Safe operations

The health, safety and well-being of our employees is our top priority. We understand that our operational environment may be hazardous, and for this reason, the identification and management of material risks are crucial in our business approach. We consistently strive to create a zero harm working environment, regardless where our people work or what type of work they are engaged in.

We are committed to zero harm and have put in place rigorous processes to ensure that every employee and contractor fishes his or her work day as safely and as healthy as they were when they reported for work. Every day we strive to eliminate fatalities while reducing the number and severity of injuries.

Health study

An epidemiological study on the potential effects of low level occupational radiation exposures on mine workers started in 2015 in cooperation with the Centre for Occupational and Environmental Health at the University of Manchester in the United Kingdom. An external advisory committee, consisting of community leaders and Government representatives, is assigned to provide external input and advice.

The study is expected to be finalised during the first half of 2019. For more information, visit the Rössing website, Reports and Research section.

Occupational health management

We firmly believe that occupational disease and illness can be prevented, provided that risks are properly identified, managed and controlled.

Our occupational health, hygiene and wellness programmes are aimed at preventing ill health, but also promoting good health and well-being.

We identify and quantify health hazards to enable us to minimise exposure and prevent injury and illness that may otherwise develop. In adherence to legislative requirements as well as to the risk-based occupational health standards of Rio Tinto, some of our key programmes include, but are not limited to:

  • noise exposure control;
  • workplace ergonomics management;
  • health and medical monitoring;
  • hazardous substances exposure control; and
  • fitness for work and fatigue management.

Rössing’s Critical Risk Management programme seeks to identify and assess hazards arising from our activities and manage associated critical risks to the lowest practical level .

 

Radiation safety

Exposure to ionising radiation at Rössing Uranium was controlled through a comprehensive programme that is described in our radiation management plan (RMP). The RMP is updated regularly and can be accessed via our website with the ‘Reports and Research’ tab. The RMP implementation reports for the past few years are also available for download on our website.

Personal monitoring
Our occupational radiation protection programme includes a comprehensive monitoring programme for measuring the occupational exposure to ionising radiation of all employees (personal monitoring).

Three major exposure types are covered by part of this routine monitoring programme:

  • Internal exposure to alpha radiation from the inhalation of radon and the short-lived decay products of radon;
  • Internal exposure to alpha radiation from the inhalation of the long-lived dust; and
  • External exposure to gamma radiation.

For each of these three pathways, an annual dose is obtained.

The workforce at Rössing Uranium is categorised into 19 similar exposure groups (SEGs), according to the potential radiation exposure encountered during different work processes. The annual doses from the three pathways mentioned are then added up to find the total annual radiation exposure dose for the individual SEG.

In 2018, we collected about 1,000 personal radiation exposure samples compared to about 600 samples in 2017.

Over the years, we have gathered a comprehensive database of radiation exposure measurements by pathway and by SEG. The regulatory dose limit is 20 millisievert (mSv) per year.

The annual dose in 2018, when averaging over the entire workforce was 1.2 mSv, which is about 0.2 mSv higher than reported for 2017. Assuming a working year of 2,000 hours, the extrapolated averaged dose by SEG is displayed shown in Figure 10. The dashed line is the average of 1.2 mSv per year, the solid circles represent the 2017 results.

Although the annual dose is slightly higher than in previous years, this weighted average dose is extremely low, as it includes background radiation for the duration of the work year.

Area monitoring
In addition to personal monitoring, the area monitoring is a key element in our radiation protection programme. In the Final Product Recovery (FPR) area, the surface contamination is regularly monitored using wipe tests with subsequent analysis of the activity of the collected material.

In 2018, our internal target of 1 becquerel (Bq/cm2) surface contamination was exceeded constantly (the target was reached in 2017). To reduce the surface contamination, it was decided to stop drumming for a short time in order to do a proper clean-up and maintain the plant before restart. As a result, the surface contamination dropped to about 0.6 Bq/cm2, which is well below target.

A programme to monitor radon gas and radon progeny was started. Measurements indoors (in offices) revealed the effect of air circulation on the concentration of the radioactive elements. Outdoor monitoring results will be implemented in a geographic information system (GIS) map.

The goal is to visualise radiation levels of long-lived radioactive dust, radon and gamma radiation across the whole mine using maps and 3D scenes. So far, we monitored one outdoor area for radon and radon progeny for one month, and a first map only including LLRD and gamma radiation was created.

Sealed sources
Sealed sources are used in different process applications such as uranium-level monitoring in the drum filling process. Sealed sources contain highly radioactive substances and are manufactured in such a manner that in normal use, radioactive material cannot be dispersed.

However, worldwide numerous accidents are reported where persons handling the source were not aware of the risk, which illustrates the potential danger from sealed radioactive sources.

In 2018, we removed the last five sealed sources from process applications at the Final Product Recovery plant and the Primary Crusher, and stored them safely in our Radiation Storage Facility. The next step is to explore the possibility of removing the now 14 stored sealed sources from the mine site. In this regard, discussions around the various possible removal or storage options with the National Radiation Protection Authority (NRPA) have already started.

To avoid the spread of contamination, all material leaving the mine site has to be radiation cleared, which means the level of contamination must not exceed 0.4 Bq/cm2. By monitoring all the equipment leaving the mine site, we ensured that the level of 0.4 Bq/cm2 was not exceeded. In case the surface contamination of the equipment exceeded 0.4 Bq/cm2, it was rejected for removal and sent for cleaning.

Besides the clearance of individual items, ranging from tools to forklifts, a total of almost 1,200 tonnes of scrap metal and about 35 tonnes of conveyer belts were removed from the mine site after being cleared of radiation contamination.

Uranium spillage drill
A uranium spillage drill took place in 2018, in which four uranium mines participated, namely Rössing Uranium, Swakopmund Uranium, Orano and Bannerman. In the drill, which simulated a uranium spillage during road transport, the participants could validate their ability to react to emergencies, while also learning from the procedures of the different mines.

Training programme
To improve awareness to the risk of radioactivity, internal training is one of the key elements in our radiation safety programme. Both new and existing employees need to be informed about the risk of radiation and hence know how to minimise radiation exposure.

All new employees have to pass a radiation safety induction, which is followed by a bi-annual radiation safety refresher. In 2018, 204 individuals, including regular employees, contractors and apprentices, attended the radiation safety induction, while 228 workers attended the radiation safety refresher training.

From July 2018 onwards, we made the radiation safety refresher training programme accessible online, as the online option is increasingly frequently chosen.


Figure 10: Personal radiation exposure dose by similar exposure group (SEG),
2018 Regulatory annual dose limit: 20 mSV (Annual dose in milli-sievert)