ProSafe conducts a Hazard Identification in order to establish the safety circuit performance criteria when reviewing the electrical documentation only.
The Hazard I.D. only identifies the ‘task’ for the operator based on the design and layout for the installation or apparatus as it is intended to be used. It does not identify any misuse or deliberate actions that are not part of the operator’s tasks. (Such as climbing over or through guard openings and/or tooling or part height barriers intended for use as barricades into hazardous areas). For reasonably foreseeable misuse hazards are identified for inadvertent access based on non-operator tasks such as maintenance and setup.
Following the requirements of the ANSI R15.06 for risk assessment method, tasks and hazards are identified and risk estimation is applied on the basis of severity of the injury, exposure to the hazard, and ability to avoid the hazard. Using the hazard severity, exposure, avoidance criteria, a risk reduction category is determined through a risk reduction decision matrix prior to safeguard selection. Another acceptable method is the ISO 13849 Standard.
A standard set of task descriptions are used so that only hazards associated with a particular task are assessed. Focusing on the task and the hazards provides the designer with the level of safeguards required for the particular task.
Review of the Operator’s Envelope and the results of our assumptions appear in the Load/Unload and Cycle Start sections of the assessment form. The Machine Function Envelope results appear in the Operating Cycle, Fixing Part Jams and Observations sections. Teaching/Setup and Maintenance functions typically are not part of the normal production operation of the machinery and follow a specific procedure; therefore, they are reviewed separately from the operator and machine envelopes described above.
The risk reduction decision is assigned a category number ranging from 1 to 4, which then provides the minimum required safeguard performance and circuit performance.
In addition, the Hazard identification uses Performance Level required categories (PLr) from EN ISO 13849-1. Probability of dangerous failure per hour is determined based on the PLr (a, b, c, d, and e). PLr looks at the component that could fail, causing a hazardous condition to exist.
The risk assessment for each hazard identified involves estimating the capability of the device or process to cause injury or property damage. By combining the severity, frequency and probability of each hazard a degree of risk can be determined for selecting the appropriate level of guarding.
When all of the hazards have been identified and their corresponding risks for injury or property damage are determined, the next step is to implement the appropriate safeguarding. The hazards could be dealt with using individual safeguards or using a single broad safeguard. Which is the appropriate method? There isn't a standardized solution for the safeguarding of every system and for this reason the safeguards are designed based upon each individual situation.
An overall assessment of the system is conducted in order to examine the safeguarding options and select a method that will provide effective protection without being a detriment to machine operation or installation cost. The recommendations produced by the overall assessment provide a designer with the opportunity to specify the safeguards that are appropriate for your operating environment.
Based on the Ontario Ministry of Labour Regulation 851 (Canada)
The evaluation involves an assessment of compliance with the Ontario Ministry of Labour Regulation 851. This assessment is a requirement for all industrial equipment or processes but not necessarily for a Section 7 Pre-Start Health and Safety Review. The Ministry of Labour Regulation 851 assessment is involved in order to assure that all safety aspects are thoroughly investigated.
What must the Pre-Start Health and Safety Review report include?
When a Pre-Start Health and Safety Review is carried out, a written report is required that must contain the following:
While professional engineers who undertake PSHSRs are responsible for identifying and addressing issues of compliance with the applicable sections of Regulation 851, professional engineers do not bear responsibility for implementing the report recommendations. The employer remains responsible for ensuring that all requirements of the Occupational Health and Safety Act and Regulations are complied with in the workplace. Even where a Pre-Start Health and Safety Review is not required or an exemption from the requirements of Section 7 applies, the employer must ensure that workers are protected before operating any apparatus, structure, protective element or process in the workplace.