Pulse Online Help

Accessible to all Pulse customers, Pulse Online is a web-based system for centrally storing test files, performing detailed analysis and generating professional test reports. Designed to work on all modern web browsers, Pulse Online is mobile friendly and accessible on phones and tablets whilst working on site. Simply upload PAT or CSV test files from your Pulse device via the Import Files page in order to get started.

There is currently no online user management facility. If you would like to give access to a colleague or employee to view and manage the same Pulse tests as you, please contact us and we will arrange for user details to be created for them.

To use Pulse Online, you first need to import test files that have been downloaded from your Pulse device(s). To obtain these, simply navigate to the test history page on your Pulse control unit, connect a USB storage key and download your selected tests.

Once you have transferred the files to a computer, upload them using the 'Import Files' page by either manually selecting them or dragging and dropping them onto the page. Once uploaded, you will be prompted to confirm the person who performed each test as well as a unique Building Reference. Select 'Save Files' to complete the import process.

There is no limit to the number of test files that can be uploaded in a single go. Once uploaded, the test files are saved to your account indefinitely.

Once successfully imported, select 'View Tests' from the top menu and you will see a full list of all uploaded test files. Click any of the headings in this table to sort them, e.g. by test date, reference, postcode, status or upload date. You can also filter tests by year or month, expand and collapse the view from 10 to 100 tests per page and search the full set of records by their reference.

On the main 'View Tests' page, tick the checkbox next to the tests you wish to delete. Scroll to the bottom of the page and select 'Delete checked'. You will be asked to confirm that you wish to delete the selected tests.

From the 'View Tests' page, search or filter to find the test that you wish to view and select 'View Test'. From here you can view the results summary, key test parameters and data charts.

Adding a property address to a Pulse test allows you to search by postcode and group together multiple tests carried out at the same property. You can add a property address when viewing an individual test. On the 'Building' tab, use the address lookup facility to find the correct property address.

The address lookup facility uses Royal Mail's PAF file and includes 'Not Yet Built' data which should include new build properties still under construction. For best results, try entering just the house number and postcode, i.e. "12, AB3 4CD".

If you still can't find the correct address, an option will appear to 'Enter address manually'. Manually entered addresses will not be validated and it will not be possible to produce a certified test report for them.

Two reasons, the first is so that local weather conditions for the time and date of the test can be included in the report. The second is so that other measurements for the same property can be stored and reported upon more easily. For example, if Build Test Solutions products for thermal performance and U-value measurement have also been used on the same property.

It is not possible to edit any aspect of the pressure and flow data recorded on-site by the Pulse equipment. A tester may, however, edit details about the building including its envelope area and volume as well as contextual information such as its age, form and construction type. Whilst the contextual information has no bearing on the test result, it does add richness to any onward reporting or data analysis.

If you edit either the envelope area or volume, a new Pulse result will be calculated based on the new building dimensions.

The Pulse device measures the air leakage directly at 4Pa. This is a pressure level most representative of day-to-day conditions, making it well suited to assessing background leakage or to more reliably determine an infiltration rate for energy performance calculation purposes with minimal extrapolation.

Here at Build Test Solutions, we are strong advocates of a 4Pa reference pressure but we also accept that the fan method can't go this low and that 50Pa is currently more widely understood and referenced. Pulse Online, therefore, uses the measured data to automatically extrapolate the result up to 50Pa. Whilst this can be done using the Power Law, the UK Building Regulations and Pulse Online instead use the following conversion formula derived by calculating the ratio of the measured air permeability at 4Pa (AP4) from the Pulse test to the measured air permeability at 50Pa (AP50) from a fan test over a wide range of leakage rates.

AP50 = AP40.9241 x 5.2540

A building or enclosure will present itself as being leakier when higher pressure is exerted upon it. As well as this, however, higher pressures can also force what is termed as 'convoluted leakage paths' which might establish themselves when a large fan is mounted to the doorway but not when Pulse testing or indeed during normal conditions or in gusting winds.

Other differences include that that fan requires an external doorway to be open with the system used for fan mounting often also being leaky.

This will usually be as a result of many of the factors described above. It can however also be a consequence of the error associated with extrapolating the Pulse data up to 50Pa (the cited achieved pressure range are the pressures as which Pulse has directly measured the air leakage).

Other factors can include variations in the test set-up and changes on site, especially when testing is conducted at different times by different testers. Fundamentally they are two different tests carried out at two different pressures and absolute agreement would not be expected.

The calculation details give advanced diagnostic information about a Pulse result:

Correlation (r²)

The correlation coefficient, or r², is indicative of the accuracy with which a curve fitting equation can be applied to a set of results. With high-frequency 50Hz data collection, 25 reference points are collected per step and it is recommended that an overall r² value of greater than 0.96 for a test to be deemed valid. Tests that do not obtain this minimum value may be due to adverse environmental conditions or poor test conditions or techniques.

Air Flow Exponent (n)

The airflow exponent, n, is used to describe the airflow regime through the gaps and holes in the building fabric. Values must range between 0.5 and 1.0. An n value approaching 0.5 signifies turbulent flow, representing high flow through large apertures. An n value approaching 1.0 will indicate a more laminar flow, characteristic of more airtight structures or those with much smaller gaps and holes.

Air Flow Coefficient (CENV)

The airflow coefficient, CENV, is a measure of the efficiency with which air flows through the gaps, cracks and holes in the structure at an internal-to-external pressure difference of 1Pa.

Air Leakage Coefficient (CL)

The air leakage coefficient, CL, is obtained by correcting the airflow coefficient, CENV, to standard conditions (i.e. 20°C and 101,325 Pa).

Calculator Version

Reference number as to the version of the Pulse software that was used to calculate the result.

Calculation Method

The method used to determine which combination of steps were used to generate the result. By default, the step combination with the best overall r² value will be selected.

The timings allow advanced users to adjust the Pulse data analysis routine:

Steady State

Steady-state is the period over which a polynomial fit is performed to determine a smoothed curve and a derivative of the air pressure and tank pressure.

The Steady-State Offset is the start of the defined steady-state period, offset from the point the valve opens. This is defaulted at 0.5 seconds but may be manually adjusted >= 0.3 secs.

Steady State Duration must be >= 0.4 secs and the sum of the Steady State Offset + Steady State Duration must not be longer than the total pulse valve open duration (typically 1.5 secs or 4 secs when testing more airtight enclosures).

Narrow State

The Narrow-State sits within the Steady-State and is the period when data samples of air pressure and air leakage are collected for analysis. The sum of the Narrow State Offset + Narrow State Duration must be <= Steady-State Duration.

Pulse Online will always use the latest version of our software to calculate the result. We are constantly optimising the algorithm used in calculating the air leakage result and if your control unit is giving a different result, it may be that it is not using the latest firmware version. Updating the control unit to the latest firmware version should resolve the issue.

A test status warning is given where the achieved pressure range does not span 4Pa. The warning will state 'low pressure' if the maximum of the range is below 4Pa and 'high pressure' if the minimum of the range is above 4Pa. This does not invalidate the test but means that the result at 4Pa has had to be inferred based on the available data. This is then reflected in the calculation uncertainty. Where these instances occur, the closer the achieved pressure range is to 4Pa, the better.

Low achieved pressure is a result of the building under test being either too big and/or too leaky for the Pulse equipment in use. To increase the achieved pressure, an additional air receiver should be added.

High achieved pressure is a result of the Pulse equipment releasing too much air into the building under test. In these instances, the operative could use fewer air receivers and/or carry out the test from a lower air receiver charge level i.e. fewer bars.

There are several criteria for fitness to ensure that pulse test results are accurate and dependable. As a pulse test can consist of several steps, tests can be presented with only some of the steps used in order to get a passing test, however, this isn't always possible based on the test and in some cases, every step combination can fail. In this case, the result presented using every step, and the reasons for the test failing will be presented under; Results > Test Information > Status Reason. The reasons for test failure and possible actions that may be taken are detailed below.

There are a number of reasons why a test will be invalid, please refer to the following:

Invalid r² Threshold

The correlation coefficient, or r², is indicative of the accuracy with which a curve fitting equation can be applied to a set of results. With high-frequency 50Hz data collection, 25 reference points are collected per step and it is recommended that an overall r² value of greater than 0.96 is required for a test to be deemed valid. Where all combinations of the test steps are analysed yet none are able to achieve the minimum 0.96 threshold, the test is flagged as invalid. The quality of the data points and trendline can be viewed in the 'Air Flow' chart of the View Test page, with poor r² tests typically presenting a distorted series of data points.

These distortions will typically be as a result of either:

• Adverse environmental conditions e.g. strong gusting winds;
• Poor test conditions e.g. a loose or moving element of the building fabric that is constantly moving and changing or reacting to the Pulse of air inconsistently;
• Substandard test setup e.g. distorted airflow and reverberations as a result of the air receiver or controller being too close to a wall or window.

Invalid Exponent Threshold

The air flow exponent, n, is used to describe the airflow regime through the gaps and holes in the building fabric. Values must range between 0.5 and 1.0. An n value approaching 0.5 signifies turbulent flow, representing high flow through large apertures. An n value approaching 1.0 will indicate a more laminar flow, characteristic of more airtight structures or those with much smaller gaps and holes.

A test would fail on this criteria if the n exponent is outside of the 0.5 to 1.0 range. A value that is below 0.5 would typically be caused by a building having a series of very large openings. This could be as basic as there being an open window or chimney but it could also simply mean that the building is just too leaky overall and outside of the operating range of the Pulse equipment in hand.

It is very rare for an n exponent of more than 1.0 to be recorded but if it is, we advise assessing the achieved pressure range, perhaps repositioning the equipment e.g. ensuring the controller is not in the turbulent flow from the air receiver nozzle, then retesting.

Invalid Steps

As with the test as a whole, individual steps have their own pass and fail criteria, however, one step failing doesn't mean that other steps have also failed. If a test presents an 'Invalid steps' fail message, then this means that the final result calculation included at least one step which failed. The reasons for why steps have failed will be displayed on the 'Parameters' tab when viewing a test.