CEN/TC 186 - Industrial thermoprocessing - Safety

This document specifies the safety requirements for combustion and fuel handling systems that are part of industrial furnaces and associated processing equipment (TPE), including single and multiple burner systems in thermoprocessing equipment and machines.
NOTE            The general safety requirements common to TPE are provided in ISO 13577-1:2016. ISO 13577-1:2016, Annex B also includes a list of processes for which industrial furnaces and heating systems covered by the ISO 13577 series are used.
This document deals with significant hazards, hazardous situations and events relevant to combustion and fuel handling systems as listed in Annex A, when used as intended and under the conditions for use as described in the instruction handbook.
This document covers:
—     fuel pipework downstream of and including the manual isolating valve;
—     combustion air supply (including oxygen and oxygen enriched combustion air) and flue gas system;
—     burner(s), burner system and ignition device;
—     functional requirements for safety related control system.
This document applies to any oxidation of gaseous and liquid fuels with air or other gases containing free oxygen to release thermal energy in TPE. Annex B includes examples of gaseous and liquid fuels.
For thermal or catalytic post combustion and waste incineration, this document applies only to auxiliary burners designed to start-up and/or support the process.
The pressure hazard of the piping and components covered by this document is within the maximum pressure/size relationship of category I as specified in Annex C.
This document also gives the necessary requirements regarding information for use.
This document does not cover hazards from heating generated by electricity.
This document does not deal with the hazards created by the release of flammable substances from the products processed in the TPE.
This document is not applicable to combustion and fuel handling systems:
—     of gas welding and allied processes;
—     up-stream of the TPE manual isolating valve.
This document is not applicable to industrial furnaces and associated processing equipment (TPE), including single and multiple burner systems in thermoprocessing equipment and machines manufactured before the date of its publication.
This document is not applicable to blast furnaces, converters (in steel plants), boilers, fired heaters (including reformer furnaces) in the petrochemical and chemical industries.
This document is not applicable to electrical cabling and power cabling upstream of the TPE control panel/protective system.

This document specifies the requirements for protective systems used in industrial furnaces and associated processing equipment (TPE).
The functional requirements to which the protective systems apply are specified in ISO 13577-1 ISO 13577-2 and ISO 13577-3.
This document is not applicable to blast furnaces, converters (in steel plants), boilers, fired heaters (including reformer furnaces) in the petrochemical and chemical industries.
This document is not applicable to electrical cabling and power cabling upstream of the TPE control panel/protective system.
This document is not applicable to the protective systems manufactured before the date of its publication.

This part of the EN 746 series specifies safety requirements for generation and use of protective and reactive atmosphere gases that are part of industrial thermo-processing equipment (TPE).
The general safety requirements common to TPE are provided in EN 746 1:1997+A1:2009 (see Introduction).
This part of the EN 746 series deals with significant hazards, hazardous situations and events relevant to the generation and use of protective and reactive atmosphere gases created by thermochemical reactions and their use in TPE that are part of TPE as listed in Clause 4 and Clause 5, when used as intended and under the conditions foreseen by the manufacturer.
This part of the EN 746 series covers:
-   pipework downstream of and including the manual isolating valve,
-   equipment for the generation of atmosphere gases,
-   additional equipment for the use of atmosphere gases in TPE,
-   safety devices, and
-   functional requirements for safety related control system
for the generation and use of protective and reactive atmosphere gases.
It applies to the supply of atmosphere gas, source gas, inert gas and process liquids to TPE and their removal from TPE, confined to equipment integrated in the TPE.
This part of the EN 746 series also details the anticipated significant hazards associated with atmosphere gas systems and their use in TPE and specifies the appropriate preventative measures for the reduction or elimination of these hazards.
The pressure hazard of the piping and components covered by this standard is within the maximum pressure/size relationship of group 1 as described in Annex C.
This part of the EN 746 series:
-   specifies the requirements to be met to ensure the safety of persons and property during installation, commissioning, start up, operation, shutdown and maintenance,
-   does not cover the relevant risks involved in the flue gas ducting system when it is not considered a part of TPE,
-   is not applicable to utility supply upstream of the TPE main disconnects,
-   does not apply to TPE for semi-conductor devices,
-   does not apply to TPE with atmosphere, such as air and flue gas from an over stoichiometric combustion,
-   does not cover the decommissioning of the TPE,
-   does not cover vacuum furnaces,
-   does not cover blast furnaces, converters (in steel plants), boilers and equipment not covered under EN ISO 12100:2010.
-   does not deal with the hazard of noise which is covered in EN 746 1:1997+A1:2009,
-   is not applicable to generation and use of atmosphere gas in TPE and associated plant which is manufactured before the date of its publication, and
-   gives the necessary requirements for the information for use.
A TPE designed according to this part of EN 746 series does not create any potentially explosive atmosphere in the area around the TPE and is not designed to be located in an area with a potentially explosive or hazardous atmosphere.
This part of the EN 746 series deals with significant hazards which are described in Annex A.
A table of typical protective and reactive gases is given in Annex B.

1.1   This part of EN 746 specifies common safety requirements for industrial thermoprocessing equipment (for example industrial furnaces and industrial heating equipment), which meets the definition for machinery given in EN ISO 12100-1:2003.
It details the anticipated significant hazards associated with industrial thermoprocessing equipment and specifies the appropriate preventative measures for reduction or elimination of these hazards.
This standard gives general principles and common requirements for the reduction of risks for equipments covered by the scope.
The common requirements apply to all of the subsequent parts of this EN 746 dealing with specific equipment unless an exception is stated in the relevant Part. The general principles (subclauses are pointed out) will be used to establish the specific technical measures in the subsequent Part(s) dealing with safety requirements for particular equipment.
NOTE   For similar equipment not covered by the particular Parts of this standard, EN 746-1 can be used to assist in the reduction of risk for the Hazards identified in clause 4 (List of Hazards).
1.2   This part of EN 746 is applicable to industrial thermoprocessing equipments for use in fields such as:
-   Metallurgical and metal working plant;
-   Glass making plant;
-   Ceramic manufacturing plant;
-   Cement, lime and gypsum manufacturing plant;
-   Chemical plant;
-   Waste incineration equipment;
And heated by:
-   Gaseous fuels;
-   Liquid fuels;
-   Solid fuels;
-   Mixed fuels;
-   Electricity.
The thermoprocessing equipment covered by this Part of EN 746 is further specified in clause 3.
A more detailed list of thermoprocessing equipment within these categories is given in Annex A.
In the remainder of this standard the expression "equipment" will be used.
This Part of EN 746 is not applicable to blast furnaces, converters (in steel plants), boilers, welding machines or food processing equipment.
1.3   This Part of EN 746 specifies the requirements to be

This noise test code specifies all the information necessary to carry out efficiently and under standardized conditions the determination, declaration and verification of the noise emission characteristics of industrial thermoprocessing equipment as described especially in EN 746-1, EN 746-2 and EN 746-3. It also indicates the location of work stations where measurements need to be made.
Noise emission characteristics include emission sound pressure levels at work stations and the sound power level. The determination of these quantities is necessary for:
-   manufacturers to declare the noise emitted;
-   comparing the noise emitted by machines in the group concerned;
-   purposes of noise control at the source at the design stage.
The use of this standard ensures the reproducibility of the determination of the noise emission characteristics within specified limits determined by the grade of accuracy of the basic noise measurement method used. Noise measurement methods allowed by this standard are engineering methods (grade 2) and survey methods (grade 3).
This standard does not cover the computation of personnel daily noise exposure.

This part of EN 746 gives the specific hazards and safety requirements that shall be provided by the manufacturer for Quenching Equipment, whether it is used as an independent unit or an integrated part of a plant. This part of EN 746 does not cover specific hazards and safety requirements for Salt Bath bath equipment used as a quenching means (see prEN 746-5:1999). This part of EN 746 does not cover the handling, storage, transport, disposal, transfer or regeneration of the quenching media and processed material outside the limits of the equipment.

This part of EN 746 gives the specific hazards and safety requirements for the melting and use of molten salt that shall be provided by the manufacturer for Salt Bath Industrial Thermoprocessing Equipment, whether it is used as an independent unit or an integrated part of a plant. The limits of the equipment will include any transportation equipment which is located wholly or partially in the bath. This part of EN 746 does not cover the handling, storage, transport disposal, transfer or regeneration of the salts and processed material outside the limits of the equipment.

This part of EN 746 gives the specific hazards and safety requirements that shall be provided by the manufacturer for Hot Dip Industrial Batch and the Bath of Continuous Galvanising Thermoprocessing Equipment, whether it is used as an independent unit or an integrated part of a plant. This part of EN 746 does not cover the handling, storage, transport, disposal, transfer or regeneration of the zinc and the processed material outside the limits of the equipment. This part of EN 746 does not deal with the risks arising from any component handling equipment for the dip process or for the associated protective measures

This document specifies the general safety requirements common to industrial furnaces and associated processing equipment (TPE).
This document deals with the significant hazards, hazardous situations or hazardous events relevant to TPE, as listed in Annex A, when TPE is used as intended and also under conditions of misuse that are reasonably foreseeable by the manufacturer.
This document specifies the requirements intended to be met by the manufacturer to ensure the safety of persons and property during commissioning, start-up, operation, shut-down, maintenance periods and dismantling, as well as in the event of foreseeable faults or malfunctions that can occur in the equipment.
These general safety requirements apply to all TPE, unless an exception is given in other parts of EN°746 dealing with specific equipment. The provisions of other parts of EN°746 that directly apply to specific types of TPE take precedence over the provisions of this document.
This document is not applicable to blast furnaces, converters (in steel plants), boilers, fired heaters (including reformer furnaces or cracking furnaces) in the petrochemical and chemical industries or equipment not covered under EN°ISO°12100.
This document or parts of this document can be used to blast furnaces, converters (in steel plants), boilers, fired heaters (including reformer furnaces or cracking furnaces) in the petrochemical and chemical industries or equipment not covered under EN°ISO°12100

This part of EN 746 specifies the safety requirements for combustion and fuel handling systems that are part of industrial furnaces and associated processing equipment (TPE).
NOTE   The general safety requirements common to TPE are provided in prEN 746 1:2020 (See introduction).
This part of EN 746 deals with significant hazards, hazardous situations and events relevant to combustion and fuel handling systems as listed in Annex A, when used as intended and under the conditions foreseen by the manufacturer.
This part of EN 746 covers:
-   fuel pipework downstream of and including the manual isolating valve;
-   combustion air supply (including oxygen and oxygen enriched combustion air) and flue gas system;
-   burner(s), burner system and ignition device;
-   functional requirements for safety related control system.
This part of EN 746 applies to any oxidation with air or other gases containing free oxygen of gaseous and liquid fuels or any combustion of them to release thermal energy in TPE.
For thermal or catalytic post combustion and waste incineration, this part of EN 746 applies only to auxiliary burners designed to start-up and/or support the process.
The pressure hazard of the piping and components covered by this part of EN 746 is within the maximum pressure/size relationship of category I as described in normative Annex E.
This part of EN 746 also gives the necessary requirements regarding information for use.
This part of EN 746 does not cover hazards from heating generated by electricity.
This part of EN 746 does not deal with the hazards created by the release of flammable substances from the products processed in the TPE.
This part of EN 746 is not applicable to combustion and fuel handling systems:
-   of gas welding and allied processes;
-   up-stream of the TPE manual isolating valve.
This part of EN 746 is not applicable to electrical cabling and power cabling upstream of the TPE control panel/protective system.

This part of EN 746 specifies the requirements for protective systems used in industrial furnaces and associated processing equipment (TPE).
The functional requirements to which the protective systems apply are specified in the other parts of the EN 746 series.

This part of EN 746 together with EN 746-1 specifies safety requirements for single and multiple burners that are part of Industrial Thermoprocessing Equipment. (In this standard referred to as IThE).
This document deals with significant hazards, hazardous situations and events relevant to combustion and fuel handling systems that are part of IThE as listed in Clause 4, when used as intended and under the conditions foreseen by the manufacturer.
This European Standard covers:
- fuel pipework downstream of and including the manual isolating valve;
- burner(s), burner system and ignition device;
- safety related control system (protective system).
This European Standard applies to any oxidation with air or other gases containing free oxygen of gaseous, liquid and solid fuels or any combustion of them to release thermal energy.
For thermal or catalytic post combustion and waste incineration, this European Standard applies only to auxiliary burners designed to start-up and/or support the process.
The pressure hazard of the piping and components covered by this standard is within the maximum pressure/size relationship of category I as described in normative Annex D.
This European Standard also gives the necessary requirements for the information for use.
This European Standard does not cover hazards from heating generated by electricity.
This European Standard does not deal with the hazards created by the release of flammable substances from the products processed in the IThE.
NOTE EN 1539, Dryers and ovens, in which flammable substances are released — Safety requirements
This European Standard is not applicable to combustion and fuel handling systems
- of welding and soldering machines;
- up-stream of the IThE manual isolating valve.
This European Standard is not applicable to electricity cabling and power cabling upstream of the IThE control panel/protective system.
Noise can be a significant hazard for combustion and fuel handling systems.

This part of EN 746 specifies safety requirements for atmosphere gas systems and their use in industrial thermo-processing equipment and associated plant, including systems for the production of atmosphere gases by reaction inside the thermo-processing equipment.
It applies to the supply of atmosphere gases, gaseous and liquid additions to, and their removal from industrial thermo-processing equipment and associated plant, confined to equipment integrated in the thermo-processing and associated plant.
This part of EN 746 also details the anticipated significant hazards associated with atmosphere gas systems and their use in industrial thermo-processing equipment and specifies the appropriate preventative measures for the reduction or elimination of these hazards.
This part of EN 746 does not apply to atmosphere process gases, essential safety equipment, start-up, operation and shut-down of thermo-processing plant for semi-conductor devices for which special additional engineering requirements are necessary.
This part of EN 746 specifies the requirements to be met to ensure the safety of persons and property during commissioning, start up, operation, shut down and maintenance, as well as in the event of foreseeable faults or malfunctions which can occur in the equipment. It specifies the safety requirements at stages in the life of the equipment, and its design, ordering, construction and use.
This part of EN 746 applies to equipment which is placed on the market after the date of issue of this standard.
The hazards covered by this Part of EN 746 are listed in clause 4.
A table of typical atmosphere gases is given in Annex A.

This Part of EN 746 applies to all combustion and fuel handling equipment used in industrial thermoprocessing equipment which meets the definition for machinery given in 3.1 of EN 292-1:1991, referred to hereafter as "equipment", e.g. furnaces, kilns, ovens, heating systems such as salt baths and melting tanks, and equipment such as integrated burners and torches used in casting machines, ladle heating etc.  It applies to the handling of fuel immediately adjacent to the equipment but downstream of and including the main plant manually operated fuel shut off valve. It specifies the list of hazards, the safety requirements and associated measures as well as the user instructions relating to fuel handling and combustion equipment.  It applies to all forms of gaseous, liquid and solid fuel and any combinations of them in combustion with air or other gas containing free oxygen.  This Part of EN 746 also applies to gas torches, work station burners, working flame burners and other burners not integral with the plant, even though they are not covered by the mandate.  This Part of EN 746 specifies the requirements to be met by the manufacturer to ensure the safety of persons and property during commissioning, start-up, operation, shut-down and maintenance, as well as in the event of foreseeable faults or malfunctions. It specifies the safety requirements at stages in the life of the equipment, and its design, ordering, construction and use.   The hazards covered by this Part of EN 746 are listed in clause 4.  This Part of EN 746 applies to equipment which is placed on the market after the date of issue of this standard.  This Part of EN 746 does not apply to but may be used as reference for:    - gas torches for welding, flame cutting and related processes; - boiler installations; - environmental space heating of any kind; - the storage of fuel; - industrial food processing.

1.1 This part of prEN 746 specifies common safety requirements for industrial thermoprocessing equipment (for example industrial furnaces and industrial heating equipment), which meets the definition for machinery given in EN 292-1:1991. It details the anticipated significant hazards associated with industrial thermoprocessing equipment and specifies the appropriate preventative measures for reduction or elimination of these hazards. This standard gives general principles and common requirements for the reduction of risks for equipments covered by the scope.

This standard specifies the means to determine, declare and verify the noise emission characteristics of the industrial thermoprocessing equipment detailed in clause 4. These means cover any ancillary equipment which forms an integral part of the equipment supplied at the same time (eg charging, discharging and process handling units). This noise test code also gives requirements for installation and operating conditions for the equipment within the scope of thisStandard. It also indicates the location of work stations where measurements shall be made.

This Part of EN 746 specifies safety requirements for atmosphere gas systems and their use in industrial thermo-processing equipment and associated plant, including systems for the production of atmosphere gases by reaction inside the thermo-processing equipment.  It applies to the supply of atmosphere gases, gaseous and liquid additions to, and their removal from industrial thermo-processing equipment and associated plant, confined to equipment integrated in the thermo-processing and associated plant.  This Part of EN 746 also details the anticipated significant hazards associated with atmosphere gas systems and their use in industrial thermo-processing equipment and specifies the appropriate preventative measures for the reduction or elimination of these hazards.  This Part of EN 746 does not apply to atmosphere process gases, essential safety equipment, start-up, operation and shut-down of thermo-processing plant for semi-conductor devices for which special additional engineering requirements are necessary.  This Part of EN 746 specifies the requirements to be met to ensure the safety of persons and property during commissioning, start up, operation, shut down and maintenance, as well as in the event of foreseeable faults or malfunctions which can occur in the equipment. It specifies the safety requirements at stages in the life of the equipment, and its design, ordering, construction and use.  This Part of EN 746 applies to equipment which is placed on the market after the date of issue of this standard.  The hazards covered by this Part of EN 746 are listed in clause 4.  A table of typical atmosphere gases is given in Annex A.