Pressurisation systems are a major topic in the smoke ventilation industry at the moment - this blog will delve into the testing of said systems.
Instead of going into detail of the tests, which we’ll save for a future post, this post will give you an overview of the tests, tell you where to find the information you need and point out some key considerations.
The first place to look for information on testing pressurisation systems is in BS EN 12101-6, Section 12 - Acceptance testing.
There are five acceptance tests detailed here:
1. Pressure differential
2. Net pressure differential
3. Air velocity
4. Door opening force
5. Activation of system.
The first test, pressure differential, is designed to establish the pressure differential due to wind forces and the stack effect without the pressurisation system running.
The second test, net pressure differential is to establish the pressure differential between the pressurised zone and the accommodation with the system running.
The third test is to measure the air velocity, through an open door separating a pressurised and unpressurised space.
The fourth test is measuring the door opening force and is done to make sure the doors between pressurised and unpressurised spaces can be opened within 100N force (to make sure people can evacuate).
The fifth and final test is to check that the pressurisation system activates when a trigger is received by the fire detection system.
In buildings higher than eight storeys, first and second tests should be carried out in groups of eight floors.
The tests can only be carried out when the installation is complete and the pressure differential system, and where applicable air conditioning, have been commissioned and correctly balanced. All building work will also need to have been completed - even down to things like carpets and door ironmongery installation as these things can all affect these tests.
The SCA Guide also adds some additional recommendations. Lots of these recommendations are similar to procedures that’d be carried out for the testing of all other smoke ventilation systems, for example, checking that all dampers work, checking automatic changeovers operate for standby fans and power supplies, etc. The full list can be found in section 9.3.6.
Next, is the equipment you’ll need for testing a pressurisation system. Whilst this isn’t an exhaustive list of the equipment you might need, there are three key devices that you’ll need. All of these devices will need to be calibrated to have a tolerance of plus or minus 5% accuracy.
Firstly is a manometer which measures air pressure. This is used in the first two tests.
Second is an Anemometer. This measures air velocity and will be used in test three. Similarly to testing MSVS extract rates at a damper, eight measurements are taken over the doorway in question and find the average velocity.
Finally, a Force gauge. This is used in test four. This is attached to the door handle, the door latch is disabled, and there would then be pull in the direction of door opening, measuring the highest force achieved.
If you have any questions regarding this topic, please don’t hesitate to contact us and speak to our friendly team who will be happy to talk you through the options available. If you’d like to continue learning about smoke ventilation, you’ll find some helpful resources on our blog and YouTube channel.