Safety Instructions interpret, in general, existing Safety Codes published in the old classification. These Safety Intructions remain temporarily in force, until their revision or transcription into the new rules.

IS 4 Rev. - Safety inspections (2006) en fr
Definition of responsibilities and organizational aspects concerning safety inspections, with emphasis for buildings.

IS 5 - Emergency stops (2001) en fr
Description of the two types of emergency stops (general and local emergency stops), definition of the buildings or areas to be equipped, and effects due to these emergency stops on power supplies or accelerators. Exceptions and rules for safety equipment.

IS 7 - Individual protection (1993) en fr
This instruction is based on the European Directive 89/656/CEE concerning minimal safety and health requirements for the use of individual protective equipment when hazards cannot be prevented or adequately limited by collective technical protective measures.
Concerning chemical individual protection, refer to the set of Chemical Safety rules which cancel and replace the corresponding provisions within this Safety Instruction IS 7.

IS 22 - Rules for the safe use of lasers at CERN (1994) en fr
The radiation produced by lasers may be hazardous to the human eye and skin. It may also present fire or explosion risks. Lasers have been classified according to their exposure hazards. Conditions for use and warning labels and notices are recorded.

IS 23 - Criteria and Standard Test Methods for the Selection of Electric Cables and Wires with Respect to Fire Safety and Radiation Resistance (2005) en fr
This instruction is based on the latest standards and recommendations to ensure a very high level of safety against hazards associated with smoke, toxicity and corrosivity from burning plastics. It summarizes the required properties for the different materials and cable types and is applicable to all types of cables and wires and other insulated parts to be used in CERN installations.

IS 24 - Regulations applicable to electrical installations (1990) en fr
Reference is made to publications on electrical installations.

IS 25 - Beryllium (Obsolete)

IS 32 - Polychlorinated biphenyls (PCB) (1986) en fr
Rules for the safe use of PCB and for the elimination from CERN in a controlled and safe manner, to conform to the legislation of the Host-States.

IS 33 - Voltage domains according to IEC (1999) en fr
Classification of electrical installations according to the voltage value: Extra Low Voltage (E.L.V.), Low Voltage (L.V.), High Voltage (H.V.).

IS 34 - Glass windows (1988) en fr
This applies to any type of glass-ware loaded by a differential pressure. Design rules, testing and acceptance procedures by the Mechanical Section of SC are recalled.
(refer also to Safety Regulation SR-M).

IS 36 - Safety Rules for the Use of Static Magnetic Fields at CERN (2005) en fr
Studies on workers exposed to static magnetic fields have indicated various subjective symptoms and functional disturbances. This instruction recalls some of the technical hazards encountered, and informs on exposure limits and on the safety procedures for operating magnets.

IS 37 - Alarms and alarm systems (2003) en fr
The object is to define safety alarms and to establish general rules for the installation, maintenance, disabling, and layout of safety alarm systems generating level 3 alarms. The EDH version of the disabling form is now mandatory.

IS 38 - The use of flammable gases in underground physics experiments at CERN (Obsolete)

IS 39 - Notice of Start of Works (Avis d'ouverture de chantier) (2000) en fr
Work performed by firms (civil engineering or installation of infrastructure or equipment) on the CERN site shall be contingent on a "Notice of Start of Works" drawn up by the works supervisor before the work starts. The aim is to draw attention to the risks and problems caused in the surroundings by the work, and to ensure a good collaboration between the firms and all services affected.

IS 41 - The use of plastic and other non-metallic materials at CERN with respect to fire safety and radiation resistance (2005) en fr
This instruction is intended to ensure a very high level of safety and must be applied to all new installations at CERN, including modifications to existing installations. CERN attaches great importance to the hazards associated with the density, toxicity and corrosiveness of smoke from burning plastics. The document is complemented by tables of standards and specifications for the selection of plastics, and guidelines for their use.

IS 42 - Compressed gas bottles (1995) en fr
Safety rules for the transport, use and storing of cylinders to avoid fire or explosion hazards.

IS 43 - Asbestos - Dangers and precautions (2003) en fr
The purpose of this Safety Instruction is to remind the CERN personnel of the safety instructions prohibiting the use of asbestos, of those concerning the management of asbestos in situ and those governing activities entailing a risk of exposure to asbestos./p>

IS 44 - Visits to CERN's installations (1998) en fr
This intruction applies to visits organized by the Visits Service r by experiment collaborations, as well as toprofessional or private visits. It specifies the number of visitors per guide (appointed by the Visits Service) or other persons in charge (escort) and informs of certain conditions (i.e. smoking forbidden, strong magnetic fields, approved itinerary) or of possible difficulties for participants handicapped or claustrophobic. Specific rules are drawn up for visits in underground structures.

IS 47 - The use of cryogenics fluids (1998) en fr
The cooling and operation of superconducting RF cavities and magnetsystems for particle accelerators and magnets for detectors demande large quantities of cryogenic fluids. These fluids may generate health hazards for cryogenic personnel (asphyxiation, burns, etc.). A number of precautions or measures must be taken toprevent accidents and injuries, for instance: protective clothing, vent lines, alarm and shutdown systems or pressure relief devices.

IS 48 - Fire prevention for cables, cable trays and conduits (2001) en fr
This Safety Instruction defines rules and other preventive measures for cable fires. It lists the most common fire risks for cables and conduits. Mandatory precautions are specifically aimed at preventing cable fires in physics experiments where confined spaces, higher vicinity risks and lack of effective electrical protections add up to an increased risk of ignition.

IS 49 - Avoiding chemical pollution of water(2002) en fr
This instruction gives a definition of chemical pollution and examples of common water pollution hazard. It explains the role of the SC services in matters of the environmental protection, lists the activities and circumstances that may lead to pollution. It outlines practical measures to be obeyed to prevent pollution and instructs how to behave when pollution or leakage of polluting liquids is observed or believed. Finally, it explains legal aspects of water pollution, including INB regulations, and addresses liaisons with the Host States in matters of environmental protection.

IS 50 - Safety Coordination on CERN Worksites (2004) en fr
Workers employed by different Employers may share the same worksites. In the course of executing their own work, employees may find themselves in the presence of activities unrelated to their own. Such co-activities have to be well coordinated in order to guarantee safe working conditions. This is the object of "safety coordination".

IS 51 - Operational and Information Procedures in Reponse to Accidents (2005) en fr
The scope of this Safety Instruction is to describe operational procedures in response to accidents, to assure coordination of interventions, both at CERN and with outside emergency services as well as the transmission of information within CERN and in case of need to the Host States Authorities and media. The adopted procedures depend on the seriousness level assigned to the event.

Safety rules are also classified by domains (Safety rules by domains).