Tolerability of Risk

A risk management framework (abbreviated to TOR) which assesses the risks of a hazardous activity and the toleration of risk and concerns involved with the activity which an individual or organisation is willing to accept. Implementing the concept of TOR promotes a positive safety culture in the workplace, leading to reduced accidents and incidents and contributes to a more productive and enjoyable working environment.

The risk involved can be allocated to one of three regions: broadly acceptable region; tolerable region; and unacceptable region. Any activity that is categorised as being within the unacceptable region should not be undertaken because the risk cannot be justified (there could in theory be exceptional circumstances where it may need to go ahead, but in normal practice this wouldn’t happen) unless it can be adapted to reduce the risk to that of a tolerable risk. The boundaries for the regions might be defined using the HSE 2001 publication ‘Reducing risks, protecting people. HSE’s decision-making process’ (https://www.hse.gov.uk/enforce/assets/docs/r2p2.pdf), although for more routine business activities they suggest their guidance on ‘Managing risks and risk assessment at work’(https://www.hse.gov.uk/simple-health-safety/risk/index.htm).

The HSE have an inverted triangle which illustrates the concept of TOR, with an adapted version being shown below.


A comprehensive risk assessment is initially needed to identify current and potential hazards in the workplace. The establishment of tolerability criteria can then take place to determine the acceptable level of risk involved with activities, and this will be heavily influenced by industry best working practice and regulatory requirements.

The aim might be to have activities with risks that lie within the broadly acceptable region, in which case they will typically be classed as low risk and more easily controlled.

The tolerable region is that where the focus of risk assessments and controls will reside for grounds maintenance activities and any remaining, or residual, risks must be as low as reasonably practicable (ALARP). Being within the tolerable region does not mean that the risk is acceptable as such, but rather that the benefits from carry out the activity along with the necessary and correctly installed controls means the individual or organisation are willing to bear the risk, i.e. tolerate it.

Creating appropriate employee training programmes, as well as written guidance, and ensuring the effective implementation and monitoring of identified control measures will help to keep the tolerability of risk to within the defined region, always aiming to reduce risks further through routine review.