimurium 7.40E+06 <1 <1 <1 <1

C.Albicans 6.00E+06 <1 <1 <1 <1

S.aureus 7.10E+06 <1 <1 <1 <1

B.cereus 2.20E+06 <1 <1 <1 1.30E+02

M4/4 Single performance with no electrostatic filtration

Organism Challenge level cfu/l-

1 Speed 1 Recovery

cfu/l-1

Speed 2 Recovery

cfu/l-1

Speed 3 Recovery

cfu/l-1

Speed 4 Recovery

cfu/l-1

A.niger 7.00E+06 <1 <1 <1 <1

S.typhimurium 8.40E+06 <1 <1 <1 <1

C.albicans 8.30E+06 <1 <1 <1 <1

S.aureus 9.20E+06 <1 <1 <1 <1

B.cereus 4.70E+06 <1 <1 3.10E+02 9.80E+02

Speed 1 = standard flow rate 190 m3

Conclusions :

All conditions of treatment produced significant levels of reduction in the levels of air borne

challenges.

Under these challenge conditions Increment 3 gave a 100 % performance with filter in place while

increment 2 gave a 100 % performance with no filter in place.

With filter in place all organisms were reduced to non detectable levels at increment 4 with the

exception of Bacillus cereus where only a 4 log reduction was achieved.

My recommendation is to limit flow to increment 3 (570 m3/hour) with the filter in situ, to guarantee a

consistent and rapid degree of air processing.

Continuos dosage lethality with a range of micro-organisms

In this series of trials a wide range of microbial types were continuously introduced at the intake

section of the Airmanager device for a period of 1 hour. During the exposure time periodic

measurements were taken at the output section and the levels of survivors were determined. The

following results were obtained.

Airmanager performance against continuos input of Bacteria and Fungi

Organism Class Mean cfu/m3/Hr

at input Treatment stream

Mean cfu/m

3/Hr

post Treatment exit stream

Mean decline Log/cfu/m

3/Hr


Apparent percentage reduction

Escherichia coli Gram –ve 2.1E+05 0.0E+00 >5 >99.999

S.tyhpi murium Gram –ve 4.6E+05 0.0E+00 >5 >99.999

E.agglormerans Gram –ve 3.9E+05 0.0E+00 >5 >99.999

E.gergoviae Gram –ve 4.2E+05 0.0E+00 >5 >99.999

A.aerogens Gram –ve 7.1E+05 0.0E+00 >5 >99.999

S.marcescens Gram –ve 8.2E+05 0.0E+00 >5 >99.999

E.sakazakii Gram –ve 3.4E+05 0.0E+00 >5 >99.999

Ecoli 0157 H:7 Gram –ve 3.5E+05 0.0E+00 >5 >99.999

P.aeruginosa Gram –ve 6.1E+05 0.0E+00 >5 >99.999

P.putida Gram –ve 8.2E+05 0.0E+00 >5 >99.999

S.aureus oxford Gram +ve 4.3E+05 0.0E+00 >5 >99.999

S.aureus MSRA Gram +ve 4.8E+05 0.0E+00 >5 >99.999

S.epidermidis Gram +ve 3.7E+05 0.0E+00 >5 >99.999

M.luteus Gram +ve 9.0E+05 0.0E+00 >5 >99.999

S.faecalis Gram +ve 7.3E+05 0.0E+00 >5 >99.999

S.pyogenes Gram +ve 3.6E+05 0.0E+00 >5 >99.999

B.cereus Gram +ve 7.1E+05 0.0E+00 >5 >99.999

B.globigii G+ve Spore 7.9E+05 1.0E+01 >5 99.999

B.subtilis G+ve Spore 2.1E+05 3.0E+01 >5 99.986

B. megaterium G+ve Spore 6.2E+05 9.0E+01 >5 99.985

S.cerevisiea Yeast 4.3E+05 0.0E+00 >5 >99.999

S.bailli Yeast 7.2E+05 0.0E+00 >5 >99.999

Pichia mixed sps Yeast 6.3E+05 0.0E+00 >5 >99.999

S.ludwigii Yeast 6.0E+05 0.0E+00 >5 >99.999

A.niger Mould mycelial 6.2E+05 0.0E+00 >5 >99.999

A.flavus Mould mycelial 7.8E+05 0.0E+00 >5 >99.999

F.poea Mould mycelial 7.2E+05 0.0E+00 >5 >99.999

P.digitatum Mould mycelial 6.9E+05 0.0E+00 >5 >99.999

F graminerium Mould mycelial 4.3E+05 0.0E+00 >5 >99.999

A.niger Mould Spore 8.2E+05 7.0E+01 >5 99.991

A.flavus Mould Spore 6.7E+05 5.0E+01 >5 99.993

F.poea Mould Spore 8.2E+05 0.0E+00 >5 >99.999

P.digitatum Mould Spore 6.7E+05 0.0E+00 >5 >99.999

F graminerium Mould Spore 2.9E+05 0.0E+00 >5 >99.999

Airmanager performance against continuos input of viral particles

Organism Class Mean cfu/m3/Hr

at input Treatment stream

Mean cfu/m

3/Hr


Mean decline Log/cfu/m

3/Hr


Apparent percentage reduction

CTX SS DNA 4.3E+12 8.1E+02 >12 >99.999

ScV-L-BC DS RNA 9.2E+12 4.6E+02 >12 >99.999

FcoV (attenuated) SS + RNA 7.1E+12 3.0E+02 >12 >99.999

T4 Phage DS DNA 5.3E+12 7.4E+02 >12 >99.999

Conclusions

The air manager device has demonstrated a high level of competence in the inactivation of a wide

range of micro-organisms including, Bacteria cells, Bacterial spores, virus particles, Mould, Mould

spores and Yeasts. Kill efficiencies in excess of Log 12 were obtained consistently for all classes of

viral particle examined, while for all other classes of organism no less than a Log 5 kill was obtained

on a continuous basis. In summary the device is highly effective at killing micro-organisms.

In Use Assessments

Detailed below are the results of environmental trials during which the capacity of the Airmanager

device was assessed in relation to the clean up of natural airborne population of micro-organisms.

The efficiency of the Airmanager ‘M4’ air treatment unit in the

sanitisation of a Laboratory incubator room

Introduction :

In spite of good compliance to GLP standards it is possible that laboratories may still develop

problems associated with airborne microbial contamination. Usually such problems are detected by

routine environmental surveillance or incidences of contamination on solid agar plates.

In this study a problem was investigated relating to a persistent environmental contamination in a

commercial grain testing laboratory. This facility had reported significant levels of in lab mould

contamination of both blank plates and plates intended for the isolation of yeasts and moulds from

samples. In house environmental analysis by settle plate had determined the presence of identical

isolates to those found on the plates in the atmosphere of the incubation room.

This isolate responsible for the contamination was confirmed as Fusarium poae. This organism is

common in temperate regions and is associated with commodities such as Wheat and Maize both of

which were commonly handled by the facility. It demonstrates growth over the range 2.5 'c to 33'c and

characteristically, on common mycological media produces profuse growth with Salmon or pale pink

colonies.

Trial outline :

The trial was conducted in two stages. During the first month of monitoring the M4 device was not in

operation and air sampling was conducted on an hourly basis between the hours of 9.00am and 6.00

p.m. over a six day working week Sampling was conducted employing a Cassela volumetric

sampler with impaction onto Oxytetracycline glucose yeast agar. During week one (device off) 0.1,

0.2, and 0.5 L-1

air volumes were taken at the specified interval.

The device was operative during month two. Sampling was conducted to the same schedule described

above with an identical sampling procedure.

Simultaneously during the trial records were kept of non compliant contaminated agar intended for

use in analytical procedures.

Results :

Table : Mean air quality in a laboratory incubation area and media quality over a two month period

with and without the M4 device in operation.

Device status

Week F. poae cfu/L-1

/Air Percentage in lab plate

contamination

OFF 1 17100 3

OFF 2 21300 2

OFF 3 16700 9

OFF 4 18900 3

Mean 18500 4.25

ON 5 20 <1

ON 6 40 <1

ON 7 2 <1

ON 8 3 <1

Mean 16.25 <1

Conclusions ;

In this laboratory an overt problem had been experienced in relation to media contamination which

was directly related to environmental cross contamination with Fusarium poae.

The operation of the M4 device in the area which was the source of this problem successfully reduced

the level of contamination on a consistent basis by between 2 and 3 log cycles L-1 air

. This magnitude

of effect was sufficient to reduce the level of media contamination to a non detectable level.

On this basis the M4 device has been shown to be an effective tool in the maintenance of a

microbiological laboratory air quality.

A laboratory investigation of the Microbiological and Sensory

efficiency of the Quest Ozonation device

Quest International (UK) Ltd have developed a innovative device which through a novel piece of

engineering is capable of treating atmospheres with very high doses of Ozone with a free fan

transfer volume of 190 m3/hour. Additionally the device is capable of operating with either 'cutting

edge' replaceable Electrostatic filters ( FR = 160 m3/hour) or alternatively with H.E.P.A. filters ( FR =

65 m3/hour) as a final air treatment.

It was theorised that usage of the device with Electrostatic filtration in combination with ozonation

would afford both reduction of airborne micro-organisms and good odour decontamination

characteristics while employment of H.E.P.A. filtration was anticipated to produce superior

microbiological performance.

Prior to this work no microbiological performance data had been obtained but it was known that

ozonation in combination with electrostatic filtration produced superior sensory results.

Quest International (UK) ltd invited Microsearch laboratories Ltd to conduct pilot testing to determine

the anti-microbial efficiency of the device.

We have achieved this goal by monitoring the reduction of air borne Gram negative bacteria

attributable to the Quest device over a seven day period in a microbiological laboratory waste

processing room. Measurement has included the performance characteristics of both filtration system

and has also included determination of sensory factors.

Trial 1 : Efficiency of the Quest Device in the sanitisation of the atmosphere in a Class II

microbiological laboratory waste room.

Outline :

The vast majority of contemporary microbiological laboratories are equipped with a designated area

designed to afford physical segregation of contaminated biological waste intended for sanitation by

autoclaving preceding safe disposal. Such waste consists of agar plates, cultures and implements

employed in microbiological manipulations.

In general such waste is extremely biologically active prior to treatment and may contain billions of

organisms per gram. While every effort in GLP is to prevent transfer of contaminants the nature of the

autoclaving process requires that storage bags are open to the atmosphere at the start of processing. As

a consequence the opportunity exists for introduction of large masses of organisms or spores into the

environment. Factually such areas exhibit high levels of airborne contamination.

These distribution factors coupled with the thermal currents created by autoclave operation engender a

demonstrably abundant and sustained level of airborne micro-organisms of many differing types. It is

true that such contamination is unlikely to present as a direct health risk through inhalation but such

an environment provides a useful model for efficiency studies of devices which purport to reduce

airborne levels of micro-organisms.

In this trial the regime involved the sampling of the atmosphere in the test environment by impaction

of air onto the surface of agar plates through the use of a Cassela air sampling device. The Cassela unit

is capable of accurately sampling a known volume atmosphere over a 30 second period and

continuously delivers the sampled air to an enclosed chamber. In this chamber an agar plate is exposed

to column of intake air whilst rotating thus distributing micro-organisms evenly over the surface of the

plate. Subsequent incubation of the plates allows enumeration of numbers of organisms present in the

original volume of atmosphere examined. Through the use of differing types of agar and a diagnostic

tests it is possible differentially count different types or classes of micro-organism.

Room Conditions : The room comprised of a 24.3 m3 cube. It contained an autoclave with treated

waste in one half and 25 Kg storage bags of untreated waste in the remaining floor area. At any one

time the area contained a minimum of 16 untreated waste bags of which between 8 and 10 bags would

be handled and processed in a working day between the hours of 9.00 am and 6.00 p.m. The sampling

device waste located centrally. Normally the room atmosphere is vented by forced extraction, this was

not the case during this trial. The autoclave hot exhausted was vented via an enclosed circuit which

we believe did not effect the atmospheric composition of the test environment.

Sampling Plan : Sampling occurred over a twenty four hour period at the intervals given in table one

below.

Such sampling extended over a seven day period with the Quest device running without any form of

filtration in place and without the ozone generator switched on. This was intended as a protocol to

demonstrate the background level of contamination. The data obtained is given in tables 1 and 3

below. The data gathered in this exercise was employed as the comparison set for all information

gathered during the subsequent period when the Quest device was operational as a sanitising unit.

Two further identically scheduled sampling periods were conducted sequentially separated by a four

day recovery gap. Firstly the device was operated with ozone on and an Electrostatic filter in place. In

the second session the device was operated with a H.E.P.A. filter in place again with an identical

sampling plan.

Microbiological analysis : The agar employed in all test was Violet Red Bile glucose agar ( VRBGA)

intended for the recovery of Gram positive organisms from the atmosphere through the use of the

Cassela device. Colonies were recovered on this agar after incubation at 35 ‘c for 24 hours. As the

trials were intended primarily to show overall comparisons , It was assumed that all isolates obtained

on VRBGA were Gram negative and all isolates were counted. Colonies were further differentiated on

the basis of Oxidase reaction. All sampling was conducted in duplicate.

Results : Table 1 below and associated graph provides the data obtained for Gram negative (Ox +ve

and Ox –Ve) isolates during the unsanitised control period and that for the data obtained during the

period of Ozone treatment associated with electrostatic filtration of the return air flow. Table 2

illustrates the average percentage kill through out the day attributable to the action of Ozonation and

Electrostatic filtration. Tables 3 and 4 summarise the same categories of data obtained for the period

when sanitisation was attempted employing Ozonation and H.E.P.A filtration.

Table 1:

Mean Microbial Levels over a 24 hour period in a microbiological waste room

( 23.4 M3) with and without continuous operation of the Quest Device

with electrostatic filtration

Time Condition Oxidase Pos Gram negative isolates L

-1/air

Oxidase Neg Gram negative isolates L-1/air

06:00 AM o3 off EF- 4.7E+03 8.6E+03

10:00 AM o3 off EF- 5.6E+03 9.2E+03

02:00 PM o3 off EF- 9.8E+03 2.8E+04

06:00 PM o3 off EF- 2.0E+04 3.7E+04

08:00 PM o3 off EF- 1.8E+04 3.3E+04

02:00 AM o3 off EF- 9.2E+03 1.9E+04

04:00 AM o3 off EF- 3.7E+03 8.7E+03

06:00 AM o3 on EF+ 6.0E+02 1.3E+03

10:00 AM o3 on EF+ 7.7E+02 1.3E+03

02:00 PM o3 on EF+ 1.6E+03 4.4E+03

06:00 PM o3 on EF+ 3.4E+03 6.2E+03

08:00 PM o3 on EF+ 3.4E+03 5.8E+03

02:00 AM o3 on EF+ 1.4E+03 3.0E+03

04:00 AM o3 on EF+ 4.8E+02 1.2E+03

06:00

AM10:00

AM02:00

PM06:00

PM08:00

PM02:00

AM04:00

AM

0.0E+00

5.0E+03

1.0E+04

1.5E+04

2.0E+04

2.5E+04

3.0E+04

3.5E+04

4.0E+04

time of day

Mean Gram negative levels per L-1

/air over a 24 hour

period in a 24.3 m3 waste room

OX Neg G Neg No t reat ment

OX Pos G Neg No t reat ment

OX Neg G Neg t reat ed

OX Pos G Neg t reated

Table 2 :

Mean Microbial % reduction levels over a 24 hour period in a microbiological waste

room ( 23.4 M3) with the QUEST DEVICE operating and with electrostatic filtration


-1/air


06:00 AM o3 on EF+ 87.3 85.1

10:00 AM o3 on EF+ 86.2 85.4

02:00 PM o3 on EF+ 83.2 84.3

06:00 PM o3 on EF+ 82.8 83.2

08:00 PM o3 on EF+ 81.3 82.2

02:00 AM o3 on EF+ 85.3 84.6

04:00 AM o3 on EF+ 86.9 85.8

06:00 AM10:00 AM

02:00 PM06:00 PM

08:00 PM02:00 AM

04:00 AM

OX Neg G Neg

Ox Pos G Neg

78

79

80

81

82

83

84

85

86

87

88

Time of day

Mean Gram -ve % reduction per L-1/air over 24 hours

in a 24.3 m3 waste room

OX Neg G Neg

Ox Pos G Neg

Table 3:

Mean Microbial Levels over a 24 hour period in a microbiological waste room

( 23.4 M3) with and without continuous operation of the Quest Device

with H.E.P.A filtration


-1/air


06:00 AM o3 off HEPA- 4.7E+03 8.6E+03

10:00 AM o3 off HEPA- 5.6E+03 9.2E+03

02:00 PM o3 off HEPA- 9.8E+03 2.8E+04

06:00 PM o3 off HEPA- 2.0E+04 3.7E+04

08:00 PM o3 off HEPA- 1.8E+04 3.3E+04

02:00 AM o3 off HEPA- 9.2E+03 1.9E+04

04:00 AM o3 off HEPA- 2.1E+03 8.7E+03

06:00 AM o3 On HEPA + 3.1E+03 5.7E+03

10:00 AM o3 On HEPA + 3.9E+03 6.2E+03

02:00 PM o3 On HEPA + 7.0E+03 2.0E+04

06:00 PM o3 On HEPA + 1.6E+04 2.8E+04

08:00 PM o3 On HEPA + 1.5E+04 2.7E+04

02:00 AM o3 On HEPA + 6.5E+03 1.4E+04

04:00 AM o3 On HEPA + 1.4E+03 5.7E+03

06:00

A M10:00

A M02:00

P M06:00

P M08:00

P M02:00

A M04:00

A M

0.0E+00

5.0E+03

1.0E+04

1.5E+04

2.0E+04

2.5E+04

3.0E+04

3.5E+04

4.0E+04

tim e of day

Mean Gram negative levels per L-1

/air over a 24 hour

period in a 24.3 m3 waste room

OX Neg G Neg No t r eat ment

OX Pos G Neg No t r eat ment

OX Neg G Neg t r eat ed

OX Pos G Neg t r eat ed

Table 4 :

Mean Microbial % reduction levels over a 24 hour period in a microbiological waste

room ( 23.4 M3) with the QUEST DEVICE operating and with H.E.P.A. filtration.

06:00 AM o3 On HEPA + 34.5 33.9

10:00 AM o3 On HEPA + 30.3 33.1

02:00 PM o3 On HEPA + 28.6 28.7

06:00 PM o3 On HEPA + 22.1 24.6

08:00 PM o3 On HEPA + 19.2 17.4

02:00 AM o3 On HEPA + 29.6 28.2

04:00 AM o3 On HEPA + 34.8 34.2

Trial 2 : This work was intended as a primer and involved the introduction of a number of single

calibrated doses of Aspergillus niger hyphae fragments and spore particles into a chamber having a 8

l-1

volume. The chamber was constructed in a manner as to permit access of the Quest device intake

grill to the interior of the chamber while the output section vented directly into a second chamber of

identical volume. Both chambers were vented by membrane filters for the purpose of pressure

equalisation. The purpose of the trial was to attempt to demonstrate a single pass efficiency in lethality

in a known airborne pathogen.

Dosing conditions : The biological material was delivered in the form of a fungal hyphae and spores

dispersed in Calcium silicate matrix. Both Chambers equipped with fans intended to assist dispersion.

Sampling was conducted via suction with collection in a 2 % sucrose/saline solution an involved 2 L-1

volume for each chamber. The device was not operational during dosing for 2 minutes after the

introduction of the biological material but had been previously stabilised for 30 minutes . After the

post dose period the device was operated for period of 1 minute and after which the atmosphere in the

delivery chamber was samples.

Analysis : Recovery solutions were examined by serial dilution and survivors were estimated on

Oxytetracycline glucose yeast agar ( 5 days at 25 @c). The results of these counts provided estimates

of the level of dosage and the level of survivors per l-1

of atmosphere before and after treatment.

Results ;

Tables 5 and 6 below provides the data obtained in this trial for instances of the device operating with

either the electrostatic or H.E.P.A. filter in place.

Table 5

Single pass efficiency for Aspergillus Niger (mixed Hyphae and spores)employing Electrostatic filtration and 0

3 dosing

Challenge level cfu/l

-1/air pre in take

Recovery level cfu/l

-1/air post

filter

Percentage Kill

8.3E+05 7.6E+04 90.807

4.2E+05 2.0E+03 99.524

6.1E+05 4.1E+03 99.328

7.3E+05 9.2E+03 98.740

7.2E+05 6.2E+03 99.139

7.4E+05 7.1E+03 99.041

8.2E+05 8.4E+03 98.976

6.3E+05 9.2E+03 98.540

Mean 98.012

Table 6

Single pass efficiency for Aspergillus Niger (mixed Hyphae and spores)employing H.E.P.A. filtration and 0

3 dosing

Challenge level cfu/l

-1/air pre in take

Recovery level cfu/l

-1/air post

filter

Percentage Kill

5.5E+05 8.0E+01 99.985

6.1E+05 9.0E+01 99.985

2.8E+05 3.0E+01 99.989

6.1E+05 9.0E+01 99.985

6.3E+05 8.0E+01 99.987

5.2E+05 8.0E+01 99.985

6.3E+05 1.1E+02 99.983

5.8E+05 5.0E+01 99.991

Mean 99.986

Trial 3 ; Sensory appreciation ;

Outline : A sensory evaluation was conducted each day during operation of the device in the

microbiological waste processing facility. This involved subjective scoring by four people according to

the Key given with Table 7, below. Evaluations were made for each type of filter and with the Ozone

generator operating.

Table 7

Sensory appreciation scores obtained during operation of

the Quest Device with either Electrostatic filtration or H.E.P.A.

Day Electrostatic H.E.P.A.

0 1 1

1 3 2

2 6 2

3 6 3

4 6 2

5 6 3

6 6 2

7 6 3

Key to scores

1 Unpleasant

2 Change perceived but unpleasant

3 Improvement

4 Acceptable but some odour detected

5 Acceptable environment

6 Markedly improved odour free

Conclusions ;

Firstly considering the performance of the device in the Microbiological waste room From the data

given in tables 1-4 it is possible to conclude that the test environment under conditions of no treatment

did exhibit elevated levels of airborne microbial contamination. In the same tables it is observed that

irrespective of the filter type employed with device, measurable reduction of airborne levels of Gram

negative bacteria was achieved.

On a continuos use basis with active replacement of micro-organisms into the environment, operation

with Electrostatic filtration gave an average of 84 % reduction of gram negative bacteria (Ox +ve and

-ve). This amounts to a continuos overall reduction of between 1 and 2 log cycles. By comparison the

unit gave only 28 % when operated with H.E.P.A. filtration.

In theory H.E.P.A. filtration should provide greater efficiency with respect to microbial removal but

under the trial conditions we calculated that with this form of filtration in place the device was capable

of only 2.7 room changes per hour. It is apparent this was an insufficient flow rate to achieve high

levels of reduction in an environment to which micro-organisms are constantly being added.

In the case of operation with Electrostatic filtration we obtained 7.1 room changes per hour , a factor

which produced a much higher degree of impingement on the levels of airborne gram negative

bacteria.

It is interesting to note that both forms of filtration gave very high kill efficiencies during the single

pass trials with Aspergillus niger. In this case H.E.P.A. in combination with Ozonation gave 99.986

reduction of challenge which is close to theoretical performance. On the other hand Electrostatic

filtration in combination with ozonation gave 98.012 reduction of challenge.

______________________________________________________________________

Over all our data favours the combination of Ozonation with electrostatic filtration. This

configuration affords high flow rate with very high levels of kill in an environment where

recontamination of sanitised air is a continuos phenomena. By comparison with other commercial

units the kill rate in the waste room environment may be considered very significant. Additionally our

sensory trials indicate this conformation improves the human perception of the space in which the

device is operating.

Laboratories details and points of contact ;

CEO MR R D O.Connor

Tech Manager Mrs W Ingham

Microsearch Laboratories Ltd

Units 3-7 Scotts Trading Complex

Mytholmroyd

Halifax

West Yorkshire

England

HX7 5LH

Phone + 44 (0) 1422 885087 Fax +44 (0) 1422 883721

Email [email protected]

Interim report of an ongoing study into the efficiency of the

Airmanager (P8) Atmospheric Processing device in the

removal of Tobacco Smoke Analytes in a Public House Pool

room

Introduction

A study has been commissioned to determine the effectiveness of the Airmanager P8

atmospheric processing device in the removal of tobacco smoke analytes in a public

house pool room. This report details our preliminary findings in a single test

environment.

The Airmanager P8 atmospheric processing device produces improvement in the

quality of air by the oxidation of organic compounds and harmful micro-organisms

in the presence of high contained levels of Ozone. In this case Ozone is produced by

closed coupled field technology resulting in a unique highly oxidative environment

which produces no release of 03 to the environment. Additionally the output from the

Airmanager device is further purified after passing through a state of the art

electrostet filter assembly.

In this report we have examined the efficiency of the device in reduction of eight

types of tobacco related toxic substances in the test environment. These substances

primarily occur in the atmosphere due to combustion of tobacco and the associated

exhalation of smoke from combusted tobacco. A list of the analytes determined is

given in table 2 below.

The test environment consisted of a Public house pool room with a volume of 84 m3

into which an Airmanager P8 unit was installed. During operation the Airmanager

device, per specification, was predicted to change and process the environment within

this room at a rate 9 times per hour.

Common practice prior to the trial was to evacuated the atmosphere by forced and

passive ventilation. These systems of air purification were considered unsatisfactory

by the Landlord especially during the winter, due to the requirement to compensate

for massive heat loss.

Trial outline :

After installation of the Airmanager P8 device, air sampling was conducted in the

pool room for seven days, between the hours of 8.00 pm and 9.00 pm at a rate of 5

m3

per hour, without the Airmanager device in operation. This provided background

control data for all analytes. A further set of control data was obtained at 5.0 pm

which represents a point after normal ventilation and when the room is not used for

pool or smoking. The data relating to this point may be considered base level for all

analytes.

During the subsequent seven days the sampling procedure was repeated with the

Airmanager device in operation, with the goal of determining the efficiency of

atmospheric clean up.

During the trial an estimate was made of the daily cigarette consumption during the

sampling interval.

Sampling was conducted by the use of a vacuum device with collection of sampled

atmosphere in either Phosphate Buffer or an Acetonitrile : Methanol phase.

Analytes were determined quantitatively employing the following analytical

techniques : Gas Liquid Chromatography, HPLC diode array and Differential pulse

polarography.

Results ;

Table 1 below describes the pattern of cigarette consumption recorded for the test

environment during the sampling periods.

Table 2 describes the mean levels of analytes recorded during the control period and

during the period of sampling when the Airmanager P8 device was activated. This

table also describes the contribution to air quality attributable to the Airmanager P8

device in terms of percentage reduction of airborne toxic substances. Comparative

levels of each analyte for the both sampling periods are provided in graphical form.

Table 1

Mean cigarette consumption in a Public House pool room between

Between 8.00 PM and 9.00 PM

Day Cigarette consumption per

hour

Monday 5

Tuesday 11

Wednesday 7

Thursday 9

Friday 19

Saturday 23

Sunday 16

Mean 13

Table 2

Mean level of Tobacco smoke analytes in the atmosphere in a Public house pool room

for a seven day period with and without the Airmanager unit in operation

ANALTYE UNIT Mean Environmental level 5 PM No

treatment

Mean Environmental level 9 PM No

treatment

Mean Environmental level 9 PM with air treatment

Mean Environmental

reduction of Analyte due to

treatment

Device off Device off Device on

Carbon monoxide Mg/m3

0.82 7.1 0.4 94.4

3-Ethenylpyridine Mg/m3

0.17 37.6 0.4 98.9

Formaldehyde Mg/m3

0.33 84.2 0.2 99.8

Acetaldehyde Mg/m3

0.01 196.3 0.4 99.8

Ammonia Mg/m3

0.01 103.5 0.8 99.2

Nicotine Mg/m3

0.96 61.4 1.06 98.3

Total Phenolics Mg/m3

0.11 12.7 0.2 98.4

Total cresols mg/m3

0.06 3.8 0.08 97.9

0

50

100

150

200

mg

/m3

Atm

os

ph

ere

Mean levels of atmospheric tobacco smoke residue with

and with out the Airmanger unit in operation

Analyte Levels No

treatment

7.1 37.6 84.2 196.3 103.5 61.4 12.7 3.8

Analyte Levels with

Treatment

0.4 0.4 0.2 0.4 0.8 1.06 0.2 0.08

1 2 3 4 5 6 7 8

Conclusions & Discussion ;

There should be no doubt that the test environment represented a significant

challenge in terms of the levels of airborne tobacco related contaminants. Peak

usage of cigarettes was recorded at 23 per hour ( mean 13 ) in the test environment.

In addition both the Landlord and several of his staff anecdotally considered the

environment to be excessively ‘smoky’.

Our test data demonstrates that activation of Airmanager device produced highly

significant reduction in all levels of tobacco smoke analytes with overall analyte

clearance rates over the range 97 .9 to 99.8 %. The level of reduction is such that the

residue levels during device operation are not significantly different from background

level during periods when the room was in disuse. Considering our findings and that

there was virtually constant replacement of the analytes to the atmosphere, it is our

opinion that Airmanager P8 device has performed in a highly efficient manner in the

removal of toxic tobacco smoke contaminants

R.D.O’Connor B.Sc. Ci.Biol., M.R.I.P.H.H.

Trevor Smith B.Sc.

FINAL REPORT

Assessment of ozone leakage from an

air filtration unit

FOR

David Hallam

Quest International (UK) Limited

Unit 8F, Kayley Industrial Estate

Ashton-under-Lyne

Lancashire

OL7 0AU

Written by

Dr. Alexis J. Holden BSc PhD CChem

MRSC

Senior Lecturer, Analytical Science


Faculty of Science

Preston

PR12HE

Tel No. 01772 893521

Fax No. 01772 892903

Email: [email protected]

2 June 2003

1. Instructions from customer

The company, Quest International Limited, supplied to UCLAN, 1 AirManager

Air Filtration Unit (AM4). The company required tests to be undertaken which

determined if ozone was leaking from the air filtration system when it was

operational.

2. Tests performed

The leakage of ozone was measured when the air filtration system was operated in

4 different modes: (i) filter in and korona on; (ii) filter out and korona on; (iii)

filters in and korona off, and (iv) filters out and korona off.

The ozone levels were measured at 0, 0.5 and 1.0 m from the emitting face of the

unit. The distance was measured using a metre rule and was checked at intervals

during the experiment by the operator. The experiment was performed by 2

operators, Dr. Alexis Holden and Mr. James Donnelly (Technician).

The experiment was performed on 19 June 2002 in a laboratory that was at a

temperature of 22 °C.

The ozone measurement was performed using Gastec detection tubes (No. 18L).

The 18L range provides a rapid, fully quantitative analysis of the concentration of

ozone in air with an accuracy of ± 25%. The manufacturer states that the

minimum detectable concentration as 0.01 ppm. The Gastec tubes were purchased

specifically for this work and were marked valid until May 2005. A Gastec multi-

stroke gas sampling pump was used in conjunction with the tubes.

The principle of the gas tube operation is described by equation 1 below.

2O3 + C16H10N2O2 → 2C8H5NO2 + 2O2 Eqn (1).

The ozone in air, once sucked up through the tube, bleaches the indigo

(C16H10N2O2, blue) to form isatin (C8H5NO2), which is white in colour.

For each position, i.e. 0, 0.5 and 1.0 m from the emitting surface, (at an

approximate angle of 90º) and each operational mode, a tube was placed in the

pump and held in position manually. The system was left to stabilize for 5 minutes

and then 10 pumps (equivalent to 1000 cm3

volume) were drawn on the hand

pump. Each pump lasted an average of 30 seconds. The measurement for each

combination of position and operational mode was repeated five times.

3. Results

The individual results for each tube are shown in Table 1.

Table 1. Individual raw results (ppm) for the Gastec tubes.

Running

mode

Orde

r1

Replicate results

(ppm)

Mean Actual

value2

Operator

1 2 3 4 5 (ppm) (ppm)

Filter in;

Korona on

0 m 4th

0.1 0.1 0.1 0.1 0.1 0.1 0.05 J. Donnelly

0.5 m 5th

0 0 0 0 0 0 0 J. Donnelly

1.0 m 6th

0 0 0 0 0 0 0 J. Donnelly

Filter out;

Korona on

0 m 3rd

<0.05 <0.05 <0.05 <0.05 <0.05 <0.05 <0.025 A. Holden

0.5 m 7th

0 0 0 0 0 0 0 J. Donnelly

1.0 m 8th

0 0 0 0 0 0 0 J. Donnelly

Filter in;

Korona off

0 m 1st 0 0 0 0 0 0 0 J. Donnelly

0.5 m 11th 0 0 0 0 0 0 0 J. Donnelly

1.0 m 12th 0 0 0 0 0 0 0 J. Donnelly

Filter out;

Korona off

0 m 2nd

0 0 0 0 0 0 0 J. Donnelly

0.5 m 9th

0 0 0 0 0 0 0 J. Donnelly

1.0 m 10th 0 0 0 0 0 0 0 J. Donnelly

1this shows the order in which the replicates where run.

2As 10 pumps were used, the values read from the tubes were halved as per the

manufacturers instructions.

4. Discussion and conclusions

The readings were very small such that the highest readings only coloured the first

graduation on the Gastec tube. The highest reading was recorded when the tube

was placed at the emitting surface and the filter was in and the korona was on. The

next highest reading was recorded with the korona on, but the filter out. All other

positions and operational combinations produced no change of colour on the

Gastec tube indicating the levels of ozone, if present, were less than 0.01 ppm.

The average gap in the Gastec tube through which the air is drawn was 1 mm. The

analysis system used is known as active sampling. Five replicate tubes were used

for each combination to help account for the potential variability in the positioning

of the Gastec tube within the flow of air exiting from the air filtration system.

5. Recommendations

The experiment undertaken used active sampling to measure the ozone levels

emitting from the surface of the AirManager Air Filtration Unit. There may be

merit in repeating the experiment with the operational modes of (i) korona on and

filter in and (ii) korona on and out, using passive sampling. Passive sampling does

not use a pump and allows the air to naturally interact with the contents of the

Gastec tube. This would involve placing a number of passive samplers around the

vicinity of the Unit whilst it was in operation. The running time used should be

typical of situations where the Unit would be functioning. This experiment may

provide a better representation of the ozone levels emitted during a normal

working phase of the AirManager Air Filtration Unit.

………………………………………….

Dr. Alexis J. Holden

………………………………………….

Date

FINAL REPORT

Assessment of ozone leakage from an

air filtration unit: passive sampling

FOR

David Hallam

Quest International (UK) Limited

Unit 8F

Kayley Industrial Estate

Richmond Street

Ashton-u-Lyne

Lancashire

OL7 0AU

Written by

Dr. Alexis J. Holden BSc PhD

CChem MRSC

Senior Lecturer, Analytical Science


Faculty of Science

Preston

PR1 2HE

Tel. No: 01772 893521

Fax No: 01772 892903

Email: [email protected]

13th

January 2004

Contents Page

1 Instructions from customer 2

2 Test performed 2

3 Results 3

4 Discussion and conclusions 4

Appendix 1: Principle of operation of the passive sampling cards 5 Appendix 2: Details of the sensitivities of each passive sampling card

used. 6

Appendix 3a: Indication of the different positions of the passive sampling

cards. 7

Appendix 3b: Indicative plan of the different ceiling positions of the

passive sampling cards. 8

Appendix 3c: Indicative plan of the different positions of the passive

sampling cards. 9

1. Instructions from customer

The company, Quest International Limited, supplied to UCLan, 1 AirManagerAir

Filtration Unit (AM4). The company required tests to be undertaken which

determined if a significant concentration of ozone was leaking from the air

filtration system when it was in operation over an 8 hour period. The analysis was

to be passively sampled.

2. Tests performed

A room of approximately 36.75m3 (3.5m (h) x 3.5m x 3.0m) was selected. It had a

small window on one wall and a normal sized door. One wall (containing the

window) was an external wall the other 3 walls were not exposed to the outside.

The room was dark with fluorescent lighting and received minimal natural light.

To measure the ozone levels passively a number of different sampling cards were

used:

(i) ChromAir ozone cards;

(ii) ChromAir nitrogen cards;

(iii) SafeAir ozone cards;

(iv) SafeAir nitrogen dioxide cards.

The cards were purchased from AFC International Inc. (USA). Nitrogen dioxide is

a potential positive interferent beyond 0.3 ppm with both of the ozone sampling

cards. The experiment monitored this substance alongside the ozone levels. The

principle of operation of the cards is given in Appendix 1.

The experiment was performed on the 4th and 5th

November 2003. The

temperature of the room at an average of 19 ºC.

A sample of each card was placed at random positions within the room. Cards

were placed on the floor, walls and suspended from the ceiling. An indication of

the positions is given in Appendix 2.

Two experiments were conducted, the first, the control experiment where the

cards were monitored for 8 hours whilst the air filtration system was switched off.

In the second experiment the air filtration system was switched on with the corona

on and filter in. The sampler readings were recorded every 15 minutes for the first

hour and then read after a further 7 hours for both experiments.

Originally the experiment was designed to record any change in ozone level

detected by the card every hour. This was eventually rejected as it would have

meant disturbing the air flow (by opening and closing the door) when the recorder

entered the room each hour.

3. Results

An example of a SafeAir ozone qualitative card for a control analysis and a result

from the ‘system on’ experiment is shown in Figure 1.

Control experiment:

(i) All ChromAir ozone cards gave a reading of 0.08 ppm/ hr*

- therefore for 8 hour sampling, 0.08/8 = 0.01

ppm

(ii) No change observed with the SafeAir ozone cards

(iii) No change observed in any of the nitrogen dioxide cards.

Figure 1. Examples from the ozone detection for the (a) blank and (b) ‘system on’

experiments.

* This is the lowest recordable concentration available with the ChromAir ozone

cards; this is the background reading of the cards.

‘System on’ experiment:

(i) All ChromAir ozone cards gave a reading of 0.40 ppm/ 8hr

- therefore for 8 hour sampling, 0.40/8 = 0.05

ppm

(ii) All SafeAir ozone cards showed a qualitative change indicating the

presence of ozone.

(iii) No change observed in any of the nitrogen dioxide cards.

Overall levels of ozone = [‘System on’ experiment] – [Control experiment]

= [0.05 ppm] – [0.01 ppm]

= 0.04 ppm

Therefore, the time weighted average for the concentration emitted over an 8

hour period is 0.04 ppm (40 ppb).

4. Discussion and conclusions

The HSE occupational exposure limits (OEL) for ozone over an 8 hour period is

0.2 ppm (200 ppb). This experiment produced a recordable value of 0.04 ppm (40

ppb) over an 8 hour period. HSE also states a limit of exposure for 15 minutes of

0.4 ppm (400 ppb), the experiment conducted for this reported produced no

observable changes in the passive samplers within the first hour of the experiment.

It should be noted that the actual observation of any change in colour on the

sampling cards is quite subjective. The assessment of the recorded value is added

by a colour comparator chart but this was extremely rudimentary in accuracy. All

readings were observed by 1 person (Ms June Gardner and the results of a

proportion of the samples confirmed by Dr. Alexis Holden).

……………………………………………………

Dr. Alexis J. Holden

……………………………………………………

Date

Appendix 1: Principle of operation of the passive sampling cards

ChromAir Ozone passive samplers (Part #380010-10)

The ChromAir passive monitor is a patented direct read autogenic exposimeter. The

device is constructed from six cells attached on one side to a flat indicator layer and

on the other side to a series of different diffusive resistances. Ozone gas diffuses to

the cells through the different diffusive resistances and reacts with the indicator layer,

producing colour change from blue to light blue and finally to white upon high

exposure. The colour produced on the indicator layer is a direct measure of the

exposure dose. Visual colour comparison is achieved by observing the formation of

the light blue threshold colour on the individual cell and reading the corresponding

exposure dose.

SafeAir ozone passive samplers (Part#382004)

The SafeAir ozone badge is a monitoring system designed to indicate the presence of

ozone at concentrations below the permissible exposure limit. The SafeAir ozone

badge detects the presence of ozone by forming a colour change in the shape of an

exclamation mark inside the triangle. This indication is produced by a colour forming

reaction which occurs when ozone reacts with a flat indicator layer. The colour

change is from blue to a lighter blue.

ChromAir Nitrogen Dioxide passive samplers (Part #380006)

The ChromAir passive monitor is a patented direct read autogenic exposimeter. The

device is constructed from six cells attached on one side to a flat indicator layer and

on the other side to a series of different diffusive resistances. Nitrogen dioxide gas

diffuses to the cells through the different diffusive resistances and reacts with the

indicator layer, producing colour change from yellow to beige to brown. The colour

produced on the indicator layer is a direct measure of the exposure dose. Visual

colour comparison is achieved by observing the formation of the beige threshold

colour on the individual cell and reading the corresponding exposure dose.

SafeAir nitrogen dioxide passive samplers (Part#382013)

The SafeAir nitrogen dioxide badge is a monitoring system designed to indicate the

presence of nitrogen dioxide at concentrations below the permissible exposure limit.

The SafeAir nitrogen dioxide badge detects the presence of nitrogen dioxide by

forming a colour change in the shape of an exclamation mark inside the triangle. This

indication is produced by a colour forming reaction which occurs when nitrogen

dioxide reacts with a flat indicator layer. The colour change is from white to pale

yellow.

Appendix 2: Details of the sensitivities of each passive sampling card used.

ChromAir system card

Ozone cards Nitrogen dioxide

Physical specifications

Dimensions 10.5 cm x 5.5 cm x 0.25

cm

10.5 cm x 5.5 cm x

0.25 cm

Weight 11 g 11 g

Refrigerated shelf life 1 year 1 year

Colour change Blue to white Yellow to beige to

brown

Sampling parameters

Exposure range for:

Badge 0.08 – 1.6 ppm.hr 0.5 - > 13 ppm.hr

Badge with colour comparator 0.08 – 2.6 ppm.hr 0.35 – 40 ppm.hr

Max. recommended sampling

time

10 hours 2 days

Min. recommended sampling

time

5 minutes 15 minutes

Temperature range 16 – 30 ºC 10 – 40 ºC

SafeAir system card

Ozone cards Nitrogen dioxide

Physical specifications

Dimensions 7.4 cm x 4.1 cm x 0.1

cm

7.4 cm x 4.1 cm x 0.1

cm

Weight 1.5 g 1.5 g

Refrigerated shelf life 1 year 1 year

Colour change Blue to white Yellow to brown

Sampling parameters

Exposure level 0.05 ppm.hr 1.0 ppm.hr

Minimum detectable limit (8

hours)

0.006 ppm 0.125 ppm

Max. recommended sampling

time

2 days 10 hours

Min. recommended sampling

time

15 minutes 15 minutes

Temperature range 16 – 33 ºC 15 – 40 ºC

Appendix 3a: Indication of the different positions of the passive sampling cards.

Label Distance from filtration system

(via floor)

Distance from filtration system

(via air)

F1 4 ft 2 in. -

F2 2 ft 11 in. -

F3 2 ft 6 in. -

F4 1 ft 10 in. -

F5 2 ft 4 in. -

F6 3 ft 3 in. -

F7 4 ft 0 in. -

F8 3 ft 2 in. -

F9 5 ft 0 in. -

F10 4 ft 4 in. -

F11 2 ft 1 in. -

F12 4 ft 9 in. -

F13 3 ft 7 in. -

F14 2 ft 0 in. -

F15 2 ft 6 in. -

F16 3 ft 7 in. -

F17 4 ft 4 in. -

F18 2 ft 4 in. -

F19 2 ft 7 in. -

W1 6 ft 2 in. 8 ft 3in.

W2 3 ft 7 in. 1 ft 2 in

W3 5 ft 10 in. 7 ft 11 in.

W4 4 ft 4 in. 7 ft 9 in.

W5 6 ft 7 in. 9 ft 0 in.

W6 5 ft 10 in. 8 ft 4 in.

W7 3 ft 9 in. 6 ft 7 in.

W8 5 ft 0 in. 6 ft 9 in.

W9 1 ft 10 in. 6 ft 4 in.

W10 7 ft 9 in. 10 ft 0 in.

C1 4 ft 5 in. 6 ft 4 in.

C2 6 ft 5 in. 6 ft 4 in.

C3 4 ft 0in. 5 ft 9 in.

C5 5 ft 0 in. 4 ft 8 in.

C6 6 ft 6 in. 6 ft 7in.

C7 6 ft 8in. 5 ft 0in.

C8 7 ft 4in. 6 ft 9 in.

C9 7 ft 7 in. 7 ft 10in.

C10 7 ft 4 in. 8 ft 2 in.

Appendix 3b: Indicative plan of the different ceiling positions of the passive

sampling cards.

DOORDOOR

WINDOW

AIR

FILTRATION

SYSTEM

C9 C3

C7

C6

C2

C1

C5

C10

Appendix 3c: Indicative plan of the different positions of the passive sampling

cards.

WINDOW

AIR

FILTRATION

SYSTEM

W5

W4

F12

W9

F13

F10

F9

W3

F11

F14

F15

F16 W6

F17

F18

F19 W7

F8

W2

F7

F6

W1 W8

W10

F1

F2

F4

F3

F5

DOOR

of 16 Hygiene:\2005\contract\Airmanager/FH83479/1

CCFRA Technology Limited

Chipping Campden

Gloucestershire

GL55 6LD, UK

Tel: +44 (0)1386 842000

Fax: +44 (0)1386 842100

www.campden.co.uk

CAMPDEN & CHORLEYWOOD FOOD RESEARCH ASSOCIATION

CHIPPING CAMPDEN, GLOS. GL55 6LD.

INVESTIGATION OF EFFECTIVENESS OF AIR MANAGER UNIT

CONFIDENTIAL TO: David Hallam

Quest International Air Manager Division

Unit 8F

Kayley Industrial Estate

Richmond Street

Ashton-under-Lyne

Greater Manchester

OL7 0AU

REPORT NO. FH83479/1

AUTHORS: Dr. K. L. Brown,

Chloe Stripp

May 2005

Report Approved By : Report Checked By :

Name : :

Information emanating from this company is given after the exercise of all reasonable care and skill in its compilation, preparation

and issue, but is provided without liability in its application and use. Campden & Chorleywood Food Research Association.

Company limited by guarantee. Registered No. 510618 England

CCFRA Technology Limited. Registered No. 3836922 England

CCFRA Group Services. Registered No. 3841905 England

Registered Office: Chipping Campden, Glos. GL55 6LD

Information emanating from the CCFRA Group is given after the exercise

of all reasonable care and skill in its compilation, preparation and issue.

but is provided without liability in its application and use.

ISO 9001: 2000

Certified


Introduction and background information

CCFRA were approached by David Hallam of Quest International to evaluate the

effectiveness of an Air Manager unit against airborne challenge tests in a controlled

environmental room. Initial tests were done using BVM190 units in a room of

volume 39.6m3. Later experiments were done using an AM4 unit. The test organisms

were chosen either because they were typical environmental contaminants or because

they were standard test strains.

Summary of experiments

Units tested: BVM190. This unit can treat 165m3/h.

AM4. This unit can treat 190m3/h

Room volume: 39.6m3 (3.5m wide, 4.1m long and 3m high minus airlock 1m wide,

1.14m long and 3 m high). Four fans (12x12cm) positioned on the floor of the room

were used to ensure the aerosols were mixed adequately in the air. Each fan is rated

at a nominal 30l/s throughput.

Parameters monitored: Air temperature and relative humidity.

Test organisms:

Pseudomonas aeruginosa (NCIMB 10421) (Test strain for disinfectant testing)

Staphylococcus aureus (NCIMB 9518) (Test strain for disinfectant testing)

Penicillium chrysogenum (CABI 024314)

Bacillus subtilis var globigii B17 (culture from Nottingham University) (Used as a

test organism for packaging and air sterilisation)

Neurospora (Chrysonilia) sitophila (CABI 021944) (At request of client)

Preparation of spore suspensions and cultures:

Bacillus subtilis var. globigii spores

A stock culture of Bacillus subtilis var. globigii was inoculated into Nutrient Broth

(Oxoid CM1) (NB) and incubated overnight at 30°C in a shaking incubator. Nutrient

Agar (Oxoid CM3) (NA) plates were then seeded with the culture and incubated agar

side down for 6 days at 30°C. The cultures were checked microscopically to ensure

that spores had been produced. The spores were removed using a metal scraper into

sterile distilled water. The initial count was determined to be 5.7 x 109/ml. The spore

crop was diluted to give a concentration of approx. 107/ml.


Penicillium chrysogenum and Neurospora (Chrysonilia) sitophila spores

Penicillium chrysogenum and Neurospora (Chrysonilia) sitophila spores from a

previous spore crop were spread onto the surface of pre-poured 150mm diameter Petri

dishes containing Malt Extract Agar (Oxoid CM59). These were incubated for 2 days

at room temperature until the fungal growth had covered the surface of the plates.

The temperature was then increased to 25oC for 3 days to induce spore production.

The spores were scraped from the surface of the agar in a suspension of 0.1% Tween

80. The resulting suspension was filtered through sterile glass wool, spun down twice

at 2000rpm for 20 min and resuspended in Maximum Recovery Diluent (MRD, Oxoid

CM733). The concentration of spores was estimated using a Haemocytometer.

Recovery medium for experiments using mould was Malt Extract Agar (Oxoid

CM59).

Pseudomonas aeruginosa and Staphylococcus aureus

Ps. aeruginosa and S. aureus were grown overnight ready for trials the next day on

TSA (Oxoid CM131) at 30 and 37oC respectively. Growth was removed and

resuspended in Maximum Recovery Diluent (MRD, Oxoid CM733). The resulting

suspension contained approximately 109 cells/ml (determined using a

spectrophotometer). The concentration was then adjusted with MRD to give

approximately 107 cells/ml. The recovery medium for S. aureus: Baird Parker Agar

(Oxoid CM275) plus supplement (Oxoid SR54). The recovery medium for Ps.

aeruginosa: Pseudomonas Agar base (Oxoid CM559).

Spraying procedure for test organisms:

A Collison nebuliser was used to create an aerosol at approximately 1m above the

floor at one side of the room. The nebuliser releases approximately 0.2ml/min

aerosol. Aerosol times were adjusted in line with the concentration of the bacteria in

the suspension to give a starting level of approximately 105 – 10

6/m

3 in the room air.

This represents very heavily contaminated air and the aim was also to have countable

numbers in the air samplers.

Air sampling:

The 2 sampling ports in one wall of the room were connected to 2 Oxoid MAQS air

samplers. A Mattson-Garvin air sampler that sampled air over one hour continuously

was connected to the room and used to give a picture of the airborne counts over the

time frame of the experiment.

Theory:

The room is 39.6m3 and the rate of throughput in the BVM190 is 165m

3/h.

Let V1 = throughput of unit

Let VT = total room volume

Let Cin = Concentration of bacteria/m3 entering unit at any point in time

Let Cout = Concentration of bacteria/m3 leaving the unit

Let CT = Concentration at a point in time


Reduction in concentration of bacteria, p = (Cin-Cout)/Cin

Also dCt/dt = -(V1/VT).(p.CT)

For first order reaction, Ct = C0e-kt

Where C0 = starting concentration and k = -(V1/VT).(p)

Plotting log CT against time (t) should give a straight line with slope –(V1/VT).p/2.303

Assuming 100% efficiency of the unit in removing airborne bacteria, p becomes equal

to 1. In approximately 15 minutes the unit has processed a volume of air equivalent to

the room volume so V1/VT after 15 minutes is approximately 1. Dividing 15 by 2.303

gives approximately 7. Therefore we would expect to see one log reduction in

airborne count in around 7 minutes (assuming 100% efficiency). The AM4 unit

should give 1 log reduction in approximately 5.4 min using the same calculations.

The control run with the unit switched off was estimated to take at least 4 hours based

on previous work. A ranging trial using the spores of B. globigii was done first to

determine the sampling times for subsequent experiments.

Experimental protocol:

Suspensions of B. globigii or mould spores or suspensions of overnight bacterial

cultures were produced as appropriate. The Collison nebuliser was filled with the

suspension (one organism tested at a time).

The room circulation fans and the Quest unit were switched on.

The nebuliser was operated for a fixed time interval to create the aerosol.

A continuous sample was taken using a Mattson Garvin air sampler and discrete

samples were taken every 15 min using two Oxoid MAQS samplers (100 litre or 200

litre sample size).

At the end of sampling, any remaining airborne micro-organisms were flushed out

using the room extract system and the floor was mopped with disinfectant.

Each trial was repeated with the Air Manager unit switched off.

The airborne counts were compared with and without the Air Manager unit operating

to estimate the performance of the unit.

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Figure 1 Layout of test room for experiments 1 and 2

Figure 2 Layout of test room for experiments 3 to 19

Key:

Neb = Collison nebuliser used to produce aerosol positioned approximately 1m above the floor.

Fans were small 15W fans (12x12cm) moving air at approximately 3m/s and positioned on the floor.

MAQS samplers sampled through 2 ports in the wall.

Arrows indicate direction of air flow. In layout 2, the three small fans were pointing upwards to

circulate the air.

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Results

Experiments 1 – 5 were done using the first BVM190 unit that can treat up to

165m3/h. Results from these first trials using spores of Bacillus subtilis var globigii

showed little difference with unit switched on or off (Figures 3 and 4). Because there

was no visible means of determining whether this unit was working properly or not, a

new unit that had been tested for correct functioning was supplied. This second

BVM190 unit was used for experiments 6 to 9 and was only marginally better than the

first (Figures 5 and 6). It was then decided to use the larger capacity AM4 unit that

can treat 190m3/h. This was used for experiments 10 to 19

Results with the AM4 unit for P. chrysogenum spores are shown in Figures 7 and 8.

After 4 hours there was approximately a 3-log difference in airborne count between

experiments with the unit on versus off. There was approximately 1 log difference

after approximately 112 min.

Results for B. subtilis spores showed approximately 1 log difference after 4 hours

with the AM4 unit compared to approximately ¾ of a log reduction with the BVM190

unit. (Figures 9 and 6 respectively).

Staphylococcus aureus results (Figure 10) showed approximately 1 log difference

after 65 minutes. This is also shown in the photograph (Figure 11).

Ps aeruginosa gave approximately 1¾-log difference after approximately 80 min.

(Figure 12).

Neurospora (Chrysonilia) sitophila colonies were very difficult to count because the

organism grows rapidly, covering the Petri dish and even growing out of the dish very

quickly. (Figure 16). Results were therefore expressed as presence or absence of

growth (Tables 3 and 4). The airborne spores had been removed by the AM4 unit

within 90 min as shown by the MAQS samples and between 1 and 2 hours as shown

by the Mattson results (Figures 13 and 14). By comparison, with the AM4 switched

off, airborne spores were still detectable between 3 and 4 hours. Figure 15 shows

MAQS sample plates after 3h and 3h 15min with the unit switched off. This was the

approximate time when the spores had settled naturally from the air. (One MAQS

plate was positive after 3h 30min).


Figure 3 Results using BVM190 (Ser No 3682)

B. subtilis spores: Experiment 1 (unit on) and experiment 2 (unit off) MAQS results

0

0.2

0.4

0.6

0.8

1

1.2

0 10 20 30 40 50 60 70

Time (min)

Lo

g N

/ lo

g N

o p

er

m3

mean on

mean off

Figure 4 Mattson results for Bacillus subtilis from 1 – 2 hours during

experiments 1 and 2. Plate on the left shows results with Airmanager BVM190

off and on the right with Airmanager BVM190 on.



B. subtilis spores: Experiment 8 (unit on) and experiment 9 (unit off) - MAQS results

-0.20

0.00

0.20

0.40

0.60

0.80

1.00

1.20

0 50 100 150 200 250 300

Time (min)

Lo

g N

/ lo

g N

o p

er

m3

mean off

mean on


B. subtilis spores: Experiment 8 (unit on) and experiment 9 (unit off) - Mattson results

0

0.5

1

1.5

2

2.5

3

3.5

4

0 50 100 150 200 250

Time (min)

Lo

g c

ou

nt

ov

er

5 m

in

unit on

unit off


Figure 7 Results using AM4 (Ser No 3656)

P. chrysogenum spores: Experiment 10 (unit on) and experiment 11 (unit off) - Mattson results

-1

-0.5

0

0.5

1

1.5

2

2.5

3

3.5

0 50 100 150 200 250

Time (Min)

Lo

g c

ou

nt

over

5 m

in

unit on

unit off

Figure 8 Mattson results for Penicillium chrysogenum from 1 – 2 hours during

experiments 10 and 11. Plate on the left shows results with Airmanager AM4 off

and on the right with Airmanager AM4 on.



B. subtilis spores: Experiment 12 (unit on) and experiment 13 (unit off) - Mattson results

0

0.5

1

1.5

2

2.5

3

3.5

4

0 50 100 150 200 250

Time (min)

Lo

g C

ou

nt

ov

er

5 m

in

Unit On

Unit Off


Staph aureus: Experiment 14 (unit on) and experiment 15 (unit off) - Mattson results

0

0.5

1

1.5

2

2.5

3

3.5

4

0 50 100 150 200 250

Time (min)

Lo

g c

ou

nt

over

5 m

in

unit on

unit off


Figure 11 Mattson results for Staphylococcus aureus from 1 – 2 hours during

experiments 14 and 15. Plate on the left shows results with Air Manager AM4 on

and on the right with Airmanager AM4 off.


Ps aeruginosa: Experiment 16 (unit on) and experiment 17 (unit off) - Mattson results

-1

-0.5

0

0.5

1

1.5

2

2.5

3

3.5

4

0 50 100 150 200 250

Time (min)

Lo

g c

ou

nt

over

5 m

in

Unit on

Unit off


Table 2 Results from MAQS samplers (200 litre samples) for AM4 unit operating against

airborne Neurospora (Chrysonilia) sitophila spores

Time (min) Unit AM4 on Experiment 18 Unit AM4 off Experiment 19

MAQS 1 MAQS 2 MAQS 1 MAQS 2

5 + + + +

15 + + + +

30 + + + +

45 + + + +

60 + + + +

75 - - + +

90 - + + +

105 - - + +

120 - - + +

135 - - + +

150 - - - +

165 - - + -

180 - - + +

195 - - - -

210 - - - -

225 - - - -

240 - - - -

Key: Since Neurospora colonies spread very rapidly over the plates it was not possible

to count individual colonies so results were expressed as:

(+) = growth over plate, (-) = no growth

Table 3 Results from Mattson sampler for AM4 unit operating against airborne

Neurospora (Chrysonilia) sitophila spores

Time period

(h)

Unit AM4 on. Experiment 18 Unit AM4 off. Experiment 19

0-1 + +

1-2 + +

2-3 - +

3-4 - +

Key: Since Neurospora colonies spread very rapidly over the plates it was not possible

to count individual colonies so results were expressed as:

(+) = growth over plate, (-) = no growth


Figure 13 Mattson results for Neurospora (Chrysonilia) sitophila from 0-1h on

the left and 1-2h on the right with AM4 unit on. Airborne Neurospora has been

removed between 1-2 h. (Experiment 18)

Figure 14 Mattson results for Neurospora (Chrysonilia) sitophila from 0-1h on

the left and 2-3h on the right with AM4 unit on. Airborne Neurospora has been

totally removed by 2h. (Experiment 18)


Figure 15 Results from MAQS plates for Neurospora (Chrysonilia)

sitophila with AM4 unit (experiment 19). Samples taken after 3h on

the left with unit off and after 3h 15m on the right with unit on.

Figure 16 Results from MAQS plates for Neurospora (Chrysonilia) sitophila with

AM4 unit off (experiment 19). Samples taken after 5 minutes showing how this

organism spreads over the whole of the agar surface and beyond the edge of the

plate.


Conclusions

The AM4 unit was effective in removing aerosols of the test organisms: Pseudomonas

aeruginosa (NCIMB 10421), Staphylococcus aureus (NCIMB 9518), Penicillium

chrysogenum (CABI 024314), Bacillus subtilis var globigii B17 (culture from

Nottingham University) and Neurospora (Chrysonilia) sitophila (CABI 021944).

Within the time frame of these experiments (up to 4 hours) log reductions achieved

were typically between 1 and 2 log reductions compared to results with the unit

switched off.


Mountainheath Services Ltd. Environmental Analysis & Consultancy

Analytical Report

Quest International (UK) Ltd Report No: N1487 Addendum

Unit 8F, Kayley Industrial Estate, Date Received: 12 August 2005

Richmond Street Date Tested: 17/08/05-09/09/05

Ashton Under Lyne Date Issued: 09 September 2005

OL7 0AU Page: 1 of 1

For the attention of: David Hallam (Director) By e-mail (original by post)

In order to better assess the efficiency of the filter at removing oil pyrolysis products, results

were calculated for a wider range of organic compounds as well as for total organics removal.

These are presented in the table below.

Laboratory reference 94436 94434 94433 94432

Client referenceConc. µg/m

3

no filter

Conc. µg/m3

3 passes

% removal

Conc. µg/m3

9 passes

% removal

Conc. µg/m3

ambient air

hexanal 140 4.8 99 1.7 99 0.484-methyloctane 160 14 97 9.7 98 7.1

N,N-dimethylacetamide 13000 590 98 400 100 370phenol 730 120 98 45 100 87

n-dodecane 59 1.9 99 0.90 102 2.2dodecamethylcyclohexasiloxane 260 13 100 6.2 100 6.2

total organics 45000 960 99 760 100 760

They indicate a better performance than previously calculated from the N,N-

dimethylacetamide figures. The erroneous result was caused by a computer integrator error as

it was not able to cope with the very high absolute values involved, i.e.: they were out of

range. Results have been recalculated taking this into consideration. The results show a

consistent performance of 97% to 100% removal after three passes of the filter considering

the ambient air concentration as the base line.

The total ion current traces were re-examined in order to investigate the occurrence of

unchanged oil additives. This was achieved by constructing ion chromatograms of these

compounds using relevant mass fragments in their mass spectra. These compounds, i.e.:

tricresyl phosphate, N-phenyl-2-naphthalenamine, 1-naphthalenamine, 2-naphthalenamine

and 4-octyl-N-(4-octylphenyl)benzenamine, could not be detected at a concentration greater

than approximately 0.10µg/m3. This is not conclusive evidence that the compounds were not

present in the rig as they are relatively involatile and not therefore suitable for Tedlar bag

sampling. The results from the filter sampling would be more indicative of the absence of

these compounds as this might be expected to be a more appropriate method for their

recovery. The absence of any response in the traces obtained from the filter samples would

indicate their absence above a concentration of approximately 1.0 µg/m3.

Pamela M Howarth Sally Paynter Alex Waggott

Director Quality Manager Director

close coupled field accredited research results...penicillium chrysogenum, bacillus subtilis var...

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