Process Hazard Analysis Revalidations

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Process Hazard Analysis RevalidationsRequirements & Purpose

What are the requirements?• Revalidate and update the Process Hazard

Analysis at least every five years after its initial or previous completion.

• Revalidation to be performed by a qualified team.

What’s the purpose?• Comply with the OSHA PSM [29 CFR

1910.119(e)(6)] and EPA RMP [40 CFR 68.67(f)] regulations.

• Ensure that the PHA is consistent with the current process.

Process Hazard Analysis RevalidationsPhilosophy – To Re-do or Read Through?

How should I decide?• Thoroughness of the initial or

previous PHA• Did we re-do or read through

five years ago?• Who was present in the

previous PHA?• Changes to the process in the

last five years – significant or minor?

Process Hazard Analysis RevalidationsPhilosophy – To Re-do or Read Through?

• OSHA Letter of Interpretation (June 28, 2998):• “Employers must establish the scope and extent of their PHA

updates and revalidations to include at least the following: evaluations of existing PHAs for accuracy and completeness using the criteria set forth in 1910.119(e)(3);

• checks to ensure that modifications to processes since the last PHAs have gone through management of change procedures or PHAs when required and that those changes are reflected in the PHAs;

• an evaluation of process safety information (PSI) to ensure that it is complete, current and accurate;

• verifications to ensure PHA specified procedures are adequate, up-to-date and are being implemented;

• determinations that existing PHA recommendations have been documented in their required respective areas such as PSI, PHAs, and procedures (operating, mechanical integrity, emergency response, etc.) and have been implemented;

• a review of all incident investigation reports required by 1910.119(m) to assure all affected PSI, procedures, training, etc., have been updated to reflect recommendations set forth in the subject reports and that appropriate information from those reports have been incorporated into the PHAs.

• Finally, OSHA intends that the PHA update and revalidation be documented.”

Process Hazard Analysis RevalidationsPreparing for the PHA - Summary

• Review implementation status of previous PHA recommendations.

• Verify accuracy of PSI:– Piping diagrams– Normal operating conditions– Safety systems

• List any changes to the process in the last five years (i.e., MOC review).

• Review five year accident history / incident investigation records.

• Ensure SOPs are current.

Process Hazard Analysis RevalidationsPreparing for the PHA –

RAGAGEP

• Define recognized and generally accepted good engineering practices (RAGAGEPs) used to design, operate, and maintain your process.• Mechanical, Fire, and Building Codes• Standards – ANSI/ASHRAE 15, ANSI/IIAR 2• Guidelines – IIAR Bulletins• Manufacturer’s Recommendations

Process Hazard Analysis RevalidationsPreparing for the PHA –

RAGAGEP• IIAR Bulletin 109 – Safety System Inspections• IIAR Bulletin 110 – Maintenance Schedules• IIAR Bulletin 111 – Ventilation Design and

Maintenance• IIAR Bulletin 114 – Labeling• ANSI / ASHRAE Standard 15 – Ammonia Relief

Discharge Locations• ANSI/IIAR 2 – Ammonia Sensor Settings and Actions• ANSI/IIAR 2 – E Stop Locations• EPA Ammonia Refrigeration System Alert Bulletin

• The PHA methodology must be “appropriate to determine and evaluate the hazards of the process being analyzed.” [40 CFR 68.67(b) & 29 CFR 1910.119(e)(2)]• What If Analysis

• Develop “what if” questions around equipment failures, process upsets, and human factor issues.

• Hazard and Operability Study (HAZOP)• Use of Guidewords to identify deviations from the design intention.

• Checklists

Process Hazard Analysis RevalidationsPreparing for the PHA –

Selecting the PHA Methodology

Process Hazard Analysis RevalidationsPreparing for the PHA –

Who’s on your team?• “The PHA shall be performed by a team with expertise in

engineering and process operations, with at least one employee who has experience and knowledge specific to the process being analyzed. Also, one member of the team must be knowledgeable in the specific PHA methodology being used.” [40 CFR 68.67(d) & 29 CFR 1910.119(e)(4)]• Design Engineers• Operations and Maintenance Personnel• Refrigeration Contractor• Safety / Environmental Management• PHA Leader & Recorder• Regulatory Representative

Process Hazard Analysis RevalidationsPerforming the PHA

• Identify hazards associated with the process using selected methodology.

• Determine causes and consequences of each potential hazard.

• Discuss any incidents that have occurred at your facility in relation to each potential hazard.

• Identify the administrative and engineering safeguards associated with each potential hazard.

• Determine risk ranking for each hazard discussed.

• Postulate mitigation measures to reduce the consequences and/or likelihood of each potential hazard.

Process Hazard Analysis RevalidationsPerforming the PHA

HAZOP Guide Words

• No Flow• Reverse Flow• More Flow• Less Flow• More Level• Less Level• More Pressure• Less Pressure• More Temperature• Less Temperature• More Viscosity• Less Viscosity• Agitation

• Composition Change• Contamination• Relief• Instrumentation• Sampling• Corrosion/Erosion/Materials

of Construction• Service Failure• Abnormal Operation• Maintenance• Ignition• Spare Equipment• Safety

Process Hazard Analysis RevalidationsPerforming the PHA

Risk RankingQualitative Definitions of Probability of Occurrence of an Accident

(Frequency Ranking)

A Frequent0 to 1 years More than once per year

B Periodical Every 1 to 10 yearsAt Least once each decade

C Occasional Every 10 to 100 yearsProbably during the life of the plant

D Possible Every 100 to 10,000 yearsNot expected at this plant, but could occur

E Improbable Not for 10,000 or more yearsNot expected or likely to occur at all

Process Hazard Analysis RevalidationsPerforming the PHA

Risk RankingQualitative Definitions of Severity of Consequences to

People During an Accident (Criticality Ranking)

I Catastrophic Results in death

(or damage and production losses > $1,000,000)

II Severe Results in multiple injuries

(or losses between $100,000 and $1,000,000)

III Moderate Results in a single injury

(or losses between $10,000 and $100,000)

IV Slight Results in operational problems only

(or losses <$10,000)

Process Hazard Analysis RevalidationsPerforming the PHA

ConsequencesFrequency

A: Frequent

B: Periodical

C: Occasional

D: Possible

E: Improbable

I: Catastrophic 1 1 2 4 4

II: Severe 1 2 3 4 4

III: Moderate 2 3 4 4 4

IV: Slight 4 4 4 4 4

RISK MATRIX

RISK CODE1 - Critical2 - Undesirable3 - Acceptable with controls4 - Acceptable

RISK MATRIXRisk Code:

1: Critical Must be improvedMitigate within six months with administrative or

engineering controls(to reduce the risk code to 3 or more)

2: Undesirable Should be improvedMitigate within one year with administrative or

engineering controls (to reduce the risk code to 3 or more)

3: Acceptable With ControlsVerify need for engineering controls, or that

administrative controls are in place for hazard

4: Acceptable No mitigating action required for identified hazard

Process Hazard Analysis RevalidationsPerforming the PHA

Process Hazard Analysis RevalidationsPerforming the PHA

Deviation Causes Consequences C Safeguards F R Recommendations / Comments

Design Notes

No Flow

Less Flow

More Flow

Reverse Flow

More Level

Less Level

More Pressure

Less Pressure

More TemperatureLess Temperature

Viscosity

Agitation

Project Title: Project No: Date: P&ID Title: Drawing No: HAZOP Session:

Drawing Revision No: HAZOP Leader:Process Description: Node A:

Process Hazard Analysis RevalidationsPerforming the PHA

P

PP

S

HTS

HSS

HPL

HTS

HTR

L

HTR

S

HTRL

HTRS

H IG H TEM PER ATU E

RECIRCULATOR

3 HP3 HP

PRV

FR O M D O C K E V A P S

TO D IF F U S IO N T A N K

TO HIG H T E M P C O M P R E S S O R S

FR O M HIG H P R E S S U R E R E C E IV E R

TO C O O LER E V A P O R A T O R S

FR O M C O O LE R E V A P O R A T O R S

Process Hazard Analysis RevalidationsPerforming the PHA

• Ensure the previous PHA adequately satisfied the requirements of a PHA:

• Previous incidents• Safeguards and the consequences of the safeguard

failing.• Engineering and administrative control relationships.• Facility Siting

• Engine Room exhaust vs. Ventilation Intake• Roof Hazards• Access to Eyewash / Safety Showers

• Human Factors• Qualitative Assessment of Frequency and

Consequences

Process Hazard Analysis RevalidationsRecommendation Tracking

• Develop a written schedule for completing action items.

• Assign responsibilities.• Meet periodically to review status of

recommendations and ensure progress is being made.

• Document recommendation review meetings and actions taken to implement recommendations.

• Maintain evidence that shows progress or completion of action items.

• Review status/outcomes with operating, maintenance, and any other persons who are affected by the recommendations.

Process Hazard Analysis RevalidationsDocumentation

• All Process Hazard Analysis Study reports must be maintained for the life of the process.

– Including recommendation resolution.– Sign In Sheets.– Piping Diagrams from the date of the study.– Team Leader Qualifications.– Methodology.– Regulatory Invites as applicable.

Process Hazard Analysis RevalidationsWhat Can Be Learned…

• Safety improvements.• Operability improvements.• Operator “wish list”.• Engineering and administrative controls in

place for handling releases or potential releases.

• Clarify emergency response / action procedures.

• Operator training program.• Alternative Release Scenarios.