(1)If the person to whom a direction is duly given under section 137 contravenes, or fails to comply with, any requirement of the direction, he shall be guilty of an offence.
(2)If a person intentionally obstructs any person who is—
(a)acting on behalf of the Secretary of State in connection with the giving or service of a direction under section 137;
(b)acting in compliance with a direction under that section; or
(c)acting under section 137(4) or (5);
he shall be guilty of an offence.
(3)In proceedings for an offence under subsection (1) above, it shall be a defence for the accused to prove that he has used all due diligence to ensure compliance with the direction, or that he had reasonable cause for believing that compliance with the direction would have involved a serious risk to human life.
(4)A person guilty of an offence under this section shall be liable—
(a)on summary conviction, to a fine not exceeding £50,000;
(b)on conviction on indictment, to a fine.