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In easily, out safely: confined space best practices

Thursday 19, Dec 2019

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3M Safety & Graphics


In easily, out safely: confined space best practicesConfined spaces can be complicated, and anyone, in any industry, can be exposed to working in and around them. ASH MAYOR outlines some best practices that will help you ensure those working in confined spaces are kept safe.

Confined spaces present some of the most challenging environments for health and safety professionals. From potentially toxic atmospheres to physically arduous conditions (such as extreme temperatures, hazardous materials, or the potential for falls), confined spaces often present unseen challenges. Confined spaces are areas that have been deemed to have met certain criteria: it is an enclosed or partially enclosed space which is not primarily designed to be occupied, is at normal atmospheric pressure while people are in it and is, or is likely to be, a risk to health and safety due to an unsafe level of oxygen, or contains contaminants including gases, vapours or dusts which may cause fire or explosion, or a harmful concentration of airborne contaminants, or engulfment. While complicated, there are some best practices that will help you ensure that workers in confined spaces are kept safe.

Training, assessment and testing

It is essential that workers have adequate training to function safely in the confined space. Training must be appropriate to the individuals’ roles and responsibilities. Workers must follow the established safe system of work that has been provided and training should include understanding the confined space permit system, isolation procedures, gas testing atmospheres, hazard identification, respiratory protection, rescue procedures and other specialised training for any particular tasks that will be performed. Prior to entry, the confined space should be ventilated, and the atmosphere must be tested to establish the oxygen concentration and determine the possible presence and levels of hazardous fumes, gases and vapours. As many of the hazards within confined spaces are not detectable by our senses, training in the correct procedures is vitally important to keep workers safe.

PPE, equipment and monitoring

Through the hazard identification and risk assessment process and working through the hierarchy of controls, you should identify any remaining hazards that will require personal protective equipment (PPE) in order to control the hazard. Various types of confined spaces will all have different access points, be it side entry, descending from above or crawling up through an entry point which will require different types of equipment in order to access the space safely. Ensure that the appropriate equipment is identified and sourced prior to the work being started. When working in a confined space, communication and monitoring should also be a constant.

The communication system must be established prior to entry and all workers must fully understand the system — any specific hand signals or tugs on a rope for instance. The stand-by person must also have a system that will allow them to raise the alarm in the event of an emergency. There may be a need to limit the time workers can spend in a confined space. This could be due to extreme conditions of temperature and humidity, exposure limits for hazards within the space or limitations of respiratory equipment being used. The stand-by person will be responsible for monitoring these conditions and ensuring the welfare of the workers within the space.


Most fatalities involving confined space work occur when would-be rescuers enter a space and become casualties themselves. It is therefore essential that potential rescuers have thorough training and have rehearsed and proven that the measures put in place to affect rescue are suitable. Any work involving confined space entry needs to have a rescue plan and the needs of a rescue team and what training is required for them to perform a rescue operation must be evaluated, including equipment that may be needed to help someone out of a dire situation.

Ash Mayor, training specialist at 3M, Safe-T-Bulletin

Ash Mayor is a Training Specialist at 3M.

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