What is a lung function test?

A lung function test is a procedure which measures a number of different aspects of lung performance.  The technique used is known as spirometry, and is a quick yet effective way of determining the capabilities of your airways.

Why should I need a lung function test?

Unfortunately, even in our normal environment, the air that we breathe is not as clean as we may wish.  If we are exposed to additional hazards due to our work such as dust or fumes, this adds to the pollutants we are constantly breathing in.  Many of these pollutants do not cause any harm as our normal defences are sufficient to trap and remove most particles before they reach the lungs.  However if these defences prove inadequate under some conditions, our body recognises this and responds in several ways to attempt to control such undesirable exposure.  Sometimes these responses themselves can become a problem and give rise to tightness within the chest, increased phlegm production and shortness of breath.

How will a lung function test help me?

A lung function test will measure closely any changes in your respiratory performance.  Several tests are compared over time and gradual change in the condition of your airways can be closely monitored, giving both yourself and medical staff the opportunity to advise on any necessary precautions or actions before any permanent damage occurs.

Before the test

Before the test you should avoid taking any respiratory medication prior to attending your test appointment. This will include inhalers, some antihistamines and other tablets.

Please make every effort to:

  • Not wear tight clothing for your appointment that constricts your lungs or stomach.
  • Not smoke for at least one hour before your appointment.
  • Not take part in vigorous exercise for up to thirty minutes before your appointment.
  • Avoid consuming a heavy meal up to two hours before the appointment
  • Not consume alcohol for a minimum of four hours.

For the day of the test you will be given an appointment time. Please arrive ideally 5 minutes before the test to allow you to sit down, relax in a quiet environment, which improves the accuracy of the test, and complete a questionnaire if you haven’t already done so. If you have been given the questionnaire in advance, please try to complete it as fully as possible before attending and ask the occupational health professional if you have any queries. Please bring with you any respiratory protection (masks) that you normally wear at work, to show the tester.

What will the test involve?

The test itself will be supervised by our experienced staff. There are some reasons when lung function tests may not be performed. These include:

  • Heart attack within the last month
  • Any recent surgery to eyes, chest or stomach
  • Pneumothorax (collapsed lung)
  • Current or recent chest infection (within the past two weeks)
  • Chest pain on the day of your test
  • High blood pressure that cannot be controlled.

For the test itself you will be seated and your nose may be sealed with a nose clip. You will be given instructions by the occupational health professional on how to breathe into the mouthpiece. You will be instructed to take a full deep breath in and then blow out as fast as possible keeping going until your lungs are empty. This will be performed a minimum of three times.

The screening will only take a few minutes and at the end of the test you may be given brief advice on how to correctly wear respiratory protection etc, and on the importance of abiding by the Company’s Policy with the safe use of chemicals at work. If the test suggests you have a problem with your breathing you will be advised at the time.

After the lung function test

A report providing anonymised results of the screening will be sent to your Company. If your results suggest there may be a problem with your breathing the occupational health professional will obtain your consent and a copy will be sent to your general practitioner for possible further investigation. You may also be required to attend an occupational health physician for further health and work advice from which he/she will be able to provide your company about any reasonable adjustments that may need to be undertaken.

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