NR35 – Working at Height

(MTE Ordinance No. 3903 of December 28th, 2023)

35.1 Objective
35.2 Scope
35.3 Responsibilities
35.4 Authorization, Qualification and Fitness to Work
35.5 Planning and Organisation
35.6 Fall Protection System (FPS)
35.7 Emergency and Rescue
Annex I – Rope Access
Annex II – Anchor System

35.1 Objective

35.1.1 This standard sets out the requirements and preventive measures for work at height, including planning, organisation and execution, to ensure the safety and health of workers directly or indirectly involved in this activity.

35.2 Scope

35.2.1 The provisions of this standard apply to any activity where there is a difference in level of more than 2.0 metres (two metres) from the lower level where there is a risk of a fall.

35.3. Responsibilities

35.3.1 It’s the responsibility of the organisation to:

a) ensure the implementation of the prevention measures specified in this NR;

b) ensure that the risk analysis (RA) is conducted and, where appropriate, the Permit to Work (PTW) is issued;

c) prepare operating procedures for routine work at height activities;

d) make safety instructions included in the risk analysis, permit to work and operating procedures available to all members of the work team through the organisation’s means of communication that are easily accessible to the worker;

e) ensure that a preliminary assessment of the conditions for working at a height is carried out by studying, planning and implementing the measures and additional safety measures to be applied;

f) take the necessary measures to monitor compliance by service providers with the prevention measures set out in this standard;

g) ensure that no work at height starts until the preventive measures defined in this NR have been adopted;

h) ensure that work at height is suspended when an unforeseen hazardous situation or condition arises which cannot be immediately eliminated or controlled;

i) establish a system for authorising workers to work at height; and

j) ensure that the documentation provided for in this NR is organised and retained for a minimum period of 5 (five) years, unless specifically provided for in another NR.

35.3.2 It is the worker’s responsibility to comply with the provisions of this standard and item 1.4.2 of NR-01 – General Provisions and Occupational Risk Management, and the operating procedures issued by the employer.

35.4. Authorization, Qualification and Fitness to Work

35.4.1 All work at height shall be carried out by a worker formally authorised by the organisation. A worker authorised to work at height is considered to be a qualified worker whose medical condition has been assessed and found to be fit for the work. Authorisation to work at height shall take account of:

a) the activities to be carried out by the worker;

b) the qualifications the worker has achieved; and

c) the medical fitness to carry out the activties. Authorisation shall be recorded in the worker’s employment records. The organisation shall establish an identification system that allows the scope of each worker’s authorisation to be known at all times.

35.4.2 Workers are considered qualified to work at height if they have undergone and passed the training process, which includes initial, periodic and occasional theoretical and practical training, in accordance with the provisions of NR-01. Initial training of at least 8 (eight) hours shall be given before the worker starts work and shall cover:

a) the rules and regulations applicable to work at height;

b) risk analysis and impeding conditions;

c) potential risks associated with work at a height and prevention and control measures;

d) collective protective systems, equipment and procedures;

e) PPE for work at height: selection, inspection, maintenance and limitation of use;

f) typical incidents involving work at height; and

g) emergency procedures, including the basics of rescue techniques and first aid. Periodic training shall be carried out every two years, with a minimum duration of eight hours, according to the programme defined by the employer.

35.4.3 The training shall be given by instructors with proven competence in the subject, under the responsibility of a qualified or legally qualified safety professional.

35.4.4 It is the responsibility of the organisation to assess the medical condition of employees working at heights in accordance with NR-07, in particular item 7.5.3, taking into account pathologies that could lead to sudden illness and falls from heights, as well as psychosocial factors. Fitness to work at heights shall be stated in the worker’s occupational health certificate.

35.5. Planning and Organisation

35.5.1 All work at height shall be planned and organised.

35.5.2 When planning work, the following hierarchy shall be adopted:

a) measures to avoid work at height whenever there is an alternative means of carrying out the work;

b) measures to eliminate the risk of workers falling where it is impossible to carry out the work in any other way; and

c) measures to minimise the consequences of falls where the risk of falls cannot be eliminated.

35.5.3 All work at a height shall be carried out under supervision, the form of which shall be determined by the risk analysis in accordance with the characteristics of the activity.

35.5.4 The work shall take account of external influences which may alter the conditions of the work place already provided for in the risk analysis.

35.5.5 All work at height shall be preceded by a risk analysis. In addition to the risks inherent in working at height, the risk analysis shall consider:

a) the place where the work is to be carried out and its surroundings;

b) isolating and marking of work area;

c) the provision of anchorage systems and anchor points;

d) adverse weather conditions;

e) the selection, testing, use and limitation of collective and personal protective systems, taking account of the technical standards in force, the manufacturer’s or designer’s guidelines and the principles of reducing impact and fall factors;

f) the risk of materials and tools falling;

g) concurrent works involving specific risks;

h) compliance with health and safety requirements set out in other regulatory standards;

i) additional risks;

j) obstructive conditions;

k) emergency situations and the planning of rescue and first aid, in order to reduce the worker’s inert suspension time;

l) the need for a communication system; and

m) the form of supervision.

35.5.6 A risk analysis may be included in the relevant operating procedure for routine work at height activities. Operating procedures for routine work at height activities shall include:

a) the details of the task;

b) the preventive measures characteristic of the routine;

c) obstructive conditions;

d) the required collective and individual protection systems; and

e) competencies and responsibilities.

35.5.7 Non-routine work at heights shall be authorized in advance by a permit to work. For non-routine activities, the preventive measures shall be specified in the risk analysis and the permit to work.

35.5.8 The permit to work shall be issued in physical or digital form, approved by the person responsible for authorizing the work, accessible at the place where the work is carried out and, at the end, closed and filed in such a way that it can be traced. The permit-to-work shall include:

a) minimum requirements to be met for the performance of the work;

b) the provisions and measures identified in the risk assessment; and

c) a list of all persons involved in the activity. The permit-to-work shall be valid for the duration of the activity, limited to the shift or working day, and may be revalidated by the person responsible for the permit in situations where there is no change in the conditions established or in the work team.

35.6  Fall Protection System (FPS)

35.6.1 The use of an FPS is mandatory whenever work at height cannot be avoided.

35.6.2 The FPS shall:

a) be suitable for the task to be performed;

b) be selected in accordance with the risk analysis;

c) be selected by a qualified or legally qualified occupational safety professional;

d) be strong enough to withstand the maximum applicable force expected in the event of a fall;

e) comply with national technical standards or, in the absence of such standards, with the applicable international standards at the time of their manufacture or construction; and

f) have all its components compatible and subject to systematic inspection.

35.6.3 The selection of the FPS shall take account of the use of:

a) collective fall protection system (CFPS); or

b) personal fall protection system (PFPS), in the following situations:

I – when it is impossible to use the CFPS;

II – when the CFPS does not provide complete protection against the risk of falls; or

III – to deal with emergency situations. The CFPS shall be designed by a legally qualified professional.

35.6.4 The PFPS may be for travel restriction, fall arrest, work positioning or rope access.

35.6.5 The manufacturer or importer of personal protective equipment (PPE) shall provide information on the performance of the equipment and the limits of its use, taking into account the total weight applied to the system (worker and equipment) and the other aspects referred to in 35.6.11.

35.6.6 Initial, routine and periodic inspections of the PFPS shall be carried out in accordance with the manufacturer’s or designer’s recommendations and any elements showing defects or deformations shall be rejected. The initial inspection is the inspection performed between receipt and first use of the PFPS. Routine inspections are those carried out before work commences. The periodic inspection shall be carried out at least once every 12 months, although the interval between inspections may be reduced depending on the type of use, frequency of use or exposure to aggressive agents. Initial inspections, periodic inspections and routine inspections in which the elements of the PFPS are rejected shall be recorded. Elements of the PFPS that show defects, deterioration, deformation or have been affected by falls must be rendered unusable and discarded, unless their restoration is provided for by national technical standards or, in the absence of such standards, by international standards and in accordance with the manufacturer’s recommendations.

35.6.7 The PFPS shall be selected so that the impact force transmitted to the worker in the event of a fall does not exceed 6 kN.

35.6.8 Anchor systems designed to restrict movement shall be sized to withstand the forces likely to be applied. If there is a possibility of a fall to a lower level, the system shall be designed as a fall arrest system in accordance with the risk assessment.

35.6.9 In the PFPS for fall arrest and rope access, the personal protective equipment shall be a full body harness. The full body harness, when used for fall arrest, shall be attached by the fall arrest attachment specified by the manufacturer. The full body harness, when used for fall arrest, shall be fitted with an energy absorbing lanyard.

35.6.10 The use of the sliding-type fall arrester system shall be in accordance with the manufacturer’s recommendations, in particular with regard to:

a) the compatibility of the sliding-type fall arrester with the vertical lifeline; and

b) the maximum length of the connectors.

35.6.11 The risk analysis required by this standard shall consider the following aspects for the PFPS:

a) the need for the worker to remain attached to the system throughout the period of exposure to the risk of falling;

b) free fall distance;

c) fall factor;

d) the use of a connector that ensures that no more than 6 kN of impact is transmitted to the worker when a fall is arrested;

e) free fall zone; and

f) the compatibility of the elements of the PFPS. The lanyard and fall arrester shall be positioned:

a) to limit the free fall distance; and

b) so that, in the event of a fall, the worker will not collide with a lower structure. The lanyard shall not be used, except as specified by the manufacturer and taking into account its limitations of use, either:

a) connected to another lanyard or connector; or

b) with knots or loops.

35.7. Emergency and Rescue

35.7.1 The organization shall establish, implement and maintain procedures for responding to work-at-height emergencies which, in addition to the provisions of NR-01, take into account:

a) the hazards associated with the rescue operation;

b) the necessary emergency response and rescue team and its size;

c) the estimated rescue time; and

d) the appropriate techniques, specific personal and/or collective equipment and rescue systems available to reduce the worker’s inert suspension time and exposure to existing hazards. The organization shall carry out a risk analysis of the identified work-at-height emergency scenarios.

35.7.2 The organisation shall ensure that the team has the necessary resources to respond to emergencies.

35.7.3 Those responsible for carrying out rescue operations shall be trained to carry out such operations and provide first aid, and shall have the physical and mental fitness compatible with the activity to be carried out. If carried out by an internal team, the organization shall determine the content and workload of the training according to the emergency scenarios.


Energy abosorver: An element whose function is to limit the impact force transmitted to the worker by dissipating kinetic energy.

Risk analysis: Assessment of potential hazards, their causes, consequences and control measures.

Structural anchor: An element permanently attached to the structure to which a lifeline or PPE can be attached.

Routine activities: Usual activities, regardless of frequency, that are part of the organization’s work process.

Conformity assessment: Demonstration that the requirements specified in a technical standard for a product, process, system or person are met.

Preliminary assessment: An assessment, not necessarily in written form, carried out in the workplace to identify and anticipate undesirable events and accidents that cannot be foreseen in the risk analyses carried out or that are not considered in the procedures due to specific situations that are not normal or foreseeable.

Certification: Attestation by a conformity assessment body of products, processes, systems or people that compliance with the requirements specified in a technical standard has been demonstrated.

Certified: Having undergone certification.

Full body harness: Personal protective equipment used for work at a height where there is a risk of falling, consisting of a device attached to the body and designed to absorb and distribute the forces of a fall on at least the thighs, pelvis, chest and torso.

Impeding conditions: situations that prevent the execution or continuity of work, which may put the health or physical integrity of the worker at risk.

Anchor device: A device removable from the structure and designed for use as part of a personal fall protection system, the elements of which include one or more fixed or movable attachment points.

Stopping distance: The distance travelled during the application of the energy absorption system, normally between the start of stopping and the end of the fall.

Free fall distance: The distance from the start of the fall and the onset of the arresting force.

Attachment element: Element of a safety harness for connecting a connecting element.

Fall arreset attachment: Attachment element designed to withstand the impact force of a fall arrest device located in the dorsal or pectoral region.

Fixing: element designed to attach components of the anchor system.

Connecting element: Element with the function of connecting the safety harness to the anchorage system, and may incorporate an energy absorber.

Accessory equipment: Equipment used in rope access work that complements the full body harness, lanyard, fall arrester and rope, such as: connectors, blockers, webbing slings, pulleys, descenders, ascenders, etc.

Stairs for collective use: These are used as a means of access and circulation in the workplaces of buildings, industrial and floating structures, as well as in emergency situations.

Structure: Artificial or natural structure used to integrate the anchor system, capable of withstanding the forces of the system.

Connector: A component or connecting element of a fall arrest system.

Fall factor: The ratio of the distance the worker would travel in a fall to the length of the equipment that would stop them.

Impact force: Dynamic force generated by the deceleration of a worker during fall arrest.

Maximum applicable force: The maximum force that can be applied to an element of an anchor system.

Initial inspection: Performed between receipt and first use of the PFPS component to ensure that it is suitable for its intended use, functions correctly, meets regulatory requirements and is in good condition.

Periodic inspection: Performed periodically and characterized by an examination of the equipment, component or system to detect its defects, damage or wear, in accordance with the designer’s or manufacturer’s instructions, with a periodicity not to exceed 12 months.

Routine inspection: Always performed before work begins, both visually and tactilely, by the worker before using the equipment that makes up the PFPS.

External influences: Variables that must be taken into account when determining and selecting personal safety measures and that cannot be controlled in advance.

Supervised operation: An activity performed under the continuous supervision of a professional with the knowledge to assess the risks of the activity and to implement measures to control, minimize, or neutralize those risks.

Permit to Work (PTW): Written document containing a set of control measures aimed at carrying out safe work, as well as emergency and rescue measures.

Anchor point: An integral part of an anchor system to which personal protective equipment is attached.

Proficiency: Competence, aptitude, training and skill combined with professional experience as evidenced by diplomas, employment records, specific contracts in the field, or other documentation.

Note: Demonstrated proficiency in the subject matter does not mean training in a specific course, but rather skills, experience and knowledge sufficient to teach the topics covered in the training. However, the training must be conducted under the responsibility of a qualified safety professional.

Legally qualified professional: worker previously qualified and registered to competent professional council.

Designer: Legally qualified professional responsible for designing projects according to the responsibilities of the respective class council.

Additional risks: Any other risk group or factor, in addition to those present in work at height, specific to each environment or activity, which may directly or indirectly affect safety and health at work.

Rope access system: A work system in which ropes are used as a means of access and protection against falls.

Work positioning system: A work system that is designed to allow the worker to remain positioned in the work area, wholly or partially suspended, without the use of hands.

Fall Protection System (FPS): A system designed to eliminate the risk of a worker falling or to minimize the consequences of a fall.

Work restraint system: A fall protection system that limits movement so that the worker is not exposed to the risk of falling.

Fall arrest system: A fall protection system that does not prevent a fall, but stops a fall once it has started, thereby reducing its consequences.

Work at height supervision: The act of providing guidance – in person, semi-present or remotely – for the safe performance of work at a height.

Temporary anchor systems: those that are used for a specified period of time and removed when the services are completed, such as systems that are set up to perform a specific task or work on a work face.

Inert suspension: A situation in which a worker remains suspended from the safety system until help arrives.

Lanyard: connecting device of a safety system, adjustable or not, to support, position and/or limit the movement of the worker.

Estimated time to rescue: Estimated time between an undesirable occurrence during work at height, such as the worker falling or being suspended, and the worker being removed or stabilized in a condition that cannot cause harm to their health, such as that resulting from inert suspension.

Qualified worker: worker certifying the completion of specific course for the activity in an institution recognized by the official education system.

Fall arrest: safety device to protect the worker against falls during operations with vertical or horizontal movement, when connected with safety harness for fall protection.

Fall clearance zone: Area between the anchorage point and the nearest lower obstacle against which the worker could collide in the event of a fall, such as ground level or the floor below.

Annex I – Rope Access

Annex II – Anchor System