The Transportable Pressure Vessels Regulations 2001

1.  These Regulations shall not apply to— E+W+S

(a) gas cylinders used as a component part of breathing appliances;

(b) UN 2857 REFRIGERATING MACHINES containing non-flammable, non-toxic, liquefied gas or ammonia solutions (UN 2672) or UN 3358 REFRIGERATING MACHINES containing flammable, non-toxic, liquefied gas, provided those machines—

(i) contain less than 12 kg of gas, and

(ii) are protected and stowed so as to prevent damage to the refrigeration system;

(c) UN 1044 FIRE EXTINGUISHERS with compressed or liquefied gas, provided—

(i) those extinguishers are packaged in strong outer packagings, and

(ii) have protection against inadvertent discharge; or

(d) UN 3164 ARTICLES, PRESSURIZED, PNEUMATIC OR HYDRAULIC (containing non-flammable gas), designed and manufactured to withstand stresses greater than the internal gas pressure by virtue of transmission of force, intrinsic strength or construction provided those articles—

(i) are packaged in strong outer packagings, and

(ii) in the case of articles intended to function as shock absorbers, comply with Special Provision 283 of Appendix 1 to the Approved Carriage List.