Thursday, May 27, 2021
ONRSR is reminding rail transport operators about a range of risks, causes and controls associated with A1 SPADs
A Signal Passed at Danger (SPAD) is where rolling stock passes a stop indication / aspect or exceeds the limits of authorised movement without authority. As per ONRSR’s Reporting Requirements for Notifiable Occurrences, an ‘A1 SPAD’ is “When a SPAD has occurred and, according to available evidence, a stop aspect, indication or end of movement authority was displayed or given correctly and in sufficient time for the train to be stopped safely at it.”
Such incidents can result in injuries or fatalities, especially where the A1 SPAD leads to a derailment or collision with another train (see the Safety Message: Train to train collision). While ONRSR’s investigations into A1 SPADs have identified several causes and contributing factors, there are also several mitigations that can minimise the risks. While not exhaustive, given the range of operational environments within the Australian rail industry, the following causes/contributing factors and controls should be noted.
While not an exhaustive list, ONRSR is aware of the following controls that are available and have been used in railways both in Australia and overseas. rail transport operators (RTO) should note that there are safety and operational benefits and detriments associated with each control. Operators must consider a range of factors, including the likelihood of the hazard and the degree of harm to determine what controls are reasonably practicable to implement – see the ONRSR Guideline – Meaning of duty to ensure safety so far as is reasonably practicable SFAIRP for more information.
The main types of engineering controls include signalling and train protection systems such as:
Organisational controls include:
Lineside/wayside signal controls include:
Rolling stock controls minimise distraction and help position the driver to sight signals through: