I felt to share a legal notce I am personally carrying around that understates legal exemption from wearing a mask plus a conditional letter of acceptance should someone want to force me to do so - I would hold them personally liable for the health consequences. This is all lawful under the jurisdiction of the Common Law. However I do suggest you research your rights. There is also a badge to print out and wear, should you choose to, from the British Lung Foundation. For a limited period of time, you may download all of them freely from Openhand's drop box here...
Openhand DropBox Exemption Folder

Here is the content of the noitce of conditional acceptance and liability...

Notice of Conditional Acceptance

This is to notify you that I am happy to wear a mask as directed, on the condition that you provide the following:

1. Proof that use of such masks can prevent the inhalation of substances or micro-organisms at the scale of “viruses”.

2. Proof that prolonged use of such a mask will NOT cause Hypercapnia, Hypercarbia or Respiratory Acidosis in the wearer.

3. A signed and witnessed statement from you, accepting full responsibility and full commercial liability should I be subsequently diagnosed with Hypercapnia, Hypercarbia or suffer an Asthmatic attack or any other respiratory distress resulting from prolonged mask wearing.

4. A complete list of your medical qualifications.

Please use the space below to provide the requested proofs of claim and sign and date it in the appropriate boxes to accept full responsibility and full commercial liability. Failure to do so will be deemed to mean no such proof exists and that you are not medically qualified to make a determination of the effects of prolonged mask use, and/or you are not confident enough to take financial responsibility for my safety as a result of your mask enforcement actions.

Please provide the requested proof and medical qualifications here:

Liability Statement

I, ………………………………. as the official enforcing the unlawful wearing of masks according to parliamentary preference, am fully aware that prolonged use of surgical and non-surgical masks reduces the levels of Oxygen that reach the wearer and increases the dangerous levels of Carbon Dioxide and toxins that are expelled via the breath. I am also aware that prolonged mask use increases the risk of Hypercapnia, Hypercarbia, Asthma and other forms of respiratory distress.

I understand the consequences for the violation of the ‘Nuremburg Treaty of Human Rights’ and that Government directive may not be Law.

I therefore accept full responsibility and full commercial liability for any violation of Human Rights with the fee of £1.00 per second up to a maximum of £75,000 for the first offence and up to a maximum of £150,000 for any subsequent offence or should the bearer experience, or be subsequently diagnosed with any of the above conditions as a result of prolonged mask use.

Signed in the presence of two witnesses:

Dr/Mr/Ms. ……………………………………… Autograph: ………………….…………….……….. Date:…………….

Address: …………………………………………….…………..………………….………………………………..…

………………..………………….………………………..………………….……………………………….………...

Witness: ……………………………………………. Autograph: ………………….……………….………….. Date:…………....

Address: …………………………………………….…………..………………….………………………………..…

Witness: ……………………………………………. Autograph: ………………….……………….………….. Date:………………

Address: …………………………………………….…………..………………….………………………………..…

Here's a mask exemption card you can get from the British Lung Foundation to wear...