Hi everyone! Today, we will finally start to look at laws regarding radiation. Before we begin, however, we would need to come up with our own definition of what a radioactive pollutant is, and then look at how Singapore’s Radiation Protection Act (“RPA”) defines it. Without further ado, let us begin!
Our Definition of Radioactive Pollutant
Based on what we have discussed previously, sources of radiation can be natural or anthropogenic, but both require a process which releases ionising electromagnetic waves (NEA, 2019). As the effects of radiation can only be dangerous to human health after a certain threshold, the amount of ionising radiation a material can produce is important as well. In addition, it should be recognised that these pollutants can either pollute by itself or contaminate different mediums. Thus, we define a radioactive pollutant as:
“A substance or medium that releases ionising radiation at doses harmful to human health”.
For the sake of comparison with the RPA, we have decided to exclude the effects of radiation pollution on the environment. We acknowledge the impacts that radiation pollution can cause to the environment in our previous post but also must consider the difficulty in quantifying these effects at present. The most equitable option, in the case of radiation pollution, is the ALARA principle – where ALARA stands for as low as reasonably achievable (CDC, 2015). This ensures that radiation pollution does no harm to human health, and consequently, the environment. With this, let us look at how Singapore’s RPA defines a radioactive pollutant!
Radiation Protection Act (“RPA”)
The RPA defines radioactive pollutants rather succinctly. We have summarised it as seen below to better help you, our readers, understand it!
“Radioactive Waste” means any waste which consists wholly or partly of –
- The substance or article which, if it were not waste, would be radioactive material; or
- A substance or an article which has been contaminated in the course of production, keeping or use of radioactive material or by contact with, or proximity to other waste falling within paragraph (1) (SSO, 2007)
Some definitions of the words used in the RPA is as follows:
“radioactive material” means any article containing radioactive substance giving it a specific or total radioactivity exceeding the prescribed level, and includes any article containing any nuclear material
“radioactive substance” means a radionuclide or mixture of radionuclides, either alone or in combination with other elements
“radionuclide” means an isotope of any element which spontaneously emits any ionising radiation (SSO, 2007)
While the various keywords may seem confusing, it is actually rather simple when broken into parts. “Radionuclide” is understood as the basic source of ionising radiation, and a mixture or pure amount of “radionuclide” is a “radioactive substance”. Next, any object that contains a “radioactive substance” that is above a radioactive threshold is a “radioactive material”. Finally, waste that is at least in part made of “radioactive material” itself or objects that interact with a “radioactive material” is considered a “radioactive waste”
After arranging the RPA definitions as such, it makes the definition much simpler and easier to understand as the definitions are otherwise straightforward. With this, we have come to the end of today’s post. In our next and final post on radioactive pollutants, we shall discuss similarities and differences between the two definitions of radioactive pollutants as well as our opinions on the RPA’s definitions!
Lee Yang
References
CDC. (2015). ALARA – As Low As Reasonably Achievable.
NEA. (2019). Ionising Radiation. Retrieved from https://www.nea.gov.sg/our-services/radiation-safety/regulatory/ionising-radiation
SSO. (2007). Radiation Protection Act. Retrieved from https://sso.agc.gov.sg/Act/RPA2007.