Pressure receptacles in composite materials
For composite cylinders, tubes, pressure drums and bundles of cylinders which make use of
composite materials, the construction shall be such that a minimum burst ratio (burst pressure divided
by test pressure) is:
- 1.67 for hoop wrapped pressure receptacles;
- 2.00 for fully wrapped pressure receptacles.
Closed cryogenic receptacles
The following requirements apply to the construction of closed cryogenic receptacles for refrigerated
If non-metallic materials are used, they shall resist brittle fracture at the lowest working temperature
of the pressure receptacle and its fittings.
The pressure relief devices shall be so constructed as to work perfectly even at their lowest working
temperature. Their reliability of functioning at that temperature shall be established and checked by
testing each device or a sample of devices of the same type of construction.
The vents and pressure relief devices of pressure receptacles shall be so designed as to prevent the
liquid from splashing out.
General requirements for aerosol dispensers, small receptacles containing gas (gas cartridges) and fuel cell cartridges containing liquefied flammable gas
Design and construction
Aerosol dispensers (UN No.1950 aerosols) containing only a gas or a mixture of gases, and small
receptacles containing gas (gas cartridges) (UN No. 2037), shall be made of metal. This requirement
shall not apply to aerosols and small receptacles containing gas (gas cartridges) with a maximum
capacity of 100 ml for UN No. 1011 butane. Other aerosol dispensers (UN No.1950 aerosols) shall be
made of metal, synthetic material or glass. Receptacles made of metal and having an outside diameter
of not less than 40 mm shall have a concave bottom.
The capacity of receptacles made of metal shall not exceed 1 000 ml; that of receptacles made of
synthetic material or of glass shall not exceed 500 ml.
Each model of receptacles (aerosol dispensers or cartridges) shall, before being put into service,
satisfy a hydraulic pressure test carried out in conformity with 18.104.22.168.
The release valves and dispersal devices of aerosol dispensers (UN No.1950 aerosols) and the valves
of UN No. 2037 small receptacles containing gas (gas cartridges) shall ensure that the receptacles are
so closed as to be leakproof and shall be protected against accidental opening. Valves and dispersal
devices which close only by the action of the internal pressure are not to be accepted.
The internal pressure of aerosol dispensers at 50 °C shall exceed neither two-thirds of the test pressure
nor 1.32 MPa (13.2 bar). They shall be so filled that at 50 °C the liquid phase does not exceed 95% of
their capacity. Small receptacles containing gas (gas cartridges) shall meet the test pressure and filling
requirements of packing instruction P200 of 22.214.171.124. In addition, the product of test pressure and water
capacity shall not exceed 30 bar.litres for liquefied gases or 54 bar.litres for compressed gases and the
test pressure shall not exceed 250 bar for liquefied gases or 450 bar for compressed gases.
Hydraulic pressure test
The internal pressure to be applied (test pressure) shall be 1.5 times the internal pressure at 50 °C,
with a minimum pressure of 1 MPa (10 bar).
The hydraulic pressure tests shall be carried out on at least five empty receptacles of each model:
(a) until the prescribed test pressure is reached, by which time no leakage or visible permanent
deformation shall have occurred; and
(b) until leakage or bursting occurs; the dished end, if any, shall yield first and the receptacle
shall not leak or burst until a pressure 1.2 times the test pressure has been reached or passed.