Data Harvest 1157 User manual

© Copyright Data Harvest Group Ltd - All Rights Reserved - Freely photocopiable for use within the purchaser’s
establishment
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Table of contents
Introduction ...................................................................................................... 3
Pack Contents .................................................................................................... 5
Operational Overview ......................................................................................... 6
Connectivity ...................................................................................................... 8
Charging the Sensor ........................................................................................... 9
Firmware Updates ............................................................................................ 10
Usage Information ............................................................................................ 11
Practical Investigations ..................................................................................... 15
Sensor Specifications ........................................................................................ 17
Limited Warranty ............................................................................................. 18
Compliance ..................................................................................................... 19
Troubleshooting ............................................................................................... 20
Notices ............................................................................................................ 21
Contact Information .......................................................................................... 22
PDF Translations .............................................................................................. 23

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Introduction
Thank you for purchasing the Smart Wireless Spirometer. We pride ourselves on producing high
quality products that meet with the demands of the busy classroom environment. If you have any
problems using this sensor, please read this documentation in full before contacting the Data Harvest
support team.
The Smart wireless Spirometer is a differential pressure transducer that interfaces to a pair of flow
heads to measure air flow rate. The sensor works by measuring pressure drop across a reference flow
resistance. An embedded microprocessor in the Spirometer converts the pressure readings into air flow
rate.
The user can choose to see data from the sensor as flow, volume, corrected volume, breathing rate or
change in pressure.
Alternatively the air flow data can be converted to volume using a simple function in the software after
data collection.
The Spirometer is supplied with a nose clip, 4 flow heads (one attached and three for test subjects) and
a circular guard for the ‘fixed’ flow head (to prevent it being used).
A flow head contains an antibacterial and antiviral filter to lessen the possibility of cross contamination
between subjects. Two flow heads are attached to the Spirometer during use; one is kept fixed in place
and the other is the test subject’s flow head. To minimise the danger of cross contamination, the flow
head used by the test subject is only for their own use and should be regarded as a ‘disposable’ item.
Note: The air flow rate measurement is only valid if two flow heads are fitted to the Spirometer
during use.
Replacement packs of 10 flow heads (Product No. 3269) and 5 nose clips (Product No. 3264) are
available from Data Harvest. Contact sales for further information.

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Disclaimer
The Smart Wireless Spirometer is sold for the purpose of teaching and educational instruction. It is not
and has not been designed to be a diagnostic tool. The results are illustrative only; any information
gained from the use of this apparatus must not be used as the basis for any medical or clinical
diagnosis.
Read the instructions before use. Students should be supervised at all times.
Follow your local safety guidelines. It is the responsibility of the tutor to ensure
that individuals using this apparatus are healthy and have no history of
respiratory or cardiovascular problems. The students must be reassured about
the medical validity of the results. Respiratory tests can be challenging; limit the
number of tests in a session and take care that an individual is not overstressed
by the tests.
WE DO NOT RECOMMEND THE USE OF THIS SENSOR WITH INDIVIDUALS UNDER THE AGE
OF 10.
Overview
The Smart Wireless Spirometer is USB and Bluetooth compatible. Using Bluetooth, a sensor can
connect to mobile devices, tablets, laptops, and desktops.
The sensor has several ranges (flow (default), volume, adjusted volume, cyclic volume, breathing rate,
differential pressure). Any range can be selected on its own or selected alongside any other range.
The range required is set in the Devices icon of the EasySense2 software.
The Spirometer is used to measure changes in the volume of the inhaled and exhaled air. The total
volume of the lung can be calculated from various breathing processes and calculation of the
anatomical dead space.
The spirometer integrates the flow to produce volume (i.e. a flow of 1 l/s must produce 1 litre of volume
in one second and 2 litres of volume in 2 seconds etc.). Any value of the flow that differs from zero at
the start will become “integrated” into the volume and will be seen in the final data as a slope in the
data. A calibration function and Tare function are present to allow the no flow through of the Spirometer
become the zero base line to reduce this effect.
Additionally, the adjusted volume range uses mathematics to bring the data back to effective zero after
each breathing cycle.

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Pack Contents
This product is supplied with the following items:
· 1 x Smart Wireless Spirometer
· 1x Nose clips
· 4 x Flow heads
· Circular guard element
· 1 x USB cable

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Operational Overview
The diagram below shows the specific parts of the sensor. Read further to explore the functionality of
each part of the sensor.
1.Sensor End Cap
2.Status Indicator
3.On/Off Switch
4.USB Port
5.Unique ID Number
Sensor End Cap (1)
Most Smart Wireless Sensors feature an end cap that is specific to the requirements of the device's
internal sensor. The sensor's end cap is the direct interface between the device’s internal sensor and
your experiment.
The Status Indicators (2)
The sensor features a single status indicator that changes colour and flashes. See the table below for
further information.
Status Light Indicates
No light Sensor is Off. Short press the On/Off switch
Blue flashing Sensor is On and Bluetooth advertising
White flashing Charging via USB mains charger or USB port,
Sensor is On and Bluetooth advertising
Red, Green, Blue
Flashing Charging via USB mains charger or USB port, Sensor is Off

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Green flashing Communication with the EasySense2 app (via USB or
Bluetooth) has been established
Solid Green Fully charged
Orange flashing Recording data
Red flashing Battery is low
On/Off Switch (3)
The sensor's on/off switch allows you to turn the sensor on, off or perform a hard reset.
To switch the sensor off
· Press and hold down the On/Off switch until the white light shows, then release.
· If not communicating with the EasySense2 app, the sensor will turn off after a period of one hour of
inactivity.
Hard resetting the sensor
· If necessary, attach the sensor to power.
· Press and hold down the On/Off button for at least 8 seconds until the status LED gives a flash of
blue light, then release.
· If the sensor fails to respond, contact Product Support at Data Harvest. Please provide details of:
oThe computer platform it is being used with and the EasySense2 app’s version number.
oA description of the problem being encountered.
USB Port (4)
Use to connect to a computer or a charging unit.
For specific USB or Bluetooth connectivity instructions, please see the 'Connectivity' section of this
documentation.
For instructions on charging your device, see the section on 'Charging the Sensor'.
Unique ID Number (5)
All Smart Wireless Sensors are labelled with a unique ID number. This number is used in the
EasySense2 app, so that you can identify each sensor when making a connection wirelessly.
Flow Heads (6)
Two identical flow heads are fitted to the sensor during use. One will be a permanent fixture the; other
is a user’s individual flow head.
Circular Guard (7)
This is a diameter extender to make one flow head unable to fit into a user’s mouth. It is to be attached
to the flow head that is not changed with user.

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Connectivity
The sensor is both USB and Bluetooth compatible. Install the EasySense2 app, if it is not already on
your device. For details of how to operate the EasySense2 app, please refer to the EasySense2
documentation.
USB Connectivity
Quick Steps
1.Connect the sensor to the computer’s USB port using the USB cable supplied.
2.The computer will automatically detect a new device and depending on your operating system, will
install any applicable device drivers.
3.Start EasySense 2 app.
4.Within the EasySense2 app, the Devices icon will change to green to show that the sensor is
connected, and the status light on the sensor will also turn green.
5.Begin your practical investigations.
Bluetooth Connectivity
Using Bluetooth, the sensor can wirelessly connect to mobile devices such tablets and mobile phones,
as well as desktop or laptop computers, giving students the ability to run experiments independently
without being tethered to a device.
See the EasySense2 app user manual system requirements for further details.
Quick Notes on Bluetooth Connectivity
Only use with the EasySense2 app, you do not need to pair the device. If paired, the sensor will not be
available to the EasySense2 app.
Computers or devices will need to support Bluetooth Low Energy (BLE). For further information refer to
the instructions provided for the EasySense2 app.
Quick Steps
1. Short press the on/off switch to turn the sensor on, blue LED will flash.
2.Open the EasySense2 app.
3.Select the Devices icon.
4. Select your sensor from the list of available sensors to connect to the device. Your sensor is
identified by its unique ID in the list.
5.Click on connect at the side of your sensor in the list.
6. The Devices icon will change to green and the status light on the sensor will flash green to indicate a
connection has been established.
7.Begin your practical investigations.

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Charging the Sensor
The Smart Wireless sensors are fitted with a rechargeable lithium-ion battery and can be charged via
the USB port. Use the supplied USB lead to connect the sensor either directly to a USB port on your
computer, a powered USB hub or a USB mains charger that outputs 5 V at 500 mA or more.
A full charge can take up to 4 hours.
Additional Information
Whenever the sensor is connected to the USB port on the computer or to a USB mains charger (output
5 V at 500 mA or more), it will automatically recharge the battery (LED status flashing white).
When connected to a computer, the computer should be turned on and not in sleep or standby mode,
as the battery may drain instead of charge.
The sensor will stay awake for 5 minutes when Bluetooth advertising (LED status flashing blue).
Lithium-ion batteries are ‘memory-free’ and prefer a partial rather than a full discharge. Constant partial
discharges with frequent recharges will not cause any harm. Frequent full discharges should be
avoided whenever possible. Ideally the sensor should be stored at about 40% or more charge.
The speed at which a lithium-ion battery will age is governed by both its storage temperature
(preferably less than 40 C) and state-of-charge.

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Firmware Updates
Occasionally Data Harvest may release updated firmware which will contain improvements or new
features.
Updates will take place when you connect your sensor to the EasySense2 app. You will be given the
option to decline an update.
Updates can be performed over USB or Bluetooth and will typically take less than one minute. Updating
firmware over USB will be quicker than Bluetooth.
Do not disconnect the sensor, or power off during the update.
If you have a wireless connection to the EasySense2 app, the sensor will have to be reconnected after
performing the update.

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Usage Information
Measurement Procedure
 Sit upright (with good posture) or stand comfortably. If possible, look away from the computer
screen so you cannot view the data as it’s being collected (so you won’t subconsciously alter your
breathing pattern).
 Hold the Spirometer in an upright position.
 Place the flow head’s mouthpiece in your mouth, between the teeth, and make a good seal with
your lips. Keep your tongue flat so it doesn’t obscure the opening.
Note: You may find biting the flow head is a good way to hold it in position.
 If required, attach the nose clip or hold your nose to ensure that all breathing is done through the
mouth. (This is necessary if the results need to be qualitative, but is not normally required for
breathing pattern studies).
 Make time to adapt to breathing into the flow head and practice any procedures you need to follow.
You may find it easier to be talked through each part of the routine or to follow a card of
instructions.
 Breathe quietly in order to become accustomed to the apparatus and attain a stable breathing
pattern. Air expired from the lungs is measured as positive flow, inspired air as negative.
 Rest the Spirometer on the work surface between uses to prevent the heat of your hand affecting
the results.
Note: Don’t expect perfect results first time. The Spirometer is an unnatural breathing device and
time is required to learn how to breathe naturally through it.
Health and Safety considerations
 The flow heads are capable of trapping sub-micron sized microbes. They have cross contamination
efficiency for both bacteria and virus of 99.9% @ 55L/min and 750L/min.
 Each student should use their own flow head. There is a possibility that infective agents trapped in
the filter can become freed during inhalation and breathed back into the test subject’s system. This
represents a point of possible cross contamination. It is not sufficient to simply wipe the mouth
piece of the flow head with an antiseptic wipe and pass the apparatus on to the next subject. This
only cleanses the area in contact with the mouth, it does not disinfect the filter or the internal
surfaces of the flow head.
 The ‘fixed’ flow head will not need to be changed with each use as long as the outlet side is
protected by the test subject’s flow head.
 If the ‘fixed’ flow head is accidentally used by a test subject, then it should be replaced.
 Test subjects should not be overstressed by the activities that use the Spirometer. The instructor
should make efforts to check the subject is healthy and has no history of cardiovascular or
respiratory problems e.g. asthma.
 The nature of the Spirometer means that some subjects will feel discomfort when using the
apparatus. Efforts should be made to put the test subject at ease. Stop the investigation if the test
subject’s discomfort becomes too great.
 The length of the apparatus should not be increased under any circumstance. The apparatus does
not contain a flow control valve and therefore increases the anatomical dead space of the subject.
Practical notes
 Do not try to force the flow heads into the plastic moulding as this could damage the moulding and

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cover the sensing hole.
 Best results are obtained if the test subject has become used to breathing through the apparatus
before commencing an investigation. A five minute acclimatisation period is recommended. With
experience and practice the pattern becomes normal.
 It is quite normal for the test subject to experience increased salivation when they first use the
Spirometer. Keep the flow heads in the upright position to avoid problems with condensation
developing.
 After prolonged use the inside of the spirometer’s housing tube may become coated with
condensation. It is advisable to check for this occasionally and wipe away as needed. The amount
formed will depend upon the temperature of the room and the level of breathing.
 The nose clip is used to prevent air from entering or leaving the nose as the subject is breathing. It
should be used if the results need to be qualitative, e.g. during volume measurements when the air
that passes through the nose should not be included. For studies and comparison of breathing
patterns a nose clip is not necessary.
 Make sure that when the Spirometer is in the test subject’s mouth that there is a good seal and
that the tongue is kept flat so it does not obscure the opening (they may find biting the Spirometer
tube is the best position)
 Two small lugs are moulded into the housing tube; these have been provided for a thin line or
lanyard (e.g. a glasses lanyard) to be attached to support the Spirometer during use.
 The flow heads carry the and are made from plastic recycle type 5: Polypropylene (PPE). They also
carry a ? mark to indicate and confirm that they are for single use (individual) only.
 If the Spirometer is used with a data logger that records 10 bit instead of 12 bit data (e.g.
EasySense Flash, Q3 or Q5) the quality of samples will be lower. This will become more noticeable
when data is used to perform calculations (e.g. to derive volume).
 A 20 ms intersample time (or less) is recommended for the best results.
NOTE: Single use (individual) only logo.
Ranges
 AirFlow – the default range of the Spirometer. This returns a simple change in flow over time.
 Volume – the airflow has simple integration applied to arrive at a volume range. The volume
range is prone to drift due to residual flow data included into the integration. Calculations within
the software can also produce volume form flow and apply an adjustment to correct for drift.
 Adjusted volume – returns a corrected for drift volume. This is accomplished by ensuring that
any point with zero flow has a zero volume; in the data collected you may see “jumps” in the
data as the correction is made. Ideal for showing ventilation details (inspiratory reserve,
expiratory reserve etc).
 Cyclic volume – gives a volume reading with a baseline of zero. Ideal for measurements of tidal
volume.
 Breathing rate – the data is analysed for peaks to give “breaths per minute”. You will need at
least two inhalations to start showing this data and you will get data after you stop breathing
due to the analysis taking place.
 Differential pressure – this is the raw data; it shows the pressure changes with time.
Background

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The Spirometer is used to measure both the amount of air that moves in or out of the lungs and how
quickly the air is expelled from the lungs.
 The amount of air that moves in or out of the lungs during any one breathing cycle is called the tidal
volume. Tidal volume is typically 0.5 litres.
 After normal inspiration it is possible to breathe in additional air – this is called the inspiratory
reserve volume.
 Similarly, after normal expiration, it is possible to exhale additional air from the lungs – this is called
the expiratory reserve volume.
 Even if the expiratory reserve volume is fully expelled from the lungs, there is still a volume of air in
the lungs, called the residual volume, which cannot be exhaled. The residual volume has a very low
oxygen and high carbon dioxide concentration.
 Upon inhalation fresh air mixes with stale air from the residual volume to create air in the alveoli
that still has gas concentrations that facilitate the diffusion of oxygen into and carbon dioxide out of
the capillaries.
 The respiration centre in the medulla ensures that gaseous exchange at the lung matches the
requirements of the body. During times of increased demand, the tidal volume can be increased,
using some of the reserve lung volumes to bring more fresh air into the body. In addition, the rate of
breathing and the rate of air movement in and out of the lungs can be changed.
Glossary of Abbreviations
Term Abbreviation Description
Spirometric values FVC Forced Vital Capacity: the total
volume of air that can be
forcefully exhaled after maximal
inspiration
FEV1 Forced Expiratory Volume in
one second: the volume of air
that can be exhaled in 1 second
after a maximal inhalation
FEV6 Forced Expiratory Volume in 6
seconds
FEV1/FVC% The Forced Expiratory Volume
in one second as a percentage
of the forced vital capacity
MVV Maximal Voluntary Ventilation:
the maximum volume of air that
can be exhaled under forced
exhalation
PEF or PF Peak Expiratory Flow or Peak
Flow: the maximum flow
achieved at the beginning of the
FVC manoeuvre
Lung volumes ERV Expiratory Reserve Volume: the
maximum volume of air that can
be exhaled after a normal end of
expiration
IRV Inspiratory Reserve Volume: the
maximal volume of air that can
be inhaled after a normal end of

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inspiration
RV Residual Volume: the volume of
air remaining in the lung after a
normal exhalation
Lung capacities TV Tidal Volume: the volume of air
that is inhaled or exhaled with
each respiratory cycle whilst
breathing without effort
FRC Functional Residual Capacity:
the volume remaining in the
lung after a normal end
expiration
IC Inspiratory Capacity: the
maximal volume of air that can
be inspired from a normal
resting expiratory level. IC = TV
+ IRV
TLC Total Lung Capacity: the volume
of air in the lungs at maximal
inflation
VC Vital Capacity: the largest
volume measured on complete
exhalation after full inspiration.
VC = TV + IRV + ERV

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Practical Investigations
The Smart Wireless Spirometer best data notes:
To get the best data from any practical
 Make sure the sensor is held vertically during data collection
 Use the calibrate before any data collection to give a zero value for zero airflow (minimise any
potential data drift)
 Start data collection during an exhalation
The Smart Wireless Spirometer can be used to investigate a number of scientific experiments such as:
 Measurement of tidal volume
 Breathing patterns before, during, and after exercise
 Lung capacities
 Lung efficiencies FVC, FEV1 and FEV6, MVV (also known as Forced Vital Capacity)
 Flow volume curves
 Slow Vital capacity (SVC): The user should breathe normally 3 times and then inhale to the
maximum extent of total lung capacity and then expire to the maximum extent
 Maximal voluntary ventilation (MVV): The user should breathe as deeply and as rapidly as possible
over a period of 6 to 12 seconds
Note: Care should be exercised when performing this test as there is a danger of
hyperventilation. Ensure the test subject is sitting down.
Care and maintenance.
 After use wipe the inner surface of the spirometer with anti-bacterial wipes.
 Remove the flow head used by the user and discard, they are single use.
 Store with the “fixed” flow head and guard in position.
 Make sure the spirometer is dried out from use – if necessary leave out to dry overnight – any
residual moisture has the potential to allow unwelcome microorganisms to grow.
 After several uses (lessons, not individual) consider replacing the fixed head.
The flow heads are 90%+ effective in trapping bacteria and fungal spores, and will offer high resistance
to transfer of viral particles in moisture droplets.
The moisture trapped in the filter of a user’s flow head makes it unacceptable to save the filters for use
“another day”.
Online Videos
Learn how to use data logging in the classroom with our Secondary Science Academy demonstration
videos, which will walk you through using the new EasySense2 app and show you how to get hands-on
with the latest Bluetooth wireless sensors. The video experiments will show you how to get the best out
of your science lessons.
New online content is being continuously uploaded onto our YouTube channel, including practical
worksheets as well as videos.
See our website for further information and links.

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Explore Bluetooth Sensors
Are you looking to make the jump to our smart
wireless sensors? Or have you recently purchased
them and want to know more about how they
work?
View video playlist
Explore EasySense2
The core of our science platform is our
EasySense2 software. In these videos you will
learn everything from the basics of our software to
the most in-depth features.
View video playlist
Explore Science Practicals
See our Smart Wireless Sensors in action with a
range of practical experiments. This is the best
way to get started with the new Bluetooth sensors!
View video playlist

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Sensor Specifications
Please read the following table for sensor specifications.
Feature Detail
Measurement Ranges Airflow, ±10L/s
Volume, ±100L
Adjusted Volume, ±100L
Cyclic Volume, ±100L
Breathing Rate, 0 to 50 BPM
Differential Pressure, ±2kPa (±20cmH2O)
Resolution Airflow, 0.01L/s
Volume, 0.01L
Adjusted Volume, 0.01L
Cyclic Volume, 0.01L
Breathing Rate, 0.01BPM
Differential Pressure, 0.001kPa
Fastest logging speed 5ms (200Hz)
Connectivity Wired via USB
Wireless via Bluetooth
Bluetooth Specifications Bluetooth 4.2 low energy radio, single mode
compliant
Transmit (TX) power: 0 dBm
Receiver (RX) sensitivity: - 90 dBm
Usable transmission range: up to 10 m in open
air
Frequency Range: 2.402 to 2.480 GHz operation
Operating range: 0 - 40 C and 0 to 95% RH (non-
condensing)
Internal Battery Rechargeable internal lithium-ion 3.7 V
Power specification: 5 V at 500 mA
Storage/Operating Temperature 0 - 40 C
Humidity 0 to 95% RH (non-condensing)
Physical Specifications Weight: approx. 80 g
External dimensions: approx. height 45 mm x
width 55 mm x length 135 mm

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Limited Warranty
For information about the terms of the product warranty, see the Data Harvest website at: https://data-
harvest.co.uk/warranty
Product Repairs
When returning goods to Data Harvest, please download and complete the repair return form to ensure
you have sent us all the information we require, and send it to us alongside the item to be repaired. The
second page of this form includes a return address label.
If you have purchased a Data Harvest manufactured product via a different company, please also
supply proof of purchase.
Postage Charges
 In the event of a fault developing, the product must be returned in suitable packaging to Data Harvest
for repair or replacement at no expense to the user other than postal charges.
 There will be no postal charge for the return of repaired goods to any mainland UK address (for other
areas, additional shipping charges may apply).
Out of Warranty Repairs
Please visit https://data-harvest.co.uk/repairs for the most up to date charges for out of warranty
repairs.
Warranty on Repaired Items
Once an item has been serviced and repaired, the product will have 1 year warranty against further
failure of the component repaired.
International Returns
Please contact the authorised Data Harvest representative in your country for assistance in returning
equipment for repair.

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Compliance
This product complies to the following standards
Waste Electrical and Electronic Equipment Legislation
Data Harvest Group Ltd is fully compliant with WEEE legislation and is pleased to provide a disposal
service for any of our products when their life expires. Simply return them to us clearly identified as ‘life
expired’ and we will dispose of them for you.
FCC Details
This device complies with Part 15 of the FCC Rules. Operation is subject to the following two
conditions: (1) this device may not cause harmful interference, and (2) this device must accept any
interference received, including interference that may cause undesired operation.
CE
This product conforms to the CE specification. It has been assessed and deemed to meet EU safety,
health and environmental protection requirements as required for products manufactured anywhere in
the world that are then marketed within the EU.
UKCA
This product conforms to the UKCA specifications.

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Troubleshooting
If you experience any problems with your product, please try the following troubleshooting tips before
contacting the Data Harvest support team.
Feature Detail
Loss of Bluetooth Connectivity If the sensor loses Bluetooth connection and
will not reconnect try:
Closing and reopening the EasySense 2 app.
Switching the sensor Off and then On again.
If you are using a Bluetooth Smart USB Adaptor
on your computer, unplug the adaptor, plug back
in again and try to reconnect.
Hard reset the sensor and then try to reconnect.