Safety review

Another method that is commonly used to identify safety problems in laboratory and process areas and to develop solutions is the safety review. There are two types of safety reviews the informal and the formal. 

The informal safety review is used for small changes to existing processes and for small bench-scale or laboratory processes. The informal safety review procedure usually involves just two or three people. It includes the individual responsible for the process and one or two others not directly associated with the process but experienced with proper safety procedures. The idea is to provide a lively dialogue where ideas can be exchanged and safety improvements can be developed. 

The reviewers simply meet in an informal fashion to examine the process equipment and operating procedures and to offer suggestions on how the safety of the process might be improved. Significant improvements should be summarized in a memo for others to reference in the future. The improvements must be implemented before the process is operated. 

Phosgene is a colorless vapor with a boiling point of 46.8°F. Thus it is normally stored as a liquid in a container under pressure above its normal boiling point temperature. The TLV for phosgene is 0.1 ppm, and its odor threshold is 0.5-1 ppm, well above the TLV. 

Aniline is a liquid with a boiling point of 364°F. Its TLV is 2 ppm. It is absorbed through the skin. 

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Methods for performing hazard analysis and risk assessment include safety review, checkhsts, Dow Fire and Explosion Index, what-if analysis, hazard and operabihty analysis (HAZOP), failure modes and effects analysis (FMEA), fault tree analysis, and event tree analysis. Other methods are also available, but those given are used most often. 

Safety Review. The safety review was perhaps the very first hazard analysis procedure developed. The procedure begins by the preparation of a detailed safety review report. The purpose of this report is to provide the relevant safety information regarding the process or operation. This report is generally prepared by the process engineer. A typical outline for this report follows. 

The safety review report is distributed to the committee which meets to work its way through the report, section by section, discussing safety concerns and potential improvements to the process or procedure. An individual must be designated to take minutes at the meeting and record suggested modifications. If the review concerns an existing process, the committee should perform a site visit to examine the actual equipment. 

The safety review technique is also usehil for small laboratory operations and small changes in existing processes. In these cases, the committee often consists of two or three people and any changes are often less formally recommended. 

Audits by INPO and the U.S. NRC aie a culmination of a high degree of self-auditing by the plant operators and the utihties themselves, often assisted by special third-party safety review boards set up to help carry out safety assessments (21). Self-auditing and self-criticism are essential to the process. These reflect the fundamental reactor safety principle that the owner-operator of the plant has the ultimate responsibiUty for plant safety. 

Pilot plants are often more hazardous than process plants, even though they are smaller ia size, for many reasons. These iaclude a tendency to relax standard safety review procedures based on the small scale, exceptionally qualified personnel iavolved, and the experimental nature of the research operations the lack of estabhshed operational practice and experience lack of information regarding new materials or processes and lack of effective automatic iatedocks due to the frequendy changing nature of pilot-plant operations, the desire for wide latitude in operating conditions, and the lack of hill-time maintenance personnel. 

To distinguish between a review and an audit, some definitions will be provided. A review is a critical examination or evaluation of any operation, procedure, condition, event, or equipment item. Reviews can take many forms and be identified as project reviews, design reviews, safety reviews, pre-start-up reviews, and so on. The following discussion of the review process will deal with project reviews associated with capital projects and focus on the area of process safety. 

The project review process involves multiple steps that should be definea in management gmdelines (CCPS, 1993, pp. 57-61). The steps include (1) review pohcy, (2) review scheduling, (3) reviewtech-nique, (4) review team representation, (5) review documentation, (6) review follow-up, (7) review follow-up verification, and (8) review procedures change management. These steps define how a review, whether it be a safety review, environmental review, pre-start-up review, or whatever, is conducted and how closure of review aclion items is achieved. 

Review Policy The review policy should estabhsh when project safety reviews should be done. All capital projects, large or small, should have one or more safety reviews during the course of the project. The number and types of review shoiild be stated in a management policy. Any reasons for exceptions to the policy should oe documented as well. The policy should address not only projects internal to a company, but also any joint ventures or turnkey projects by outside firms. 

Low temperatures can cause a phase separation in stabilized solutions in which case one phase can become deficient in stabilizer and subject to runaway reactions. Acrylic acid can crystallize out of stabilized solution, and subsequent thawing of these essentially pure acrylic acid crystals can initiate runaway reactions, often with severe consequences. Thawing of crystallized (frozen) materials needs to be accomplished using established procedures in thaw boxes or similar devices. If established procedures are not available, a safety review needs to be conducted and a procedure developed prior to thawing the material. 

How do you resolve pre-startup safety review issues and action items ... 

Once the PSSR team is satisfied with their review, a form such as Example 4-1, Pre-startup Safety Review Completion Form can be used to capture their approval for startup. For simple changes, this one-page form may be all that is required. In the case of extensive modifications, a detailed checklist of items examined by the team may accompany this form. It could include unsatisfactory findings as well as respective recommendations. If recommendations were made, these must be prioritized. Some may need to be resolved before startup others may be appropriately addressed after processing has begun. Some items reviewed by one company for extensive modifications and logged in addition to the one-page form are ... 

Example 4-1. Pre-startup safety review completion form... 

TOLLER CD. iHOiirraiuiiuK Pre-Startup Safety Review Form Form No. PSMADM09.501 Rev. 2 ... 

Did the Process Safety Information Change O YES O NO ( items indicates PSI) (If YES, initiate PSM-ADM-08, Pre-Startup Safety Review)... 

Are there other environmental or health and safety reviews or approvals (for example, need for public hearings, notification, registrations) which need to be obtained If yes, how long will it take to secure these approvals If yes, explain. 

Noronha, J. A., Seyler, R. J., and Torres, A. J., Simplified Chemieal Equipment Sereening for Emergeney Venting Safety Reviews Based on the DIERS Teehnology, Proeeedings of the Int. Symp. on Runaway Reaetions, pp. 660-680, Cambridge, MA, Mareh 7-9, 1989. 

In one site, the project team installing a DCS (Distributed Control System) carefully developed and tested techniques to make the displays clear for red-green color blind personnel (see discussion in 6.4). The displays were effective and were applauded by the operators. However, in subsequent DCS installation projects at the same site, different project teams made no provision to make displays visible to red-green color blind personnel. This inherently less safe condition was found during a design review at one unit and at the pre-start-up safety review for another unit. 

Inherent Safety Review Methods and Avaitahte Training... 

A number of companies have recently described their inherent safety review practices ... 

Exxon Chemical (French et al., 1996 Wixom, 1995) has developed an inherent safety review process, and its application at various points in the process life cycle. 

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