NR33 – Working in Confined Spaces

(Last amendment on August 29, 2012)

33.1 Objective and Definition

33.1.1 This standard aims to establish minimum requirements for identification of confined spaces also recognition, assessment, monitoring and control of existing risks so as to permanently ensure the safety and health of the workers who interact directly or indirectly in these spaces.

33.1.2 Confined space is any area or environment not designed for continuous human occupation, which has limited access and egress, whose existing ventilation is insufficient to remove the contaminants or where there might be oxygen deficiency or enrichment.

33.2 Responsibilities

33.2.1 It is up to the employers to:

a) formally indicate a technically responsible person for compliance with this standard;
b) identify confined spaces existing in the establishment;
c) identify specific risks for each confined space;
d) implement a system of health and safety management for confined spaces, by technical preventive, administrative, personal measures, as well as emergency and rescue measures,so as to permanently ensure environments with adequate working conditions;
e) ensure continuous trainings for workers on risks, control measures, emergency and rescue in confined spaces;
f) ensure that access to confined spaces occurs only after issuing a written Entry and Work Permit in accordance with the form in Annex 2;
g) provide the contractors with information about risks in the areas where they will conduct their activities and training is required for their employees;
h) monitor the implementation of health and safety measures of the contracted companies providing means and conditions so they can act in accordance with NR33;
i) stop all and any type of work in case of suspicion of serious and imminent risk condition, abandoning the work site immediately; and
j) ensure up to date information regarding the risks and control measures prior to each access to confined spaces.

33.2.2 It is up to the employees to:

a) collaborate with the company in complying with this NR;
b) use the tools and equipment provided by the company properly;c) notify the Entry Supervisor or Watchmen of any conditions that pose risk against health and safety of their own or others, as known by them;
d) comply with the procedures and instructions received in trainings with respect to confined spaces.

33.3 Health and safety management in confined spaces

33.3.1 Health and safety management shall be planned, programmed, implemented and evaluated, including technical preventive measures, administrative measures and personal measures and training regarding to work in confined spaces.

33.3.2 Technical preventive measures:

a) identify, isolate and tag the confined spaces to prevent unauthorized entry;
b) anticipate and recognize the risks inside the confined spaces;
c) carry out an assessment and control physical, chemical, biological, ergonomic and mechanical risks;
d) predict the implementation of latches, locks, relieves, sealing and labeling;
e) implement necessary measures to eliminate or control atmospheric hazards in confined spaces;
f) evaluate the atmosphere in confined spaces before the entry to verify that it is safe inside;
g) maintain acceptable atmospheric conditions at the entrance and throughout the execution of the work, monitoring, purging, washing, inertizing confined spaces;
h) continuously monitor the atmosphere in confined spaces in areas where authorized workers carry out their tasks, to verify that the conditions for access and occupancy are safe;
i) ventilation with pure oxygen is prohibited;
j) test measuring devices before each use; and
k) use direct reading equipment, intrinsically safe, provided with alarm, calibrated and protected against electromagnetic emissions or radio frequency interference.

33.3.2.1 The fixed and portable equipments, including communication and vertical and horizontal movement devices, shall be appropriate to the risks of confined spaces;

33.3.2.2 The equipments in classified areas shall be certified or have document contemplated in the Brazilian System on Conformity Assessment – INMETRO.

33.3.2.3 Initial atmospheric assessments shall be conducted outside the confined space.

33.3.2.4 Take measures to eliminate or control the risk of fire or explosion in hot works, such as welding, heating, grinding, cutting or others who may release open flames, sparks or heat.

33.3.2.5 Take measures to eliminate or control the risk of flooding, burying, engulfment, fire, electric shock, static electricity, burns, falls, landslides, impacts, crushs, amputations and others that may affect the health and safety of workers.

33.3.3 Administrative measures:

a) keep updated records of confined spaces, including deactivated confined spaces, and their risk;
b) define measures to isolate, tag, control or eliminate the risks in confined spaces;c) maintain permanent signs at the entrance of confined spaces according to Annex I;
d) implement procedures for working in confined spaces;
e) adapt Entry and Work Permit system provided in Annex II to the confined spaces;
f) fill, sign and date the Entry and Work Permit Form, in three copies, prior to entry of workers in confined spaces;
g) have a control system that allows traceability of Entry and Permit;
h) give one of the authorized workers and Watchman a copy of Entry and Work Permit;
i) terminate Entry and Work Permit when operations are completed, when an unforeseen condition occurred or when the work is interrupted;
j) keep the procedures and Entry and Work Permits for 5 years;
k) make the procedures and Entry and Work Permits available for authorized workers, their representatives and labor inspection;
l) designate the persons who will participate in entry operations, identifying the duties of each worker and providing the required training;
m) establish procedures to supervise the work outside and inside confined spaces;
n) ensure that access to confined spaces will only be started under monitoring and authorization of qualified supervision;
o) ensure that all workers are informed of existing risks and control measures in the workplace; and
p) implement a Respiratory Protection Program in accordance with risk analysis, considering the place, complexity and type of work to be performed.

33.3.3.1 Entry and Work Permit is only valid for each entry.

33.3.3.2 In establishments where there are confined spaces, as a complement to this NR, the following normative acts shall be observed: NBR 14606 – Service Posts – Confined Space Entry; and NBR 14787 – Confined space – accident prevention, procedures and protection measures, and their subsequent amendments.

33.3.3.3 Work procedures shall include at least: purpose, scope, technical basis, responsibilities, skills, preparation, issuance, use and cancellation of Entry and Work Permit, training for workers, risk analysis and control measures.

33.3.3.4 Procedure for working in confined spaces and the Entry and Work Permit shall be evaluated at least once a year and revised whenever there is a change in risks, with the participation of Specialized Services in Occupational Health and Safety (SESMT) and Internal Commission on Accident Prevention (CIPA).

33.3.3.5 Procedure for entry in confined spaces shall be reviewed upon the occurrence of any of the following circumstances:

a) unauthorized entry into a confined space;
b) identification of hazards not addressed by the Entry and Work Permit;
c) accident, incident or condition not foreseen during the entry;d) any change in the activity performed or in the configuration of confined space;
e) solicitation from SESMT or CIPA; and
f) identification of safer working conditions.

33.3.4 Personal Measures

33.3.4.1 Every worker assigned to work in confined spaces shall be subjected to medical examinations specific to the function that will be performed, as set forth in NR7 and NR31, including psychosocial risk factors with the issuance of Attestation of Occupational Health (ASO).

33.3.4.2 To train all employees involved, directly or indirectly with confined spaces, on their rights and duties, risks and control measures, as provided in item 33.3.5.

33.3.4.3 The number of workers involved in the work in confined spaces shall be determined according to risk analysis.

33.3.4.4 It is forbidden to perform any work in confined spaces individually or in isolation.

33.3.4.5 Entry Supervisor shall perform the following functions:

a) to issue the Entry and Work Permit prior to the beginning of activities;
b) to run the tests, check the equipments and the procedures contained in the Entry and Work Permit;
c) to ensure that emergency and rescue services are available and the means to trigger them are operative;
d) to cancel entry and work procedures when necessary; and
e) to close the Entry and Work Permit after the end of work.

33.3.4.6 Entry Supervisor can carry the function of Watchman.

33.3.4.7 The Watchman shall have the following functions:

a) continuously maintain accurate number of authorized workers in the confined space and ensure that everybody leaves at the end of the activity;
b) remain outside the confined space, near the entrance, in permanent contact with the authorized workers;
c) adopt emergency procedures, engaging the rescue workers, public or private, when necessary;
d) operate the movers of people; and
e) order the abandonment of the confined space whenever any sign of warning, danger, symptom, complaint, prohibited condition, accident, unforeseen situation is recognized or when the task cannot be effectively performed, or be replaced by another Watchman.

33.3.4.8 The Watchman shall not be able to perform any other tasks that may undermine the main duty which is to monitor and protect the authorized workers.

33.3.4.9 It is for the employer to provide and ensure that all workers who step into the confined spaces have all the equipment to control the risks, as provided in the Entry and Work Permit.

33.3.4.10 In the presence of atmosphere immediately dangerous to life or health (Atmosphere IDLH), the workers shall use self-contained breathing apparatus with positive pressure or compressed air line respirator with auxiliary escape cylinder.

33.3.5 Training for work in confined spaces

33.3.5.1 It is forbidden to assign any work in confined spaces without prior training the workers.

33.3.5.2 The employer shall develop and implement training programs whenever there is any of the following:

a) change in procedures, conditions or work operations;
b) any event indicating the need for further training; andc) when there is a reason to believe that there are deviations in the use or in the procedures for entry in confined spaces or that the knowledge is not adequate.

33.3.5.3 All authorized workers, Entry Supervisors and Watchmen shall receive periodic training every 12 months, with a minimum workload of 8 hours.

33.3.5.4 The initial training of authorized workers and Watchmen shall have minimum hours of sixteen hours, be held within the working hours, with following content:

a) definitions;
b) recognition, evaluation and control of risks;
c) operation of equipments;d) procedures and use of the Entry and Work Permit; and
e) notions of rescue and first aid.

33.3.5.5 The training of Entry Supervisors must be realized within the working hours, with content provided in sub-item 33.3.5.4, together with:

a) identification of confined spaces;
b) criteria of indication and use of equipments to control the risks;
c) knowledge on safe practices in confined spaces;
d) occupational health and safety legislation;
e) respiratory protection program;
f) hazardous areas; and
g) rescue operations.

33.3.5.6 All Entry Supervisors shall have minimum forty hours initial training.

33.3.5.7 Trainers designated by technical supervisor shall have proven proficiency on the subject.

33.3.5.8 A certificate shall be issued at the end of the training, containing employee’s name, training content, course load, specification of the type of work and confined space, date and location of the training, with signatures of instructors and technical supervisor.

33.3.5.8.1 A copy of the certificate shall be given to the employee and the other copy shall be kept in the company.

33.4 Emergency and Rescue

33.4.1 The employer shall establish and implement emergency and rescue procedures adequate to confined spaces, including at least:

a) description of possible accident scenarios, derived from the Risk Analysis;
b) description of the rescue and first aid measures to be performed in case of emergency;
c) selection and techniques for using equipments of communication, emergency lighting, search, rescue, first aid and transportation of victims;
d) engagement of responsible team, public or private, for the implementation of rescue and first aid measures for each service to be held; and
e) annual rescue drills on the possible accident scenarios in confined spaces.

33.4.2 The personnel responsible for implementation of rescue measures shall have physical and mental fitness compatible with the activity.

33.4.3 The training of rescue team shall cover all possible accident scenarios identified in the risk analysis.

33.5 General Provisions

33.5.1 The employer shall ensure that workers can stop their activities and leave the work site whenever they suspect that there is a serious and imminent threat to their health and safety or the third parties.

33.5.2 Contracting and contracted parties are jointly and severally responsible for complying with this NR.

33.5.3 It is forbidden to enter and perform any work in confined spaces without issuing a Entry and Work Permit.


Annex I – Signage
Annex II – Entry and Work Permit (PET)
Annex II – Glossary