BASIC NOMENCLATURE ACCORDING TO TECHNICAL RULES TPG 304 03
Safe distance – the distance between the source of the hazard and the target (persons, equipment, environment) that ensures acceptable risk to a foreseeable limit. The hydrogen filling station is both the source of the hazard and the target. The situation is the same with the equipment around the hydrogen filling station in relation to it. The safety distance can be reduced by additional safety measures.
Safety distance – the minimum distance between the source of a hazard and an object that is necessary to mitigate the effect of a likely foreseeable event and prevent a minor incident from escalating into a major incident.
Hydrogen Filling Station Operation Risk Assessment – Determination of a quantitative or qualitative risk value for specific situations and recognized hazards of a hydrogen filling station under normal operating conditions. The committee's risk assessment report is part of the project documentation.
Compressor – A device that compresses the hydrogen supplied through the suction line to at least the maximum operating pressure of the mobile equipment tank.
Mechanical disconnect – A device that prevents the filling hose from breaking, damaging the dispensing device and dislodging the filling quick coupling.
Maximum Working Pressure (MWP) - The maximum pressure to which the hydrogen filling station can be subjected in operation at a given process position, independent of the hydrogen temperature, before intervention by means of means to ensure that it is not safely exceeded or reduced, e.g. by safety valves.
Contingency – Any unplanned situation in the normal operation of a hydrogen filling station which may cause or will cause injury to health, damage or loss of property, materials, environmental damage or loss of business.
Danger Zone – An area in which an explosive atmosphere exists or may occur in such quantity that special precautions must be taken in the design, installation, and use of the hydrogen filling station.
Non-public hydrogen filling station – a station that serves a closed group of customers, e.g. a company station.
Nominal Working Pressure (NWP) - the pressure to which the device is set at a hydrogen temperature of 15 °C; typical values for cars are 700 bar, for buses and trucks 350 bar
Operator – a person qualified to operate the equipment
Hydrogen flow restrictor – Device that shuts off the hydrogen flow when a predetermined hydrogen flow limit is reached, which is typically 60 g/s of hydrogen.
Filling overpressure – The pressure at which the gas is supplied to the mobile equipment.
Filling connection – A component of a dispensing rack or apparatus consisting of a flexible connection (filling hose), a mechanical disconnection and a filling quick coupling.
Hydrogen filling station – A device for filling the pressure tanks of mobile equipment with compressed hydrogen. It consists of a hydrogen source, a compressor, a refrigeration unit, high-pressure storage tanks, dispensing equipment and, where appropriate, other accessories.
Slow filling station – a filling station without a high-pressure compressed hydrogen storage tank, where the mobile equipment tank is filled directly from the compressor discharge line.
Working Pressure (WP) - The highest pressure expected for a hydrogen filling station at a given process position in normal operation.
Non-explosion hazard area – An area in which an explosive atmosphere is not expected to be present in such quantities that special precautions must be taken in the design, installation and use of the hydrogen filling station.
Operational pressure leak test – A leak test carried out on equipment in operation.
Quick-fill station – a filling station with a high-pressure compressed hydrogen tank, allowing rapid filling of the tank of one or more mobile devices simultaneously by overfilling.
Suction line – the hydrogen supply line from the low pressure tank to the inlet of the compressor.
Pressure leak test – A procedure for verifying that the equipment under test meets the leak requirements.
User – The operator of the mobile equipment or the driver of the mobile equipment or the operator of the hydrogen filling station, i.e. a person over 18 years of age familiar with the operation of the compressed hydrogen filling equipment.
Public hydrogen filling station – a station that allows the sale of hydrogen to mobile devices to the general public in accordance with Act No 311/2006 Coll.
Ventilation – the exchange of air in a space by the action of natural convection (wind action, temperature gradient), forced convection (fan action) or a combination of both.
Hydrogen – a gas of the quality necessary for the operation of fuel cells; according to ISO 14687-2, the purity of hydrogen must be at least 99,97 %.
Hydrogen filter – a device for removing mechanical impurities from compressed hydrogen.
Compressive strength test – A procedure to verify that the equipment under test meets the mechanical strength requirements.
Explosive atmosphere – A mixture of air with combustible substances, e.g. hydrogen, in the form of gases, vapours, mists or dusts at atmospheric conditions ranging from the lower explosive limit (LEL) to the upper explosive limit (UEL) at which, after initiation, combustion extends to the volume of the entire unburned mixture.
Dispenser – a dispensing device that does not meet the definition of a dispenser, but which performs a function for dispensing compressed hydrogen in specific conditions (in-house facilities, small filling stations, development filling stations and other facilities for which this solution is appropriate).
Dispensing rack – a compressed hydrogen dispensing device which does not need to be opened for operation and which is equipped with a specified gauge for measuring the quantity of hydrogen dispensed for commercial purposes (in kilograms) and a control and safety device to ensure that the prescribed filling conditions are met.
Dispensing equipment – equipment for the dispensing and measuring of the quantity of compressed hydrogen removed; these are dispensing racks and dispensing devices.
High-pressure storage tank – a device used to store compressed hydrogen for rapid filling of one or more mobile devices simultaneously while reducing the number of compressor starts.
Safety device – A device to protect against a hazardous situation that automatically causes the filling of a mobile device to be interrupted if hydrogen leaks or the filling hose is broken.
Hydrogen refrigeration device – a device that cools hydrogen; it is located downstream of the compressor discharge.