Revised Outer Continental Shelf Lease Exploration Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. May 2011 

Appendix N 

H2S Contingency Plan for M/V Noble Discoverer

 
Revised Outer Continental Shelf Lease Exploration Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. May 2011 

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Shell Gulf of Mexico Inc. 1

CHUKCHI SEA REGIONAL 

HYDROGEN SULFIDE (H2S)

CONTINGENCY PLAN

Shell Gulf of Mexico, Inc. 

Exploration Drilling & Evaluation Operations 

Rig: Noble DISCOVERER

February 2011 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 2 May 2011 

THIS PAGE INTENTIONALLY LEFT BLANK 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 3 May 2011 

TABLE OF CONTENTS 

I. DEFINITIONS 7 

II. INTRODUCTION 7 

III. OPERATING PHILOSOPHY 8 

 

IV. H2S and SO2 Properties 8 

A. Hydrogen Sulfide 8 

B. Sulfur Dioxide 11 

V. H2S TRAINING 14 

VI. SAFETY EQUIPMENT 16 

 A. Muster Areas 16 

 B. Safe Briefing Areas 16 

 C. Wind Direction Indications 16 

 D. Danger Signs 16 

 E. Operating Condition Signs 17 

 F. H2S Detectors and Alarms 17 

 G. Flare Line Piping 18 

 H. H2S Service Equipment 19 

 I. H2S Scavengers 19 

 J. Breathing Air Cascades and Manifolds 19 

 K. Safety Equipment 20 

 L. Metallurgical Properties of Equipment 20 

 M. Fans 21 

N. Forced Air Control Switches 21 

O. Attending Vessels 21 

VII. NORMAL OPERATING PROCEDURES 21 

 A. Emergency Phone List 21 

 B. Safety Equipment 22 

 C. Supplied Air Breathing Equipment 22 

 D. Training 22 

 E. Testing 23 

 F. Reporting Aboard Drillship 23 

 G. Breathing Air Equipment 23 

 H. Drills 24 

 I. Spare Equipment 24 

 J. Spot Checks 24 

 K. Wind Direction 24 

 L. Welding Prohibition 24 

VIII. OPERATING CONDITIONS – CLASSIFICATIONS 25 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 4 May 2011 

 A. Possible Hazardous Conditions 25 

 B. Condition I 25 

 C. Condition II 26 

 D. Condition III 27 

 

IX. H2S EMERGENCY PROCEDURES 28 

 A. Emergency Procedures for Condition I 28 

 B. Emergency Procedures for Condition II and III 30 

 C. Evacuation Procedures 32 

X. SPECIAL OPERATIONS 33 

A. Other Operations 33 

B. Monitor Observation During Specific Operations 33 

XI. WELL CONTROL 33 

 A. Trip Gas 33 

 B. All Kicks 34 

XII. LOST CIRCULATION 34 

 

XIII. PARTIAL EVACUATION PROCEDURE 34 

XIV. RESPONSIBILITIES AND DUTIES – H2S 34 

 A. All Personnel 34 

 B. Shell Drilling Foreman 34 

 C. Vessel Master/ Noble Drilling Superintendent 35 

D. H2S Safety Technicians 36 

E. Dispatcher/ Radio Operator 37 

F. Noble Toolpusher/ Driller 37 

G. Mudlogger 38 

H. Mud Engineer 38 

I. H2S Flaring 38 

XV. PROCEDURE FOR INFORMING PERSONNEL OF THE 39 

“H2S CONTINGENCY PLAN” 

A. Aboard Drillship 39 

B. Aboard Support Vessels 39 

XVI. SEARCH AND RESCUE TEAMS 39 

 A. Primary Goal 39 

 B. Critical Areas 39 

 C. Unconcious Victims 40 

 D. Purging the Area 40 

 E. Procedures and Drills 40 

 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 5 May 2011 

APPENDIX 43 

SECTION A: Procedures 

A-1 Well Control Procedures 44 

A-2 Lost Circulation Procedure 46 

A-3 Mud Treating 47 

SECTION B: General Information 

B-1 Toxicity of Various Gases 50 

B-1 Properties of Gases 50 

B-1 Treatment for H2S Poisoning 51 

B-1 SO2 Effects 52 

B-1 Contingency Plan Memorandum of Understanding 53 

B-2 Breathing Air Equipment Drills for On-Duty Personnel 54 

B-3 Breathing Air Equipment Drills for Off-Duty Personnel 56 

B-4 Hydrogen Sulfide Training Curriculum and Forms 58 

 Standard Fit Test Form 60 

 Training Roster Form 61 

B-5 Emergency Telephone Listing 62 

B-6 Key Personnel to Remain Aboard During Partial Evacuation 64 

SECTION C: Equipment List and Checklists 

C-1 H2S Equipment List for Rig and Vessels as applicable 65 

C-2 Noble Drilling Superintendent Checklist: Safety Equipment 67 

C-3 Safety Equipment Checklist- Mudlogger 69 

C-4 Safety Equipment Checklist- H2S Safety Technician 70 

C-5 Safety Equipment Checklist- Mud Engineer 71 

C-6 Shell Checklist of Routine Duties 72 

SECTION D: Rules and Regulations 

D-1 30 CFR 250-490 Hydrogen Sulfide Regulations 73 

D-2 MMS PINC list for H2S 87 

D-3 29 CFR - CHAPTER XVII - PART 1910.134 Respiratory Protection 114 

SECTION E: Rig Drawings 164 

94731-341-001 GAS DETECTION ONE LINE 

94731-345-001 BREATHING AIR ONE LINE 1 OF 2 

94731-345-002 BREATHING AIR ONE LINE 2 OF 2 

94731-345-003 QUARTERS MAIN DECK EQUIPMENT LAYOUT 

94731-345-004 QUARTERS POOP DECK EQUIPMENT LAYOUT 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 6 May 2011 

94731-345-005 QUARTERS BOAT DECK EQUIPMENT LAYOUT 

94731-345-006 QUARTERS BRIDGE DECK EQUIPMENT LAYOUT 

94731-345-007 QUARTERS/BRIDGE DECK EQUIPMENT LAYOUT 

94731-345-008 HOUSE TOP EQUIPMENT LAYOUT 

94731-345-009 FORWARD BRIDGE EQUIPMENT LAYOUT 

94731-345-010 MAIN DECK BOW EQUIPMENT LAYOUT 

94731-345-011 DRILL FLOOR EQUIPMENT LAYOUT 

94731-345-012 SHAKERS EQUIPMENT LAYOUT 

94731-345-013 CEMENT UNIT & MOON POOL EQUIPMENT 

LAYOUT 

94731-345-014 SACK ROOM, PUMP ROOM & MUD PIT 

EQUIPMENT LAYOUT 

94731-345-015 SCR & ENGINE ROOM EQUIPMENT LAYOUT 

94731-345-016 CRANES EQUIPMENT LAYOUT 

 

 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 7 May 2011 

I. DEFINITIONS 

 Bureau of Ocean Energy Management, Regulation and Enforcement (BOEMRE 

or BOE)-formerly the Minerals Management Service (MMS)

 H2S Absent- previous drilling, testing, logging and sampling in the area or in 

equivalent stratigraphic units have confirmed the absence of H2S in the area to 

be drilled

 H2S Present- previous drilling, testing, logging and sampling have confirmed the 

presence of H2S in concentrations and volumes that could potentially result in 

atmospheric concentrations of 20 ppm or more of H2S

 H2S Unknown- the designation of a zone or geologic formation where neither the 

presence nor absence of H2S has been confirmed

 Application for Permit to Drill (APD)- forms and supporting information, including 

a request for a classification of an area with respect to H2S (absent, present or 

unknown), submitted to the BOE in advance of the initiation of drilling operations.

 Request for classification- a letter containing additional data indicating that a 

different H2S classification is required to replace the original classification made 

by the BOE from data filed with the APD.

 H2S Contingency Plan- a set of procedures and practices submitted to the BOE 

Regional Supervisor Field Operations (RS/FO) prior to the initiation of operations 

outlining steps to deal with H2S hazards in H2S Present or H2S Unknown 

classified areas. 

II. INTRODUCTION 

This plan was developed because of the potential hazards involved when performing 

operations in formations that may contain H2S. It was written in compliance with the 

rules and regulations of the BOE in Section 30, Code of Federal Regulations, Part 250, 

Subpart 490. This plan specifies precautionary measures, safety equipment, 

emergency procedures, responsibilities, and duties pertaining to drilling operations in 

potential H2S- bearing formations. 

There will be one evacuation vessel (to be determined) stationed near the M/V Noble

Discoverer (Discoverer) at all times. The attending evacuation vessel will be equipped 

with a breathing air cascade system and an H2S detection/alarm system. Specific 

evacuation procedures are discussed in Section IX, H2S Emergency Procedures. 

To be effective, this plan requires the cooperation and effort of each individual 

participating in drilling operations in a well with the potential of releasing H2S. Each 

individual should know his/her responsibilities and duties in regard to normal operations 

and emergency procedures. Personnel should thoroughly understand and be able to 

use, at a moment’s notice, all safety equipment on board the rig. They should 

familiarize themselves with the location of all safety equipment and see that their 

individually assigned equipment is properly stored, easily accessible, and routinely 

maintained. The ideas and suggestions of each individual involved in the drilling or 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 8 May 2011 

abandonment of a potential sour gas well are highly welcomed and are an asset for 

providing the safest working conditions possible. 

This H2S Contingency Plan will go into effect upon entering the Chukchi Sea. Safety 

equipment will be installed on the vessel and will be functional and tested prior to 

departure from Dutch Harbor. Personnel will be trained and competent to carry out the 

provisions of the plan. 

Shell Gulf of Mexico, Inc. (Shell) intends to make every effort to provide adequate 

safeguards against harm to persons both on location and in the immediate vicinity from 

the effects of hydrogen sulfide if released into the atmosphere. 

III. OPERATING PHILOSOPHY 

Formations in the Chukchi Sea may or may not contain H2S. The BOEMRE, in keeping 

with the provisions of 30 CFR 250.490, has classified the Chukchi Sea as H2S 

UNKNOWN. 

Shell is taking every precaution to protect the people and the environment in the unlikely 

event that H2S is encountered. The Discoverer will be fitted with all of the equipment 

and safety devices as required by code and all personnel who will be onboard the 

vessel during the drilling wells in the Chukchi Sea will be properly trained and drilled as 

required by code. 

IV. H2S and SO2 Properties 

A. HYDROGEN SULFIDE 

1. Physical Properties 

CHEMICAL NAME Hydrogen Sulfide 

CAS NUMBER 7783-06-4 

SYNONYMS Sulfurated hydrogen, hydrosulfuric acid, dihydrogen sulfide 

CHEMICAL FAMILY Inorganic sulfide 

CHEMICAL FORMULA H2S 

NORMAL PHYSICAL 

STATE 

Colorless gas, vapor density at 59oF (15oC) at 1 

atmosphere = 1.1895 SG 

IGNITION 

TEMPERATURE 

500oF (260oC) 

BOILING POINT -76oF (-60.2oC) 

MELTING POINT -117.2oF (-82.9oC) 

FLAMMABLE LIMITS 4.3 - 46% by volume in air 

SOLUBILITY Soluble in water and oil; solubility decreases as the fluid 

temperature increases. 

COMBUSTIBILITY Burns with a blue flame to produce sulfur dioxide. 

WARNING 

PROPERTIES

H2S has an extremely unpleasant odor, similar to the smell 

of rotten eggs, and is easily detected at low concentrations 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 9 May 2011 

(0.13 ppm). Due to the paralyzing effect the gas has on 

the olfactory nerve, THE SENSE OF SMELL IS NOT AN 

ACCEPTABLE INDICATOR. 

2. Exposure Limits 

The Occupational Safety and Health Administration (OSHA) permissible 

exposure limit (PEL) for H2S is 10 ppm for eight-hour time-weighted 

average (TWA8) or 15 ppm for short term exposure limit (STEL) as 

averaged over 15 minutes, per 29 CFR Part 1910.1000, “Toxic and 

Hazardous Substance,” U.S. Department of Labor, Occupational Safety 

and Health Administration. Recently, the American Conference of 

Governmental Industrial Hygienists (ACGIH) reduced their recommended 

exposure limits for H2S. ACGIH voted to reduce the 8-hour time-weighted 

average Threshold Limit Value (TLV-TWA8) for H2S from 10 to 1 ppm and 

their Short Term Exposure Limit (TLV-STEL) from 15 to 5 ppm. ACGIH 

TLVs reflect industry consensus on the level of exposure a typical worker 

can experience without unreasonable risk of disease or injury. These limits 

are voluntary standards and are not enforceable where OSHA’s PELs and 

regulatory concentration limits are. Most currently available H2S 

measuring and monitoring equipment is not accurate in the 1 ppm range. 

The National Institute for Safety and Health (NIOSH) considers a 

concentration of 100 ppm H2S to be immediately dangerous to life and 

health (IDLH). For purposes of this contingency plan, the concentration 

values listed in 30 CFR 250.490 will be used for detection, alarm and 

action limits. 

3. Physiological Effects 

When a person inhales H2S, the gas goes directly through the lungs and 

almost instantaneously into the bloodstream. Through an oxidation 

reaction, H2S is broken down in the body into a harmless compound. 

However, if the individual breathes in large quantities of H2S, the oxidation 

process lags behind the intake rate of the gas. The unoxidized H2S builds 

up in the blood and the individual becomes poisoned. The nerve center in 

the brain which controls breathing is paralyzed and the respiration process 

is halted. Death is caused by asphyxiation at the cellular level. 

Susceptibility to H2S poisoning is dependent on four factors: 

 Duration: 

The length of time the individual is exposed to non-lethal 

concentrations of H2S. Longer exposure to low H2S concentrations 

has a desensitizing effect on the sense of smell. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 10 May 2011 

 Frequency: 

How often the individual is exposed to H2S. Closely repeated shortterm exposures at low concentrations may lead to chronic irritation 

of the eyes, nose and throat and headaches, dizziness and upset 

stomach. Even at concentrations under 5 ppm, metabolic changes 

and increased anxiety have been reported in people who are 

exercising. 

 Intensity:

The concentration of the exposure. The higher the concentration, 

the greater the physiological effect. 

 Individual Susceptibility: 

Dependent on the individual’s physiological make-up. Studies 

show that symptoms of H2S exposure vary considerably because of 

individual physiological make-up. Personnel may be highly 

susceptible to H2S due to health reasons such as lung diseases, 

and the individual’s mental state such as anxiety attacks. 

4. H2S Toxicity Table 

The following table shows approximate values for guidance. 

CONCENTRATIONS OF H2S IN AIR 

% by 

Volume 

ppm by 

Volume 

Grains per 

100 std. 

cubic feet 

Milligrams 

per cubic 

meter 

Typical Characteristics 

Regarding H2S Exposure 

0.000013 0.13 0.008 0.18 Obvious and unpleasant odor 

generally at 0.13 ppm and quite 

noticeable at 4.6 ppm. As the 

concentration increases, the sense of 

smell fatigues and the gas can no 

longer be detected by odor. Often 

referred to as the Lower Odor 

Threshold level. 

0.001 10 0.63 14.41 Unpleasant odor. Possible eye 

irritation. OSHA PEL-TWA8 (see 29 

CFR Part 1919.1000, Table Z-1A) 

0.0015 15 0-94 21.61 OSHA STEL averaged over 15 min. 

0.002 20 1.26 28.83 Burning sensation in eyes and 

irritation of the respiratory tract after 

one hour or more of exposure. BOE 

requires audio and visual alarms and 

other safety measures to be employed 

when H2S is present at or above this 

concentration (30 CFR 250.490). 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 11 May 2011 

0.005 50 3.15 72.07 Loss of sense of smell after about 15 

or more minutes exposure. Exposure 

over one hour may lead to headache, 

dizziness, and or staggering. 

Pulmonary edema has been reported 

following extended exposure to 

greater than 50 ppm. Exposure at 50 

ppm or greater can cause serious eye 

irritation or damage. 

0.01 100 6.3 144.14 Coughing, eye irritation, loss of sense 

of smell after 3-5 minutes. Altered 

respiration, pain in the eyes, and 

drowsiness after about 15-20 minutes, 

followed by throat irritation after one 

hour. Upper odor threshold. 

Prolonged exposure results in an 

increase in the severity of these 

symptoms. Concentration considered 

by NIOSH to be IDLH ( See “NIOSH 

Pocket Guide to Chemical Hazards”, 

5th edition.) 

0.03 300 18.9 432.4 Maximum concentration from which 

one could escape within 30 minutes, 

without experiencing impairing or 

irreversible health effects if not 

breathing supplied air. 

0.05 500 31.49 720.49 Unconsciousness after short 

exposure, cessation of breathing if not 

treated quickly. Dizziness, loss of 

sense of reasoning and balance. 

Victim will probably need prompt 

cardiopulmonary resuscitation (CPR). 

0.07 700 44.08 1008.55 Unconscious quickly. Breathing will 

stop and death will result if not 

rescued promptly. Artificial ventilation 

and/or CPR needed immediately. 

0.10 1000 62.98 1400.98 Unconscious at once. Permanent 

brain damage or death may result. 

Rescue promptly and apply artificial 

ventilation and/or CPR. 

B. SULFUR DIOXIDE

One method by which Sulfur Dioxide (SO2) is formed can be the result of 

burning H2S. SO2 is a colorless, non-flammable gas, having a pungent odor 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 12 May 2011 

and characterized by an acid taste at very low concentrations. SO2 in 

concentrations of 3-5 ppm in air is an intense irritant to humans and therefore 

readily detectable. 

1. Physical Properties 

CHEMICAL NAME Sulfur Dioxide 

CAS NUMBER 7446-09-05 

SYNONYMS Sulfurous Anhydride, Sulfurous Oxide 

CHEMICAL FAMILY Inorganic 

CHEMICAL FORMULA SO2

NORMAL PHYSICAL STATE 

Colorless gas appreciably heavier than air. Vapor 

density at 32oF (0oC) and 1 atmosphere = 2.26 SG 

BOILING POINT 14oF (-10.0oC) 

FLAMMABLE LIMITS Non-flammable 

SOLUBILITY Readily soluble in water and oil; solubility decreases 

as the fluid temperature increases. 

ODOR AND WARNING 

PROPERTIES

Sulfur dioxide has a pungent odor associated with 

burning sulfur.

2. Exposure Limits 

The OSHA established the PEL-TWA8 for SO2 at 2 ppm, or the STEL of 5 

ppm as averaged over 15 minutes (see 29 CFR Part 1910.1000). ACGIH 

recommends 2 ppm as the TWA8 for SO2. 

3. Physiological Effects 

 Acute Toxicity: 

Inhalation at certain concentrations can lead to irritation, injury or 

death. Exposure at 50 ppm rapidly causes irritation to the mucous 

membranes of the nose and throat, coughing, reflex bronchiconstriction, and breathing congestion as the SO2 oxidizes and 

hydrolyzes to sulfuric acid (H2SO4). This SO2 concentration will not 

be tolerated by most persons for more than 15 minutes. The 

severely irritating effect of the gas makes it unlikely that any person 

would be able to voluntarily remain in a contaminated atmosphere 

for long periods. The most common cause of sulfur dioxide 

poisoning occurs when a person is either unconscious or trapped 

and unable to move. Acute reactions to exposure to high 

concentrations are conjunctivitis, nausea, vomiting, abdominal pain, 

and sore throat followed by bronchitis, pneumonia and/or 

complaints of weakness for a period of weeks. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 13 May 2011 

 Chronic Toxicity: 

Reports indicated that prolonged exposures to SO2 may contribute 

to alterations in the sense of smell and taste, shortness of breath 

on exertion, and a higher frequency of respiratory infections 

compared to unexposed persons. SO2 in the work environment 

may “possibly” enhance the suspected carcinogenic effect of 

arsenic and other cancer agents. 

4. SO2 Toxicity Table 

NOTE: Any pre-existing chronic respiratory impairment must be 

considered in regard to job placement since these conditions can be 

aggravated by exposure to sulfur dioxide. 

CONCENTRATIONS OF SO2 IN AIR 

% by 

Volume 

PPM by 

Volume 

Grains per 

100 std. 

cubic feet 

Milligrams 

per cubic 

meter 

Typical Characteristics 

Regarding SO2 Exposure 

0.0001 1 0.012 2.71 Pungent odor, may cause respiratory changes

0.002 2 0.24 5.42 OSHA PEL-TWA8 (see 29 CFR Part 

1910.1000, Table Z-1A) and ACGIH 

recommended TLV. 

0.0005 5 0.59 13.50 Burning eyes, breathing irritation and minor 

throat irritation. OSHA STEL averaged over 

15 minutes (see 29 CFR Part 1910.1000, 

Table Z-1A). 

0.0012 12 1.42 32.49 Throat irritation, cough, constriction in chest, 

watering eyes, and nausea. 

0.010 100 12.00 271.00 This is the maximum concentration from 

which one could escape within 30 minutes, 

without experiencing impairing or irreversible 

health effects without supplied breathing air. 

Concentration considered IDLH (see “NIOSH 

Pocket Guide to Chemical Hazards”, 5th 

edition). 

0.015 150 17.76 406.35 Extreme irritation. Can be tolerated for only a 

few minutes. 

0.05 500 59.2 1354.50 Causes a sense of suffocation, even with the 

first breath. Rescue promptly and apply 

artificial ventilation and/or CPR. 

0.10 1000 118.4 2708.99 Death may result unless rescued promptly. 

Apply artificial ventilation and/or (CPR) 

immediately. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 14 May 2011 

V. H2S TRAINING 

At the docks and on the Discoverer; each individual will be asked if they have been 

cleared by a physician to use a respirator. This requirement will be the responsibility of 

each company or individual before coming aboard the drillship. 

Each person will be informed on the restrictions of having beards and wearing contact 

lenses. They will also be informed of the availability of spectacle kits. 

The safety program is outlined in the H2S Contingency Plan. This plan will be available 

on the rig. Each individual will be briefed on the H2S Contingency Plan and sign the 

“Contingency Plan Memorandum of Understanding”. 

After the H2S equipment is rigged up, all personnel will be H2S trained and put through a 

drill. Any deficiencies will be corrected. 

Training Completion cards are good for one year and will indicate date of training 

completion or expiration. Personnel previously trained on another facility and visiting 

the Discoverer must attend a “supplemental briefing” on H2S equipment and procedures 

before beginning duty. Visitors without current H2S certification who remain on the 

facility more than 24 hours must receive full H2S training given all crew members. A 

“supplemental briefing” will include but not be limited to the location, use and donning of 

an assigned respirator, familiarization with safe briefing areas, alarms with instruction on 

responsibilities in the event of a release and hazards of H2S and SO2. 

Topics for full H2S training shall include, but not limited to the following: 

A. Brief Introduction of H2S 

1. Slide or VCR presentation (If available) 

2. H2S Material will be distributed 

3. Re-emphasize the properties, toxicity, and hazards of H2S 

4. Source of SO2

B. H2S Detection 

1. Description and sensitivity of H2S sensors 

2. Description of warning system (how it works and its location) 

3. Actual location of H2S sensors 

4. Instruction on use of pump type detector 

5. Use of card detectors, ampoules, or dosimeters 

6. Use of combustible gas detector 

7. Other personnel detectors 

8. Alarm conditions I, II or III (10 ppm, 20 ppm or 50 ppm) 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 15 May 2011 

9. SO2 (2 ppm and 5 ppm) 

C. H2S Protection 

1. Types of breathing apparatus provided (30-minute SCBA & SKA PAK with 

voice diaphragms for communication) 

2. Principle of how breathing apparatus works 

3. Demonstration on how to use breathing apparatus 

4. Location of breathing apparatus 

D. Cascade System 

1. Description of a typical cascade system 

2. How the system works 

3. Cascade locations on the drillship with reference to briefing areas 

4. How to use cascade system (with SKA PAKS & refill) 

5. Importance of wind direction and location of windsocks 

6. Purpose of compressor/function 

E. H2S Rescue and First Aid 

1. Importance of wind direction 

2. Safe briefing area 

3. “Buddy” System 

4. H2S symptoms 

5. Methods of rescue 

F. Hands on Training 

1. Donning/familiarization of SCBA 

2. Donning/familiarization of Escape/Work unit 

3. Familiarization with cascades 

4. Use of O2 resuscitator 

5. Alarm conditions – upwind briefing areas, etc. 

6. Duties and responsibilities of all personnel 

7. Procedures for evacuation 

8. Search and Rescue teams 

G. Certification 

A. Testing on material covered 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 16 May 2011 

VI. SAFETY EQUIPMENT 

A summary of procedures and equipment that will be operational at compliance depth is 

as follows: 

A. Muster Areas 

The AFT Muster area will be in the Galley. The FWD Muster area will be in 

the Forward Foyer which is located in the bow area of the ship. Personnel 

AFT of the moonpool will use the AFT Muster area; personnel FWD of the 

moonpool will use the FWD Muster area. 

B. Safe Briefing Areas 

Two areas will be designated as “SAFE BRIEFING AREAS”. The AFT Briefing 

Area will be located on the AFT Main Deck below the Helicopter Deck. The 

FWD Briefing Area will be located on the Main Deck Bow. Personnel AFT of 

the moonpool will use the AFT Briefing Area; personnel FWD of the moonpool 

will use the FWD Briefing Area. Drawings of the rig are included in the 

Appendix. 

C. Wind Direction Indicators 

Windsocks will be installed on the vessel. They will be positioned as to be 

seen from any location on the main deck, rig floor and heliport. 

D. Danger Signs 

Four 4’ x 8’ danger signs will be displayed from all sides of the vessel in a 

manner visible to watercraft and aircraft. The signs will be yellow with the 

following warning painted in 12” high black, block lettering. 

DANGER POISONOUS GAS 

 HYDROGEN SULFIDE 

DO NOT APPROACH IF RED LIGHTS ARE FLASHING

Signs are worded as per the regulation. Signs are photo luminescent. The 

danger signs will be displayed at compliance depth. If the H2S concentration 

exceeds 20 ppm at the surface, four 2’ x 3’ red light panels will be flashing 

visible to marine traffic, aircraft & personnel on the drillship. Red flags will not 

be used; red lights will. All signs will be illuminated under conditions of poor 

visibility and at night. Signs will be posted indicating the safe briefing areas 

and Condition I, II and III signals, as designated in Section B-1 of the 

Appendix. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 17 May 2011 

E. Operating Condition Signs 

Operating Condition posters indicating Condition I, II, and III will be located in 

the following areas: 

1. Each level of the living quarters 

2. Rig floor 

3. Mud pit area 

4. Engine room area 

5. Work areas on the Main Deck 

6. Mud pump area 

7. Galley 

8. Moonpool 

9. Transit room 

10. Recreation room 

11. Shale shaker 

F. H2S Detectors and Alarms 

The gas detection control panel will be located in the Emergency Response 

Room. Annunciator panels will be located in the following locations: 

1. Company representative office 

2. Toolpusher’s office 

3. Toolpusher’s quarters 

Continuous monitoring type H2S detectors, capable of sensing a minimum of 

10 ppm H2S in air, will be located at each of the following points: 

1. Rig floor/ Driller’s station 

2. Rig floor/ bell nipple 

3. Mud return line/ gumbo box 

4. Trip tank 

5. Shale shaker 1 

6. Shale shaker 2 

7. Possum Belly 

8. Active pit 

9. Pump room 

10. Sack room 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 18 May 2011 

11. Cement unit/Dive control area 

12. Bridge Intake 

13. Aft Quarters 

14. Forward Quarters 

15. Quarters Intake HVAC 

16. Moonpool 

17. Engine room intake 

All detectors will be tested once every 24 hours. If tests are not within 2 ppm 

or 10 percent, whichever is greater, then that sensor will be recalibrated. 

Automatic H2S Alarms (Visible and Audible) will be located at the following 

points: 

1. Rig floor 

2. Sack room 

3. Active pit 

4. Shaker area 

5. Pump room 

6. Engine room 

7. Cement unit /Dive control area 

8. Mud logging unit 

9. Navigation Bridge Deck (2) 

10. Quarters Bridge Deck (3) 

11. Quarters Boat Deck (2) 

12. Quarters Poop Deck (2) 

13. Quarters Main Deck (2) 

Alarms will be suitable for the electrical classification of the area where they 

are installed. An alarm station will be located in the control house. Upon 

verification of the alarm, the ship’s gas alarm system will be engaged. 

G. Flare Line Piping 

Prior to compliance depth, the degasser and the mud-gas separator will be 

rigged so the gas can be flared if H2S is encountered in concentrations equal 

to, or exceeding, 20 ppm. A remote electronic ignition device will be available 

along with an alternate backup method for igniting the flare (handheld flare 

gun). The Flare outlet must be a diameter that allows easy non-restricted flow 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 19 May 2011 

of gas. SO2 monitor readings will be taken using a portable instrument on an 

hourly basis and logged in reports. 

Blowout Prevention Equipment- The blowout preventers, integral choke and 

kill lines, and surface manifold are designed for H2S service in case it 

becomes necessary to circulate a kick. 

H. H2S Service Equipment 

N/A (Refer to 30 CFR 250.490 (p) which specifies that this equipment is 

required for areas classified as “H2S PRESENT” or “H2S UNKNOWN”) 

I. H2S Scavengers 

A supply of zinc oxide, or an equivalent, will be stored aboard the rig in case 

the mud becomes contaminated with H2S. A detailed mud treating procedure 

is given in Section A-3 of the Appendix. After reaching compliance depth, a 

sufficient volume of zinc oxide will be maintained aboard the rig to treat the 

entire system twice with two pounds per barrel (ppb). If water-based drilling 

fluids are used and ambient air sensors detect H2S either the Garrett-GasTrain test or comparable test for soluble sulfides must immediately be 

conducted to confirm the presence of H2S. 

J. Breathing Air Cascade System (BACS) consists of the following: 

1. Grade D/E breathing air compressor 

2. Breathing air cascade storage cylinders 

3. Interconnection and distribution hose or tubing 

4. Distribution panels 

5. Manifolds 

 The BACS utilizes central storage cascade cylinders and a closed loop high 

pressure cascade to supply breathing air to the distribution panels located 

about the vessel. Distribution panels reduce the high pressure air to working 

pressure for distribution to the manifolds. 

1. Safe Briefing Areas, Forward and Aft (12 ea. 12-outlet and one 6-outlet) 

2. Shale shaker area (2 ea. 3-outlet) 

3. Drill floor (2 ea.12-outlet) and 2 ea. 8-cylinder cascades 

4. Derrick (3-outlet) 

5. Racking cabin (3-outlet) 

6. Pump room (6-outlet) 

7. Pit room (6-outlet) 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 20 May 2011 

8. Sack room (6-outlet) 

9. Mud logging unit (6-outlet) 

10. Moon Pool (6-outlet) 

11. Bridge (6-outlet) 

12. Dive Deck Location (6-outlet) 

13. Dive Control Van (6-outlet) 

14. Dive Launch & Recovery System (LARS) (6-outlet) 

There will also be a breathing air cascade system located on a standby vessel 

to support an evacuation of all personnel aboard the Discoverer and vessel 

crew aboard the standby vessel. The vessel will make optimum use of staying 

upwind during H2S operations. Breathing air compressors will be located near 

the Briefing Areas for refill. All 444 ft3 (cu ft) breathing air cylinders will be 

labeled: Safe Breathing Air; Grade D/E Breathing Compressed Air for Human 

Use. 

K. Safety Equipment 

Chalkboards and/or notepads for communication are located on the rig floor, 

shale shaker area, the cement room, and the pump room. Bullhorn, safety 

litter, first aid kits, resuscitators, safety harnesses and voice transmission 

devices will be kept in the ship’s infirmary and/or Shell’s gang box. The list of 

safety equipment (including breathing air equipment, resuscitators, H2S and 

SO2 detectors, and explosion meters, flare guns, etc.) are listed in Section C of 

the Appendix. 

L. Metallurgical Properties of Equipment 

 

N/A (Refer to 30 CFR 250.490 (p) which specifies that this equipment is 

required for areas classified as “H2S PRESENT” or “ H2S UNKNOWN”) 

When operating in a zone with H2S present, equipment will be used that is 

constructed of materials with metallurgical properties that resist or prevent 

sulfide stress cracking, chloride stress cracking, hydrogen-induced cracking 

and other failure modes. The following will be in effect: 

 Tubulars and other equipment, casing, tubing, drill pipe, couplings, 

flanges, and related equipment should be designed for H2S service. 

 Temporary downhole well security devices such as retrievable packers 

and bridge plugs should be designed for H2S service. 

 Wireline lubricators, which may be exposed to fluids containing H2S, 

must be of H2S-resistant materials. 

 H2S-resistant materials will be used for all elastomer seals. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 21 May 2011 

 Deck drains must be equipped with traps or similar devices to prevent 

the escape of H2S gas into the atmosphere. 

 Precautions will be taken to eliminate sealed voids in piping designs, 

such as slip on flanges, reinforcing pads, which can be invaded by 

atomic hydrogen when H2S is present. 

M. Fans 

Movable ventilation devices will be provided in work areas. Devices will be 

capable of dispersing H2S or SO2 vapors away from working personnel. Areas 

may include rig floor, mud pit, shale shake, and cement unit areas. All 

ventilation devices will be explosion proof. 

N. Forced Air Control Switch 

All forced air systems will be shut down upon detection of 20 ppm or greater 

(mud logging unit, quarters, and any other forced air control switches should 

be shut off.) 

O. Attending Vessels 

Vessels that are stationed overnight alongside the Discoverer will be 

equipped with an H2S detection system that activates audible and visual 

alarms when the concentration of H2S in the atmosphere reaches 20 ppm. 

This requirement does not apply to vessels that are not stationed alongside 

overnight or to vessels positioned upwind and at a safe distance from the 

facility in accordance with the positioning procedure described in the approved 

H2S Contingency Plan. 

Attending vessels will be identified prior to the commencement of drilling 

operations and listed in an updated contingency plan. Time along side the 

Discoverer will be in compliance with the Air Permit issued by the 

Environmental Protection Agency. 

VII. NORMAL OPERATING PROCEDURES 

A. Emergency Phone List 

Lists of emergency phone numbers will be sent to the drillship and should be 

posted at the following locations: Emergency Room, Radio Room, Drillship 

Master’s office, Noble Drilling Superintendent’s office, Shell Drilling Foreman’s 

office, Shell SIMOPS Coordinator’s office and all Support Vessels. Copies will 

be available in the Shell and Noble Anchorage and Houston offices as well. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 22 May 2011 

B. Safety Equipment 

All safety equipment and H2S related hardware must be set up as outlined 

under Section V “Safety Equipment”. All safety equipment must be inspected 

routinely, paying particular attention to resuscitators and breathing air 

equipment. SCBAs will be pressure-demand-type with hoseline capability 

rated for at least 30 minute duration. 

C. Supplied Air Breathing Equipment 

All personnel on board will be assigned breathing air equipment and, if 

needed, lead-acetate spot check. Shell and rig contractor personnel required 

to work in the following areas will be provided with work/escape type air line 

equipment with 10-minute escape duration. These units are in addition to their 

assigned 30-minute rated units. 

1. Rig floor 

2. Mud pit area 

3. Mud pump room 

4. Sack storage area 

5. Cementing area 

6. Engine room 

7. Shale shaker area 

8. Mud logging unit 

9. Dive Launch and Recovery System (LARS) 

10. Dive control van 

11. Decompression chamber 

12. Dive deck work area 

13. Bridge 

D. Training 

Prior to the initiation of drilling operations, all personnel must be thoroughly 

trained in the use of breathing air equipment, emergency procedures, 

responsibilities, and first aid for H2S victims. All personnel when coming on 

board will immediately receive H2S training or a supplemental briefing. The 

H2S Safety Technician must keep a list of all who have been through the 

special training programs on board the rig. 

Documentation of training must be provided by the service company. All 

personnel will be briefed on the Contingency Plan and sign a copy of the 

“Contingency Plan Memorandum of Understanding”, in Section B-1 of the 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 23 May 2011 

Appendix. This document summarizes the steps to be taken during the three 

conditions under which the drillship may operate. It lists general information 

about toxic gases, explains the physiological effects of H2S, operating 

conditions as defined by the H2S contingency plan, and informs each reader of 

his general responsibilities concerning safety equipment and emergency 

procedures. 

E. Testing 

Below compliance depth the H2S detection system will be tested every 24 

hours under normal conditions. The H2S detectors will be calibrated weekly. In 

the event that H2S is detected, or when drilling a zone containing H2S, the 

units will be tested at least once every 24 hours. The time and results of each 

test or calibration will be logged by the H2S Technician and reported each day 

to the Shell Drilling Foreman. The Shell Drilling Foreman will ensure that the 

H2S detection equipment calibrations and tests are recorded on the IADC 

Daily Drilling Report Form and Morning Report. In the event that an H2S 

detector does not test successfully, operations will cease until: 

 The detector is repaired 

 Approval to proceed is received from the Shell Drilling Foreman, as per 

the 30 CFR 250.490. 

F. Reporting Aboard the Drillship 

When boarding the vessel from either boat or helicopter, all personnel, without 

exception, must proceed directly to the H2S Safety Technician for assignment 

of breathing air equipment and, if needed, ampoules or equivalent H2S 

detector. An instruction and orientation briefing will also be held, if needed 

(See section on training requirements). The H2S Safety Technician will be 

responsible for assigning equipment to the individuals and instructing them in 

its use. 

G. Breathing Air Equipment 

Each person aboard the drillship will be instructed in the use of breathing air 

equipment until supervisory personnel are satisfied that each is capable of 

using the equipment. The training must include all additional personnel that 

are allowed aboard the drillship during drilling operations. 

After familiarization, each on-duty rig and roustabout crew must perform a 

weekly drill with breathing equipment. The drill will include such topics as 

securing the breathing air equipment, putting it on, and working for a short 

period, doffing the equipment, cleaning and storing it for future use. A record 

should be kept of the crews drilled and the date. A complete “BREATHING 

AIR EQUIPMENT DRILL” procedure is given in Section B-2 of Appendix. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 24 May 2011 

H. Drills 

Along with normal weekly fire drills and safety meetings, weekly breathing air 

equipment drills and H2S training sessions must be held for all personnel and 

a record of attendance must be kept. Visitors will be given a supplemental 

briefing even if they hold a valid H2S card. However, if the visitor stays more 

than 24 hours, then full H2S briefing and orientation will be required for the 

visitor. An explanation of these drills and training sessions and a list of what 

they include are provided in Section B-3 of the Appendix. 

I. Spare Equipment 

Rig crews and service company personnel should be aware of the location of 

spare breathing air bottles, resuscitation equipment, portable fire 

extinguishers, and H2S detectors. Knowledge of the location of H2S detector 

monitors is vital to understanding the “emergency conditions”. In addition, key 

personnel must be trained in the use of the resuscitator and H2S detector 

ampoules. 

J. Spot Checks 

H2S spot checks shall be available for use by working personnel. After H2S 

has been initially detected by any device, periodic inspections of all areas of 

poor ventilation shall be made with a portable H2S detector instrument. 

K. Wind Direction 

All personnel on the location shall become “wind conscious” and must be 

aware of the direction of the prevailing winds at all times. They should 

remember that H2S is heavier than air and will collect in low places in still air. 

The Discoverer has a turret system which enables it to maintain a position with 

the bow into wind/seas as needed, so wind direction for the most part will run 

from forward to aft. 

Therefore, the primary Safe Briefing Area will be forward of the moonpool. 

Personnel will report to the closest Safe Briefing Area. Personnel forward of 

the moonpool will report to the forward Safe Briefing Area and personnel aft of 

the moonpool will report to the aft Safe Briefing Area. Should an evacuation 

become necessary, procedures for evacuation are outlined in Section IX, H2S 

Emergency Procedures. 

L. Welding Prohibition 

There should be no welding, if H2S is detected at the surface, until the 

surrounding air is thoroughly tested with combustible gas and handheld H2S 

meter(s). 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 25 May 2011 

VIII. OPERATING CONDITIONS-Classifications 

A. Possible Hazardous Conditions (H2S Not Present) 

1. Warning Signs: None 

2. Alarm: None 

3. Characterized By: Routine drilling operations under control in zones that 

are classified as “H2S present” or ”H2S unknown”. This condition will be in 

effect continuously from the base of the structural casing (as described in 

the APD) to total depth unless it is necessary to go to a Condition I, II, or 

III. 

4. General Action: 

a. HSE Technicians and H2S technicians monitor H2S concentrations 

using the fixed gas detection system 

b. Be alert for a condition change 

c. Keep all safety equipment available and monitors functioning properly 

B. Condition I: Potential Danger (H2S Present ≥10 ppm but < 20 ppm) 

1. Warning Sign: 

“DANGER – POISONOUS GAS - HYDROGEN SULFIDE – DO NOT 

APPROACH IF RED LIGHTS ARE FLASHING” signs will be displayed on 

all sides of drillship (yellow with black lettering to be illuminated at night) 

and under conditions of poor visibility. 

2. Alarms: 

 In work areas: BLUE FLASHING LIGHT. Alarm signals will continue as 

long as the H2S concentration is greater than 10 but less than 20 ppm or 

until deactivated by the H2S Safety Technician or the Shell Drilling 

Foreman. Announcement will be made on ship’s PA system advising all 

personnel of the situation. 

3. Characterized By: 

Drilling operations area under control. Poisonous gases may be present 

in concentrations at threshold levels and may or may be detectable by 

odor. This condition will be in effect continuously from the time the H2S 

concentration reaches 10 ppm unless it is necessary to go to Condition II 

or III. NOTE: It is unlikely that a continuous concentration of H2S during 

exploration drilling operations will be tolerated for an extended time 

periods. Shell will take remedial efforts to stop the influx of H2S, up to and 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 26 May 2011 

including well abandonment, if Condition I persists. Action to be taken 

under Condition I is contained under Section VII “H2S Emergency 

Procedures”. 

4. General Action: 

a. Be Alert for a condition change. 

b. Check safety equipment for proper functioning. Keep available for 

immediate use. 

c. Monitor H2S concentrations for general increases during drilling 

operations. 

d. Follow the instructions of the supervisor. 

C. Condition II: Moderate Danger to Life (H2S Present ≥20 ppm but < 50 ppm) 

1. Warning Sign: 

“DANGER – POISONOUS GAS - HYDROGEN SULFIDE – DO NOT 

APPROACH IF RED FLAG IS FLYING OR IF RED LIGHTS ARE 

FLASHING” signs will be in place on all sides of the drillship (Yellow with 

black lettering to be illuminated at night and under conditions of poor 

visibility.) Two foot by three foot red flags will also be displayed. 

2. Alarm: 

Continuous sounding of the H2S siren (yelping tone) and RED LIGHT 

flashing. All alarm signals will continue as long as the H2S concentration 

is present at 20 ppm or more or until deactivated by the H2S Safety 

Technician or the Shell Drilling Foreman. The Vessel Master will manually 

trip the ship’s gas alarm. Announcement will be made on ship’s PA system 

advising all personnel of the situation. 

3. Characterized By: 

Critical well operations are underway or well control problems. Toxic 

gases are present above threshold levels. This condition shall be in effect 

when the H2S concentration is present at 20 ppm but less than 50 ppm. 

4. General Action: 

At a concentration of 20 ppm (15 minute time-weighted average) the BOE 

and USCG will be notified. The Vessel Management Team (VMT) will 

standby in the Operations Center to assist in developing H2S control 

procedures. Personnel assigned to control the H2S source will don 

SCBAs or facemasks with a hoseline connection. All others will don 

SCBA then report to the Safe Briefing Area with immersion suit and 

personal flotation device. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 27 May 2011 

D. Condition III: Extreme Danger to Life (H2S Present ≥ 50ppm) 

1. Warning Sign: 

 “DANGER – POISONOUS GAS – HYDROGEN SULFIDE – DO NOT 

APPROACH IF RED LIGHTS ARE FLASHING” signs will be in place on 

all sides of drillship (Yellow with black lettering to be illuminated at night 

and under conditions of poor visibility). 

2. Alarm: 

Continuous sounding of the H2S alarm (Yelping Tone) with BLUE AND 

RED LIGHTS flashing. All alarm signals will continue as long as the H2S 

concentration is present at greater than 50 ppm, or until deactivated by the 

H2S safety technician or the Shell Drilling Foreman. The Vessel Master will 

manually trigger the ship’s gas alarm. Announcement will be made on 

ship’s PA system advising all personnel of the situation. 

3. Characterized By: 

Loss of well control or released H2S concentration is greater than 50 ppm. 

4. General Action: 

a. The evacuation vessel will be contacted for assistance with 

evacuation. 

b. The BOE and USCG will be notified. 

c. The Shell SIMOPS Coordinator will be notified (907-382-4130) 

d. The Incident Command Team (ICT) in Shell’s Anchorage Office will be 

notified. 

e. All non-essential personnel (or all personnel if the situation warrants) 

shall be evacuated. Radio and other available communications shall 

be used to alert all air and water craft in the immediate vicinity of the 

rig. The Shell Drilling Foreman will advise the Anchorage Incident 

Command Team of plans to evacuate the rig. 

f. Evacuation will be conducted by moving personnel from Discoverer 

to the standby evacuation vessel. 

g. All people not specifically assigned to correct or control the situation 

shall stay in the Designated Muster Area or Safe Briefing Area as 

instructed, until evacuated by a rescue vessel or escape capsule. A 

suggested list of essential personnel to be left aboard is listed in 

Section IX. The number of essential personnel may be increased at 

the request of the Vessel Master, Noble Drilling Superintendent or 

Shell Drilling Foreman, as necessary. 

h. If the alarm sounds and it has not been preceded by Condition II, the 

actions of Conditions II shall be taken. Circulation will be stopped and 

self-contained breathing apparatus and air line work units shall be 

donned by all working personnel. The Drilling Contractor Safety 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 28 May 2011 

Representative shall check all personnel by roster. Vessels will be 

notified. The rig and shore dispatchers will also be notified of the 

condition and will continuously monitor the radio. 

i. If the flare is ignited, the burning or hydrogen sulfide will be converted 

to sulfur dioxide which is also poisonous. DO NOT ASSUME THAT 

THE AREA IS SAFE AFTER THE GAS IS IGNITED. CONTINUE TO 

OBSERVE EMERGENCY PROCEDURES. Follow the instructions of 

Supervisors. 

IX. H2S EMERGENCY PROCEDURES 

A. Condition I

If at any time 10 ppm or more (up to 20 ppm) of H2S is detected, the following 

steps will be taken: 

1. The person detecting the H2S must IMMEDIATELY notify the driller. The 

driller will, in turn, notify the Toolpusher and/or the Drilling Superintendent 

who will then notify the Shell Drilling Foreman and SIMOPS Coordinator. 

2. Central Control Room notifies ship of Condition I via the ships PA system. 

3. Orient the drillship relative to wind direction to minimize H2S exposure.

4. The H2S technician will establish communication with the control room, 

notifying the PIC of his intent to confirm H2S presence in the area of the 

alarm.

5. The H2S Technician and designated buddy shall put on their selfcontained breathing apparatus and take hand held detectors to the sensor 

area registering H2S, and verify the presence and source of the H2S. The 

buddy system will be used. 

6. The driller will shut down the mud pump, pick up to space out position and 

continue to rotate the drill pipe. 

7. The following personnel will immediately put on their breathing air units. 

a. All personnel on the rig floor. 

b. All personnel at the mud pits and shale shaker area. 

c. All personnel in the moon pool area. 

d. All personnel not in areas listed above will receive instruction via the 

PA, as to necessary response to the alarm. 

NOTE: At the discretion of the Vessel Master, Drilling 

Superintendent, and/or Shell Drilling Foreman, the H2S Safety 

Technician may give the OK to doff the SCBA should the 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 29 May 2011 

conditions warrant. SCBAs will be worn “at the ready” until an 

“all clear” is given. 

8. The Vessel Master, Noble Drilling Superintendent, or designee will 

alert all personnel in work areas that a Condition I exists. He shall 

be prepared to shut off the forced air circulation system and close 

all hatches downwind of, and below, the source of H2S. 

9. The Mud Engineer will run a Sulfide Determination on the flowline 

mud using a Garrett Gas Train provided by the mud supplier or 

catch a closed mud sample and pull a Sensidyne or similar 

ampoule to confirm the presence of H2S. The Mud Engineer will 

don proper PPE, to include SCBA, while retrieving a sample of 

flow line mud to perform the test. 

10. The Shell Drilling Foreman and Toolpusher will prepare plans to 

suppress the H2S as quickly as possible. Drilling operations must 

not proceed until the source of the H2S is determined and the well 

is circulated. Rig floor mud pit and shale shaker personnel will 

keep breathing air equipment on while monitoring this circulation. 

11. The Vessel Master, Noble Drilling Superintendent or designee will 

make sure all non-essential personnel are out of the potential 

danger area (mud pit area, mud storage room, store room, etc.). All 

personnel who remain in the potential danger area must use the 

“Buddy System”. 

12. The Shell Drilling Foreman shall notify the Shell Drilling 

Superintendent of current conditions and action taken who will then 

notify the Shell SIMOPS Coordinator. 

13. The H2S Safety Technician will see that all monitoring devices are 

functioning properly and reading accurately and will increase gas 

monitoring activities with portable units. 

14. The Shell Drilling Foreman or Noble Drilling Superintendent, shall 

direct the drillship dispatcher, or the local Call and Communication 

Center onshore to notify all boats in the area to go upwind, to stay 

on power and to maintain a continuous radio and visual watch. 

15. The Shell Drilling Foreman or Noble Drilling Superintendent shall 

direct the drillship dispatcher and the Shell SIMOPS Coordinator 

,the local Aviation Logistics Base onshore to notify aircraft enroute 

to the drillship of current conditions and the action to be taken. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 30 May 2011 

16. “DANGER – POISONOUS GAS - HYDROGEN SULFIDE – DO 

NOT APPROACH IF RED LIGHTS ARE FLASHING” warning signs 

must be posted on all sides of the drilling rig. 

17. The Shell Drilling Foreman, Vessel Master or Noble Drilling 

Superintendent will alert the dispatcher to assure continuous radio 

and phone watch. 

B. Condition II and III

If the H2S Concentration reaches 20 ppm, and the well is NOT attempting 

to flow, the following steps will be taken in addition to those steps listed 

above for Condition I. 

1. The person detecting the H2S must IMMEDIATELY notify the driller. 

He must then notify Vessel master, Noble Drilling Superintendent 

and the Shell Drilling Foreman who will then notify the Shell 

SIMOPS Coordinator. 

2. Automatic audible and visual alarms in the listed areas of the 

drillship.

3. The Central Control Room activates ship-wide gas alarm system 

and announces change of condition.

4. The ship’s crew will orient drillship relative to wind direction to 

minimize H2S exposure.

5. The driller will shut down the mud pump, pick up to space out 

position and continue to rotate the drill pipe. 

6. All personnel will receive instruction via the PA, as to necessary 

response to the alarm. 

7. Once breathing air equipment has been donned, the driller should: 

a. Stop pipe rotation 

b. Space out for well control 

c. Be ready to close the BOP’s 

d. Follow the “Well Control Procedure” in Section A-1 of the 

Appendix if well control problems develop. 

8. The Vessel Master, Shell Drilling Foreman, Noble Drilling 

Superintendent, or designee will alert all personnel in work areas 

that a Condition II or III exists. He shall be prepared to shut off the 

forced air circulation system and to close all hatches downwind of, 

and below, the source of H2S. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 31 May 2011 

9. All personnel outside of the living quarters and not listed above, 

must get their Type I Life Jacket and assigned SCBA, and report to 

the designated muster area for further instructions. If both the 

assigned SCBA and the safe briefing area are upwind of the 

wellbore, the SCBA may be carried to the designated muster area; 

however, if there is any doubt, the SCBA should be donned and 

activated immediately. If it becomes necessary to go 

through/across the moon pool area, rig floor or mud circulating area 

to get to the designated muster area, the nearest breathing air 

equipment available is to be donned. Under a Condition II 

situation, those personnel inside the living quarters will secure their 

SCBA and Type I life jackets and proceed to the designated muster 

area. Under a Condition III, all personnel inside the living quarters 

will go to the designated muster area with air equipment on and 

then proceed to the appropriate safe briefing area, as directed by 

the Person In Charge (PIC). Once at the safe briefing area, 

personnel should plug-in, close SCBA cylinder valves, and use the 

Cascade System. An effort should be made to conserve air still 

stored in the SCBA cylinder. 

10. Persons should always put on breathing air equipment before 

assisting someone affected by H2S gas, and use the “buddy 

system”. If the affected person is stricken in a high concentration 

area, a safety belt with 50’ of tail line should be worn by the rescuer 

who should obtain standby assistance before entering the area. 

The “buddy system” must always be used when entering possibly 

contaminated areas. 

11. The Shell Drilling Foreman, Vessel Master or Noble Drilling 

Superintendent shall direct the drillship dispatcher, and the Shell 

SIMOPS Coordinator to notify all boats in the area to go upwind to 

stay on power and to maintain a continuous radio and visual 

watch. 

12. The Shell Drilling Foreman, Vessel Master or Noble Drilling 

Superintendent shall direct the rig dispatcher, and the Shell 

SIMOPS Coordinator to notify aircraft enroute to the drillship of 

current conditions and the action to be taken. 

13. The “DANGER – POISONOUS GAS - HYDROGEN SULFIDE – DO 

NOT APPROACH IF RED LIGHTS ARE FLASHING” signs on all 

sides of the drillship are to be displayed. 

14. The Shell Drilling Foreman, Vessel Master or Noble Drilling 

Superintendent will alert the radio operator to establish a 24-hour 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 32 May 2011 

radio and phone watch. The radio operator shall alert vessels and 

the Shell SIMOPS Coordinator to standby for possible evacuation. 

15. Evacuate non-essential personnel when H2S reaches a 

concentration exceeding 50 ppm in the air. A personnel basket will 

be used to evacuate to the evacuation vessel(s). All personnel will 

stay in their SCBAs until the vessel is moved upwind away from the 

drillship and the all clear is sounded. Personnel will “plug-in” to the 

Breathing Air Cascade system on the evacuation vessel, closing 

the SCBA valves and using the supplied air via the Breathing Air 

Cascade system to conserve stored air in the SCBA. Life boats 

(capsules) will be used if the evacuation vessel is not readily 

available or if conditions require. 

13. The Shell Drilling Foreman will assess the situation and assign 

duties to each person needed to bring the situation under control. 

When the severity of the situation has been determined, all persons 

will be advised. The Shell Drilling Foreman or his designated 

representative will: 

a. Continue to direct corrective action to bring the situation 

under control 

b. Notify the Shell Drilling Superintendent of the situation and 

results 

14. The Shell Drilling Superintendent will be responsible for notifying 

the following regulatory agencies: 

a. BOEMRE (Anchorage District) 

b. U.S. Coast Guard 

c. Alaska Department of Natural Resources 

d. All other required agency 

e. Shell SIMOPS Coordinator 

15. If an H2S concentration exceeding 50 ppm in the air is recorded at 

the outer perimeter of the drillship, all known air and water craft in 

the immediate vicinity of the drillship location will be notified by 

marine radio and directed to move upwind immediately. 

C. Evacuation Procedures 

1. An order to evacuate the vessel will be given by the Vessel Master.

2. Evacuation will be conducted via personnel basket transfer from the 

Discoverer to the evacuation vessel (to be determined). 

3. Personnel will open their SCBA cylinder valve and disconnect from 

the Discoverer’s cascade manifolds immediately prior to boarding 

the personnel basket for transfer. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 33 May 2011 

4. Upon transfer to the evacuation vessel each person will be directed 

to the H2S muster area and connect their SCBA to the breathing air 

manifolds, then close their SCBA cylinder.

X. SPECIAL OPERATIONS 

A. Other Operations 

1. Logging Operations: Drilling fluid should be treated with H2S scavanger 

prior to logging to minimize the corrosive/embrittling effects of H2S on 

the wireline and logging tools. 

2. Stripping Operations: Personnel must monitor displaced drilling fluid 

returns and wear protective breathing equipment in the working area 

when the atmospheric concentration of H2S reaches 20 ppm or if the 

well is under pressure. 

3. Gas-cut drilling fluid or a well kick from H2S-bearing zone: When, and 

if, a decision is made to circulate out a kick, personnel in the working 

area during bottoms-up and extended-kill operations must wear 

protective breathing equipment 

B. Monitor Observation During Specific Operations 

During drilling operations the H2S levels indicated by the monitors must be 

continuously observed during the following operations after penetrating a 

zone where H2S was identified during drilling: 

1. When pulling a wet string of drillpipe 

2. When circulating bottoms-up after a drilling break 

3. During cementing operations (including abandonment) 

4. During logging operations 

5. When circulating to condition drilling fluid 

XI. WELL CONTROL 

The following well control practices should be initiated: 

 

A. Trip Gas 

If high trip gas or high connection gas concentrations are encountered, the 

degasser should be used and the gas separated and burned if that is the 

best course of action. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 34 May 2011 

B. All Kicks 

Assume any influx of formation fluid into the wellbore contains H2S. When 

the decision is made to circulate out the influx, all personnel involved will 

don breathing air equipment from the time the influx reaches the BOP until 

it is determined whether H2S is present. The following steps should be 

taken when the influx occurs: 

1. Shut in the well using normal techniques. Record drill pipe pressure, 

casing pressure, and volume of influx. 

2. Notify The Shell Drilling Foreman, the Noble Drilling Superintendent 

and the Shell SIMOPS Coordinator. 

3. If directed to circulate out the influx, proceed as outlined in the “Well 

Control Procedure” in Section A-1 of the Appendix. 

If the mud has been contaminated with H2S, it may be necessary to treat it with 

zinc basic carbonate (or equivalent) to treat out the H2S. A “Mud Treating” 

procedure is given in Section A-3 of the Appendix. 

XII. LOST CIRCULATION 

If the lost circulation occurs, proceed as outlined in the “Lost Circulation 

Procedure” in Section A-2 of the Appendix. 

XIII. PARTIAL EVACUATION PROCEDURE 

In the event that it becomes necessary to evacuate the rig due to well control 

problems or fire, the Drillship Fire and Boat Station and Abandonment Procedure 

will be used. 

 For H2S evacuations, see Section B-6 of the Appendix. 

XIV. RESPONSIBILITIES AND DUTIES – H2S 

A. All Personnel 

1. It is the responsibility of all personnel on the drillship, as well as any 

other personnel assisting in the drilling or abandonment of the well, to 

familiarize themselves with the procedures outlined in the “H2S 

Contingency Plan”. 

2. Each individual is responsible for seeing that his assigned safety 

equipment is properly stored, easily accessible and routinely 

maintained. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 35 May 2011 

3. Each person must familiarize himself with the location of safety 

equipment aboard the drillship and be able to use all safety equipment 

at a moment’s notice. The location of all safety equipment is given in 

Section C-1 of the Appendix. 

4. All personnel must read the Contingency Plan and sign the 

“Contingency Plan Memorandum of Understanding”. 

5. Report any indications of H2S to those in the area first, then to 

VESSEL MASTER, Drilling Superintendent and/or to The Shell Drilling 

Foreman. 

B. Shell Drilling Foreman 

1. The Shell Drilling Foreman is responsible for thoroughly understanding 

and enforcing all aspects of the “H2S Contingency Plan”. 

2. The Shell Drilling Foreman is responsible for seeing that all safety and 

emergency procedures outlined in the “H2S Contingency Plan” are 

observed by all personnel participating in the drilling of the well. 

3. The Shell Drilling Foreman will advise The Shell Drilling 

Superintendent and the Shell SIMOPS Coordinator whenever the 

procedures, as specified herein, cannot be complied with. 

4. The Shell Drilling Foreman is responsible for equipment installation on 

the drillship prior to spudding a potential sour gas well as described 

under Section V “Safety Equipment”. 

5. The Shell Drilling Foreman in conjunction with the Noble Drilling 

Superintendent is responsible for scheduling training for all Shell, 

contractor and Noble personnel assigned to the drillship. 

6. If the presence of H2S is reported and confirmed, The Shell Drilling 

Foreman is responsible for immediately advising the Emergency 

Room, the Vessel Master, the SIMOPS Supervisor, and the Drilling 

Superintendent. 

7. The Shell Drilling Foreman shall restrict the number of personnel on 

the drillship to a minimum during expected hazardous operations. 

C. Vessel Master / Noble Drilling Superintendent 

1. The Vessel Master and/or Drilling Superintendent are responsible 

for thoroughly understanding the contents of the “H2S Contingency 

Plan”. In the absence or incapacitation of the Vessel Master, or 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 36 May 2011 

Noble Drilling Superintendent. The Toolpusher will assume 

responsibilities designated herein. 

2. It is the responsibility of the Vessel Master and/or Drilling 

Superintendent to see that all safety and emergency procedures 

outlined in the “H2S Contingency Plan” are observed by all Noble 

drilling and marine personnel aboard the rig. 

3. The Drilling Superintendent shares the responsibility with the Shell 

Drilling Foreman in scheduling training for personnel assigned to 

the drillship. 

4. The Vessel Master and/or Noble Drilling Superintendent will be 

responsible for directing the shutting off the forced air circulating 

system and closing all hatches in the event that H2S is detected in 

the atmosphere at any time. 

5. The Vessel Master and/or Noble Drilling Superintendent will be 

responsible for inspecting the drillship to make sure that all 

passageways remain unobstructed. 

6. The Vessel master and/or Noble Drilling Superintendent is 

responsible for alerting all personnel during a Condition I, II, or III 

alert and for displaying warning signs and flags (if used) as outlined 

under Section VII “Operating Conditions – Classification”. 

7. The Vessel Master is responsible for choosing the drillship heading 

to provide the highest level of protection for all personnel in the 

event H2S is detected. 

D. H2S Safety Technicians 

 

1. There will be at least two (2) H2S Safety Technicians aboard the 

vessel at all times during compliance operations. One H2S Safety 

Technician will work the day shift and the other will work the night 

shift. Both will respond to drills or H2S release at any time. 

2. Is responsible for performing a weekly inventory to assure that all 

safety equipment is being properly stored and maintained. 

3. Is responsible for logging the arrival and departure of all personnel 

on the drillship, as per BOE requirement. 

4. Is responsible for the H2S training, which includes the use, 

maintenance, and storage of the safety equipment. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 37 May 2011 

5. Is responsible for issuing H2S safety equipment to arriving 

personnel on the rig and for collection of same for departing 

personnel. 

6. Is responsible for the maintenance and repairs of all H2S safety 

equipment. 

7. Is responsible for the required inspection and sanitizing of the H2S 

safety equipment. 

8. Is responsible for the maintenance of H2S Safety Training Class 

Attendance Records, and other record keeping required. He shall 

furnish the Shell Drilling Foreman a copy of all class attendance 

records. 

9. Will observe and assist during weekly H2S drills. 

10. Will test the H2S sensors daily for response. A copy of the results 

will be given to The Shell Drilling Foreman. 

11. Will calibrate the H2S sensors weekly. A copy of the results will be 

given to The Shell Drilling Foreman. 

E. Dispatcher/ Radio Operator 

 

1. The Dispatcher is responsible for notifying all personnel in the area 

of the rig (including any workboats and/or helicopters) of a change 

in conditions. The Shell SIMOPS Coordinator shall also be notified. 

F. Noble Toolpusher/ Driller 

1. The Toolpusher and Driller must be completely familiar with the 

steps each must take during a Condition I, II, or III Emergency as 

outlined under Section VIII “H2S Emergency Procedure”. 

2. The Toolpusher and Driller must be completely familiar with their 

assigned duties during well control and lost circulation problems as 

outlined under Section XI “Well Control” and Section XII “Lost 

Circulation”. 

3. In the absence or incapacitation of all Shell Drilling Foremen, the 

Vessel Master and Noble Drilling Superintendent then the 

Toolpusher will assume the lead role in H2S response as 

designated herein. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 38 May 2011 

G. Mudlogger 

1. Is responsible for the switch inside the mudlogging unit that controls 

the forced air duct leading to the unit. 

2. Is responsible for a multi-gas detector which will be kept in the 

mudlogging unit. 

H. Mud Engineer 

1. Must have a Garret Gas Train Kit for measuring the sulfides in the 

mud if a water-based drilling fluid is used, and must be fully trained 

on its use. 

2. Must be familiar with the “Mud Treating” procedure for H2S cut mud 

in Section A-3 of the Appendix. 

3. Is responsible for assuring that the rig has a sufficient supply of 

100% zinc carbonate or an equivalent H2S scavenger. 

I. H2S Flaring 

1. When flaring, hourly readings for SO2 and H2S will be monitored 

with a fixed or portable instrument implementing the buddy system. 

2. Detection of 5 ppm of SO2: Personal protective measures will be 

taken by personnel in work areas affected. Self contained 

breathing apparatus will be utilized to take hourly readings using 

the buddy system. All unnecessary personnel will be evacuated 

from the affected area and if necessary from the facility using only 

designated personnel to take corrective action. The designated 

personnel will be the same as listed for an H2S emergency 

response. Briefing areas will be utilized as necessary. H2S 

readings will be monitored and logged along with SO2 readings. 

3. Detection of 2 ppm of SO2: Personal protective measures will be 

taken by personnel in work areas. Self contained breathing 

apparatus will be utilized to take hourly readings using the buddy 

system. All unnecessary personnel will remain out of the affected 

area upwind. Quarters or briefing areas will be utilized as needed 

pertaining to emergency conditions as described in this plan for H2S 

and the concentration of SO2. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 39 May 2011 

XV. PROCEDURE FOR INFORMING PERSONNEL OF H2S CONTINGENCY PLAN 

A. Aboard Drillship 

1. There will be a complete copy of this H2S Contingency Plan 

available in the Shell Drilling Foreman’s office, Vessel Master’s

office, Emergency Room, Radio Room and the Noble Drilling 

Superintendent’s office. 

2. ALL Personnel arriving at the rig will report immediately to the H2S 

Safety Technician for familiarization with the Contingency Plan. 

Each person will be required to sign a log indicating that they have 

been briefed on, and do understand, this H2S Contingency Plan. 

3. The H2S Safety Technician will train the crews and familiarize them 

with the “Contingency Plan Memorandum of Understanding”. 

Written records will be maintained. 

B. Aboard Support Vessels 

A copy of this H2S Contingency Plan will be given to the Master of each of 

the support vessels. They will be required to sign a log indicating that they 

have read and understand the plan. 

XVI. SEARCH & RESCUE TEAMS 

A. Primary Goal 

Rescue team members must realize that the primary goal of the team 

should be to inspect all areas of the drillship for personnel who have been 

overcome by H2S or SO2. However, from a practical stand point, the 

potential for someone to be overcome is greatest during a Condition III 

release as indicated by the Flashing BLUE & RED lights and siren, it is 

essential that the Rescue Teams report to the staging area & report in with 

their assigned SCBA units and then immediately begin a search of the 

below deck areas. 

B. Critical Areas 

During drilling or P&A activities, the four most critical areas can be defined 

as the shale shaker area, mud pit area, possum belly and drill floor area. 

The trip tank area is also critical when tripping pipe. Accordingly, the H2S 

Emergency Station Bill is designed to ensure that such areas are quickly 

evaluated after and/or during any significant H2S release. For example, 

the H2S Technicians during such times ensure that the shaker area and 

trip tank will be checked, while the Toolpusher and Noble Drilling 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 40 May 2011 

Superintendent ensure the drill floor is checked. In addition, the Rescue 

Team ensures that all below deck water-tight doors will be secured to 

prevent migration of gas. 

C. Unconscious Victims 

Rescue Team members must realize that in the event an unconscious 

victim is found, it may or may not be necessary to move the victim before 

administering the necessary first-aid. The determining factor will be the 

presence of H2S or some other threat which poses an immediate danger 

to victim as well as the rescue personnel. Since procedures call for the 

mud pumps to be shut down if H2S is detected, it is unlikely that large 

volumes of H2S will continue to be released. 

D. Purging the Area 

This coupled with the ventilation systems presently on the drillship, 

enhance the possibility that any H2S or other gas will be quickly purged 

from an area, such as the pit area. Persons found unconscious may have 

tripped or fallen when responding to the H2S alarms, and as a result may 

have suffered neck or spinal injuries. In such a case, moving the victim 

could prove fatal. Therefore, it is essential that the Rescue Team properly 

determine not only the victim condition, but also the condition of the 

surrounding area. 

E. Procedures and Drills 

1. CONDITION I 

a. ON-DUTY TEAMS: IN THE EVENT OF CONDITION I OR II 

1) Proceed to staging area and report in, then don 30 minute 

SCBA. Do not open cylinder valve or don facepiece. 

2) Check portable H2S detectors and Clear-Com Devices 

2. CONDITION II or III 

a. ON-DUTY TEAMS: IN EVENT OF AN H2S RELEASE 

1) Proceed to staging area and report in, then don assigned 

RESCUE TEAM SCBA. 

a. Check portable H2S detectors and Clear-Com devices. 

b. In the event a team member(s) is missing, proceed as a 

group of 3 or 2. Do not proceed alone. 

2) Proceed in teams down to designated start point. 

a. Secure watertight doors and hatches along way to 

prevent migration of H2S. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 41 May 2011 

3) Team 1 – Follow normal rescue team procedures as outlined 

in the Station Bill. 

Team 2 – Follow normal rescue team procedures as outlined 

in the Station Bill. 

a. Continue to secure all watertight doors and hatches to 

prevent gas migration. 

4) In the event you encounter a person(s) in distress: 

a. One team member checks to see if victim is breathing 

while other team member checks for H2S in area. 

 If victim is breathing and no contamination is 

present, alert the Medical staff in the infirmary. 

Continue to monitor area with H2

S Detectors. 

 If victim is breathing and/or contamination is 

present, remove victim to safe area immediately 

and then notify the Medical staff. 

b. Verify area is safe from H2S with portable detector, 

before removing mask. 

c. Check victim again for breathing and pulse (heartbeat). 

d. Administer mouth-to-mouth resuscitation if victim is not 

breathing or CPR if victim has no heart beat. 

e. Alert the Medical staff immediately. Do not leave anyone 

in distress unattended. 

f. Obtain oxygen resuscitator and stretcher. Typically, this 

equipment will be brought to scene by Medical staff.. 

 Replace mouth-to-mouth activities with the 

mechanical resuscitator. 

 Transfer patient(s) to Safe Briefing Area or 

Infirmary as quickly as possible for further 

treatment. 

NOTE: When transferring a patient, every effort must be made to 

use a route that has been verified to be gas free. If a 

breathing patient must be transferred through an area 

that could potentially be contaminated, it will be 

necessary to supply a safe source of breathing air to the 

patient. 

5) Rescue Teams should meet in the Staging Area or 

designated Safe Briefing Area after completing their 

respective search activities. 

a. If only one team has conducted the search, then proceed 

from the staging to the Designated Safe Briefing Area. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 42 May 2011 

b. Report to supervisory personnel and be prepared to 

conduct additional search, rescue and/or hazard 

assessment activities as needed. 

c. Check SCBA cylinder to ensure it contains a minimum of 

1500 psi; recharge or replace the cylinder if necessary. 

a. OFF-DUTY RESCUE TEAM: IN THE EVENT OF AN H2S 

RELEASE 

1) Be prepared to assist as needed. 

 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 43 May 2011 

APPENDIX 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 44 May 2011 

APPENDIX – SECTION A 

PROCEDURES 

SECTION A-1 

WELL CONTROL PROCEDURES 

All efforts should be made to prevent a well kick, which may result from gas cut mud, 

abnormal pressure, and loss in circulation, or swabbing. Should any of the following 

conditions occur, the well should be checked for flow. 

1. Increase in flow across the shale shaker. 

2. Gain in pit volume. 

3. Hole does not take correct fill on trips. 

4. Significant drilling break. 

5. Decrease in pump pressure. 

6. Significant increase in connection gas. 

If well flow is confirmed, the following actions will be taken: 

Shut-In Procedure While Drilling 

1. Sound kick alarm 

2. Pick up to space out position and break off top drive or false kelly 

3. Install stab-in safety valve (TIW Valve) in top of drill string and close 

4. Close BOP and make certain well is shut-in 

5. Re-install top drive or false kelly and open TIW valve 

6. Read and record: 

a. Shut-in drillpipe pressure, if any 

b. Shut-in casing pressure 

c. Mud volume gained. 

Shut-in Procedure While Tripping or Running Casing 

1. Sound kick alarm 

2. Pick up to space out position 

3. Install crossover and TIW valve in top of drill string or casing and close 

4. Close BOP and check to see that well is shut-in 

5. Make up top drive or false kelly onto drill string or casing and open TIW valve 

6. Read and Record: 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 45 May 2011 

a. Shut-in drillpipe or casing pressure, if any 

b. Shut-in annulus pressure 

c. Mud volume gained. 

Shut-in Procedure With Pipe out of the Hole 

1. Close well in with blind/shear rams and check to see that it is shut-in 

2. Close hydraulic choke and open choke line 

3. Read and record: 

a. Shut-in well pressure 

b. Mud volume gained 

The handling of the H2S kick will normally involve one of the two following techniques: 

 Pumping the kick away 

 Circulating the kick out 

The technique selected must be based on the conditions existing at the time of the 

occurrence. The selected technique will have as its objective the protection of human 

life, protection of the environment, and protection of property respectively. 

As long as it is operationally feasible and safe to do so, all kicks (especially H2S kicks) 

will preferentially be bullheaded away rather than circulated out. This plan of action has 

the advantage of minimizing the surface risk to personnel, environment, and service 

equipment. 

In some cases, it will be necessary to set a barite or cement plug over the H2S-bearing 

formation to accomplish proper well control. If drilling cannot safely proceed the well 

may be permanently abandoned. 

If the decision is made to circulate out the H2S kick, operations should not be initiated 

until briefings have been held with all personnel involved, equipment is made ready and 

alert/warning signs are displayed. 

Regardless of which technique is employed to deal with an H2S kick, all personnel on 

the rig floor and mud circulating areas should secure SCBAs and ensure that they are 

“at ready” should donning become necessary. 

 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 46 May 2011 

SECTION A-2 

LOST CIRCULATION PROCEDURE 

If lost circulation is experienced during any phase of the drilling operations, every effort 

will be made to fill the hole and keep it full. The driller should: 

1. Pick up to space out position and shut down the mud pumps 

2. Notify the Toolpusher and Shell Drilling Foreman as soon as practical 

3. Fill trip tank with fluid (seawater, drilling water or drilling fluid may be used). 

Consideration should be given to keeping one side of the trip tank filled with a 

lower weight fluid during drilling operations 

4. Begin filling hole from the trip tank. If hole will not fill from the trip tank, begin 

pumping fluid into the annulus keeping track of all fluid volumes pumped 

NOTE: Pumping excessive volumes of light weight fluid has the risk of reducing 

hydrostatic pressure in the wellbore and inducing the well to flow. 

5. Work the drill string while attempting to fill and regain circulation to avoid 

differential sticking 

6. When hole fills, determine and record the volume of water required to fill the 

hole. 

a. Check well for flow. If well is static and hole stands full, monitor for 

possible flow. Keep trip tank on the hole. 

b. If well is flowing, shut well in per “Well Control Procedure” 

7. Procedure(s) to regain circulation will be developed based on hole conditions. 

DO NOT PULL INTO CASING until approved by the Shell Drilling Foreman. 

One or more of the following methods will be used: 

a. Introducing lost circulation materials into the mud system and/or 

minimizing mud weight 

b. Spotting lost circulation pills over the suspected thief zone 

c. Bullheading cement or other sealing fluid into the thief zone 

d. Pulling up into the casing to allow the hole to heal 

e. If the loss circulation problem is severe, consideration will be given to 

setting an additional casing string through the thief zone and cementing it 

in place 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 47 May 2011 

SECTION A-3 

MUD TREATING 

1. Zinc oxide, or an equivalent H2S scavenger, will be used to treat out H2

S in the 

mud system. It should not be added to the system until soluble sulfides are 

detected in the mud by the Mud Engineer and approval is given by the Shell 

Drilling Foreman 

2. After H2S is detected, the initial treatment of the H2S scavenger should be 

sufficient to treat the soluble sulfides only to a zero concentration. Treatment in 

excess is to be avoided. 

3. The mud system must be maintained with a pH greater than 10.0. The pH of the 

mud system will be maintained by adding lime or caustic soda or equivalent and 

the high pH should be maintained below compliance depth. A rapid decrease in 

pH is a possible indication of the presence of H2S in the mud system. 

4. The mud system could contain H2S and/or sulfides if agitation is not adequate to 

remove all of it. 

5. The Mud Engineer will have a Garrett-Gas-Train test kit aboard the vessel readily 

available to conduct a test for soluble sulfides that will confirm the presence and 

approximate amount of H2S in the mud. 

6. From compliance depth to total depth, the Mud Engineer will test for sulfides at 

least every 12 hours using Garrett-Gas-Train test kit. Detailed instruction for 

performing these tests will be maintained on the rig (API RP 13B). 

7. The results of these checks or any other indication of H2S in the mud system will 

be included as a routine part of the mud engineer’s daily reports. 

8. Pilot tests on mud samples will be performed to determine, in advance, the 

effects of 1⁄2 and 1 lb/bbl concentrations of the H2S scavenger on the rheological 

properties of the mud system. 

Mud Treatment Plan 

Specific to an H2S Occurrence 

Pre-Planning 

1. At least one complete Garrett Gas Train and required supplies must be available 

on the drillship before drilling commences on any Chukchi Sea exploration well. 

Because of the distance from sources of supply and logistical considerations, two 

complete Garrett Gas Trains should be available on the rig. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 48 May 2011 

2. A baseline sulfide level in the circulating system will be established well in 

advance to entering potential H2S zone. 

3. Adequate scavengers (zinc oxide or equivalent) will be on board prior to entering 

potential H2S zone. Enough zinc oxide or other scavenger will be on board to 

add twice the amount necessary to remove all H2S to the entire circulating 

system (e.g., two complete treatments of zinc carbonate at 2 ppb). 

4. The PSM (POM) in the circulating system should be ≥ 5 mL prior to entering 

potential H2S zone. 

5. The electrical stability will be increased to as high as practical prior to entering 

potential H2S zone (>500 mV ES is sufficient). 

Treatments and Procedures 

1. Maintain PSM in the suction ≥ 5 mL. 

2. If the PSM at the flow line is depleted to <3 mL, the suction PSM should be 

increased to commensurate with the depletion rate. 

3. Zinc oxide should not be added to the system unless soluble sulfides (greater 

than the established base line) are detected in the mud system by the Mud 

Engineer and approval is given by the Shell Drilling Foreman. 

4. If an H2S increase is seen to 200 mg/L above the baseline through the Garret 

Gas Train, 1⁄4 ppb zinc oxide should be added to the mud system. 

5. If an increase of 200 mg/l to 400 mg/l above the baseline is observed, 1⁄2 ppb zinc 

oxide should be added to the system. 

6. If an increase of 400 mg/l to 600 mg/l is noticed, 3⁄4 ppb zinc oxide should be 

added. 

7. If an increase of 600 mg/l to 800 mg/l is noticed 1 ppb zinc oxide should be 

added. 

8. These treatments are based on the assumption that 1 ppb zinc oxide will treat 

out 800 mg/l to 1,200 mg/l H2S in the drilling fluid. . 

9. The objective will be to maintain the sulfide level at the baseline. Anything above 

the baseline will have the potential for embrittlement and/or corrosion of the drill 

string and other critical rig components to occur. 

10. The Garret Gas Train test will be run a minimum of once every 12 hrs. (or as hole 

conditions dictate). It is very important to adjust the baseline to set a target for 

follow-up treatment it in the event that H2S is encountered as drilling progresses. 

11. Pilot testing with zinc oxide should be done to ensure that effective treatments 

are being made to the system to minimize any H2S picked up while drilling. 

12. In the event of a temporary abandonment or suspension 2 ppb zinc oxide will be 

added to the drilling fluid left in the hole. 

Note: The objective is to treat all active sulfides in the mud system with zinc oxide to 

form ZnS (zinc sulfide) which is a very stable compound in a reaction that is 

essentially non-reversible. However, caution should be exercised to match 

treatments to active sulfides above the baseline so as to minimize potential toxic 

impacts. 
Hydrogen Sulfide Contingency Plan 

Shell Gulf of Mexico Inc. 49 

Zinc Oxide Treatment

0

500

100015002000250030003500

0.250.50.75 11.251.51.75 22.252.52.75 33.253.5

Zinc Oxide (ppb)

Soluble Sulfides Above 

Baseline (mg/l)
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 50 May 2011 

APPENDIX-SECTION B 

GENERAL INFORMATION

SECTION B-1 

TOXICITY OF VARIOUS GASES 

Common Name 

Chemical 

Formula 

Specific 

Gravity1 PEL (OSHA)2 STEL3

Lethal4

Limit, ppm

Hydrogen Cyanide HCN 0.94 10 150 300 

Hydrogen Sulfide H2S 1.18 10 15 600 

Sulfur Dioxide SO2 2.21 2 5 1000 

Chlorine Cl2 2.45 1 

Carbon Monoxide CO 0.97 35 200/1 hour 1000 

Carbon Dioxide CO2 1.52 5000 5% 10% 

Methane CH4 0.55 90000 

(9%) 

Combustible 

(Above 5 % in air) 

1 Air=1.0 

2

 Permissible - Concentration at which is believed that all workers may repeatedly 

be exposed, day after day, without adverse effect. 

3

 STEL - Short Term Exposure Limit. 

4

 Lethal - Concentration that will cause death with short-term exposure. 

PROPERTIES OF GASES 

A. CARBON DIOXIDE 

1. Carbon Dioxide is usually considered chemically inert although it is both a 

suffocant and toxic to humans in high concentrations. It is 1.52 times 

heavier than air and will concentrate in low areas of still air. Humans 

cannot breathe air containing more than 10% CO2 without losing 

consciousness. Air containing 5% CO2 will cause disorientation in a few 

minutes. Continued exposure to CO2 after being affected will cause 

convulsions, coma, and respiratory failure. 

2. The PEL-TWA8 of CO2 is 5000 ppm. STEL (15 min) to CO2 is 50,000 ppm 

(5%). 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 51 May 2011 

3. This gas is colorless, odorless, and can be tolerated for short time periods 

in relatively high concentrations. In higher concentrations, short term 

exposure can result in suffocation due to displacement of oxygen from the 

environment. Continued exposure can result in a blood pH drop with 

subsequent toxic impacts. 

B. HYDROGEN SULFIDE 

1. Hydrogen Sulfide (H2S) is a colorless, transparent, flammable gas. It is 

heavier than air and, hence, may accumulate in low places. 

2. Although the slightest presence of H2S in the air is normally detectable by 

it characteristic “rotten egg” odor, it is dangerous to rely on the odor as a 

means of detecting excessive concentrations because the sense of smell 

is rapidly lost, allowing lethal concentrations to be accumulated without 

warning. The following table indicates the poisonous nature of H2S. 

CONCENTRATION in AIR 

EFFECTS 

% H2S ppm gr/100 

SCF1

0.001 10 0.65 Safe for 8 hours without respirator. Obvious and unpleasant 

odor. 

0.0015 15 0.975 Safe for 15 minutes of exposure without respirator. 

0.01 100 6.48 Kills smell in 3-15 minutes; may sting eyes and throat IDLH 

0.02 200 12.96 Kills smell quickly; stings eyes and throat. 

0.05 500 32.96 Dizziness; breathing ceases in a few minutes; need prompt 

artificial respiration. 

0.07 700 45.92 Rapid Unconsciousness; death will result if not rescued 

promptly. 

0.1 1000 64.80 Instant unconsciousness, followed by death within minutes. 

 1 Grains per 100 Standard Cubic Feet 

Treatment Procedures for Hydrogen Sulfide Poisoning 

A. Remove the victim to fresh air. 

B. If breathing has ceased or is labored, begin resuscitation immediately. 

NOTE: This is the quickest and preferred method of clearing victim’s lungs 

of contaminated air; however, under disaster conditions, it may not be 

practical to move the victim to fresh air. In such instances, where those 

rendering first aid must continue to wear masks, a resuscitator should be 

used. 

C. Apply oxygen resuscitator to help purge H2S from the blood stream. 

D. Keep the victim at rest and prevent chilling. 

E. Get victim under physician’s care as soon as possible. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 52 May 2011 

C. SULFUR DIOXIDE 

1. Sulfur Dioxide (SO2) is a colorless, non-flammable, transparent gas. 

2. SO2 is commonly produced during the burning of H2S. Although SO2 is 

heavier than air, it can be picked up by a breeze and carried downwind at 

elevated temperatures. Since SO2 is extremely irritating to the eyes and 

mucous membranes of the upper respiratory tract, it has exceptionally 

good warning powers in this respect. The following table indicates the 

toxic nature of SO2. 

SO2 Effects 

CONCENTRATION in AIR 

% SO2 PPM EFFECTS 

0.003 – 

0.005 

3 to 5 Pungent odor, normally a person can detect SO2in this 

range. 

0.012 12 Throat irritation, coughing, constriction of the chest, tearing 

and smarting of eyes. 

0.15 150 So irritating that it can only be endured for a few minutes. 

0.05 500 Causes a sense of suffocation, event with the first breath. 

0.10 1000 Death may result unless rescued promptly. 

3. If gas containing H2S is burned, the following steps must be taken to 

protect against SO2. 

a. Monitor the SO2 concentration in the air with portable or strategically 

placed fixed devices capable of detecting a minimum of 2 ppm or SO2; 

b. Take readings at least hourly and at any time personnel detect SO2

odor or nasal irritation; 

c. Implement the personnel protective measures specified in the H2S 

Contingency Plan if the SO2 concentration in the work area reaches 2 

ppm; and 

d. Calibrate devices every 3 months if you use fixed or portable electronic 

sensing devices to detect SO2. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 53 May 2011 

SECTION B-1 

H2S CONTINGENCY PLAN MEMORANDUM OF UNDERSTANDING 

Signature Form: 

Company: ______________________________ 

Well: __________________________________ 

I, ________________________, an employee of ________________________, have 

been briefed on the H2S contingency plan and understand it. 

________________________________________

 _____________________________ 

Signature Date 

NOTE: This signed form will be kept on file on the drillship. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 54 May 2011 

SECTION B-2 

BREATHING AIR EQUIPMENT DRILLS FOR 

ON-DUTY PERSONNEL 

On-duty personnel include Drilling, Marine and Roustabout Crew, Vessel Master, Noble 

Drilling Superintendent, H2S Safety Technician, the Shell Drilling Foreman and all other 

personnel on tour including contractors and catering personnel.. 

The Mudlogger and Mud Engineer will report to the Muster Area, and then take 

directions from the PIC. 

An H2S drill and training session will be conducted weekly. 

The purpose of this drill is to instruct the crews in the operation and use of breathing air 

and H2S related emergency equipment and to allow the personnel to become 

acquainted with using the equipment under working conditions. The crews should be 

trained to put on the breathing air equipment within one minute after an H2S emergency 

has been alerted. 

The following procedure should be used for weekly drills. The Shell Drilling Foreman, 

VESSEL MASTER, and Drilling Superintendent must be satisfied that the crews are 

proficient with the equipment. 

NOTE: The drill will be conducted as outlined under “Emergency Procedures for 

Condition II and Condition III” 

1. All on-duty personnel should be informed that a drill will be held. 

2. The H2S Safety Technician should initiate the drill by signaling as he would if he 

detected H2S. 

3. The driller should shut down the mud pumps, pick up to space out position and 

continue to rotate the drillpipe while he and the drilling crew don their breathing 

air equipment. The Mudlogger, Mud Engineer, Toolpusher, Noble Drilling 

Superintendent, and affected Shell personnel should also don their breathing air 

equipment. 

4. The driller will proceed as if the well is flowing; simulate closing the well in, but 

DO NOT ACTUALLY CLOSE THE BOP without orders from the Toolpusher. 

5. After reporting to the Muster station, The Mud Engineer will be directed to 

perform a flowline check for mud weight and funnel viscosity, and catch a mud 

sample for the sulfides test on the mud. This part of the drill is important, as 

Shell wants to make it a standard practice that a sulfides test be run every time 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 55 May 2011 

anything unusual happens. In a DRILL ONLY, it may not be necessary to 

perform the sulfides test on the mud. 

6. During the Drill, the Shell Drilling Foreman, Vessel Master, Noble Drilling 

Superintendent, and the H2S Safety Technician will observe to make sure that 

everyone is using their equipment properly. 

7. Resume normal operations. 

8. The Vessel Master, Noble Drilling Superintendent, Shell Drilling Foreman, and 

the H2S Safety Technician will hold a review to discuss results of the drill with 

those participating. 

9. H2S drill performance, new H2S considerations at the facility, and other updated 

H2S information should be discussed at a safety meeting at least monthly. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 56 May 2011 

SECTION B-3 

BREATHING AIR EQUIPMENT DRILLS AND TRAINING SESSIONS 

FOR OFF-DUTY PERSONNEL 

Off-duty personnel include all personnel aboard the drillship with the exception of the 

On-Duty Drilling, Marine and Roustabout Crew, Mudlogger, Mud Engineer, Noble 

Drilling Superintendent, H2S Safety Technician, and Shell Drilling Foreman. 

An H2S drill and training session will be conducted weekly for all off-duty personnel to 

simulate steps that must be taken by personnel who are on their time off when an H2S 

alarm is activated. 

This training will be conducted to instruct personnel in the operation and use of selfcontained breathing apparatus and H2S related emergency equipment, and to review 

various operating procedures in the “H2S Contingency Plan”. 

Initial Drills should include: 

1. General information about the self-contained breathing apparatus (SCBA), 

including air supply time limit, connection to breathing air manifold(s), and proper 

packing and storage. Spectacle Kits for SCBAs should be utilized in place of 

contact lenses or spectacles. 

2. How to put the mask on and test for leaks around face and hose connections. All 

personnel will be informed of the restrictions against having beards. 

These drills should be conducted as often as necessary to acquaint the crews with the 

equipment. After the Shell Drilling Foreman, Vessel Master and/or Drilling 

Superintendent are convinced that all personnel are trained, a weekly drill must be 

conducted. This drill may be initiated any time. Prior to the drill, the Drill and Marine 

crew on duty must be informed that it is only a practice drill. This drill will be initiated by 

the Condition II or Condition III general alarm signal given by the Vessel Master, Drilling 

Superintendent or the Shell Drilling Foreman. At this time, all off-duty personnel will 

immediately get their assigned SCBAs and Type I Life Jackets and report to the 

“MUSTER AREA”. Personnel should be trained to report to the “MUSTER AREA”, then 

to “SAFE BRIEFING AREA” with their emergency equipment within three minutes after 

the alarm has sounded. A training and information session will be conducted after each 

drill to answer any H2S related questions and to cover one or more of the following: 

 Condition I or II alerts and steps to be taken by all personnel. 

 The importance of wind direction when dealing with H2S. 

 Proper use and storage of all types of breathing equipment. 

 Proper use and storage of oxygen resuscitators. 

 The “buddy system” and the procedure for rescuing a person overcome by 

H2S. 

 Responsibilities and duties. 

 Location of H2S safety equipment. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 57 May 2011 

 Other parts of the “H2S Contingency Plan” that should be reviewed. 

NOTE: A record of attendance must be kept for weekly drills and training session. 

These drills must also be documented on the IADC Report and the Shell Daily Drilling 

Report. 

 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 58 May 2011 

SECTION B-4 

HYDROGEN SULFIDE TRAINING CURRICULUM 

At the docks and on the rig; each individual will be asked if they have been cleared by a 

physician to use a respirator. This requirement will be the responsibility of each 

company or individual before coming aboard the rig. 

Each person will be informed on the restrictions of having beards and contact lenses. 

They will also be informed of the availability of spectacle kits. Personnel with beards or 

moustaches that extend past the corners of the mouth must shave and continuously 

restrict the regrowth of facial hair while drilling operations are in progress. Both Noble 

and Shell HSSE representatives will monitor personnel to ensure that the restriction on 

facial hair is enforced. This restriction applies to all personnel aboard the vessel 

including visitors. 

The safety program is outlined in the H2S Contingency Plan. This plan will be available 

on the rig. Each individual will read and sign “Considerations during the Drilling or 

Abandonment of a sour gas well.” 

After the H2S equipment is rigged up, all personnel will be H2S trained and put through a 

drill. Any deficiencies will be corrected. 

Training Completion cards are good for one year and will indicate date of completion or 

expiration. Personnel previously trained on another facility and visiting the drillship must 

attend a “supplemental briefing” on H2S equipment and procedures before beginning 

duty. Visitors without current H2S certification who remain on the facility more than 24 

hours must receive full H2S training given all crew members. A “supplemental briefing” 

will include but not be limited to: location, use and donning of an assigned respirator, 

familiarization with safe briefing areas, alarms with instruction on responsibilities in the 

event of a release and hazards of H2S and SO2. 

Topics for full H2S training shall include, but not limited to the following: 

I. Brief Introduction on H2S 

A. Slide or VCR Presentation (If available) 

B. H2S Material will be distributed 

C. Re-emphasize the properties, toxicity, and hazards of H2S. 

D. Source of SO2. 

II. H2S Detection 

A. Description of H2S sensors 

B. Description of warning system (how it works and its location) 

C. Actual location of H2S sensors 

D. Instruction on use of pump type detector 

E. Use of card detectors, ampoules, or dosimeters 

F. Use of combustible gas detector 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 59 May 2011 

G. Other personnel detectors used 

H. Alarm conditions I or II (10 ppm, 20 ppm) 

III. H2S Protection 

A. Types of breathing apparatus provided (30 minute SCBA & Work Units with 

voice diaphragms for communication) 

B. Principle of how breathing apparatus works. 

C. Demonstration on how to use breathing apparatus. 

D. Location of breathing apparatus. 

IV. Cascade System 

A. Description of Cascade system 

B. How System works 

C. Location of cascade with reference to briefing areas. 

D. How to use cascade system with recharge/refill of SCBA 

E. Importance of wind direction and actual location of windsocks 

F. Purpose of compressor/function 

V. H2S Rescue and First Aid 

A. Importance of wind direction 

B. Safe briefing area 

C. Buddy System 

D. H2S Symptoms 

E. Methods of rescue 

VI. Hands on Training 

A. Donning/familiarization of SCBA 

B. Donning/familiarization of other breathing apparatus/ work units 

C. Familiarization of cascades 

D. Use of O2 resuscitator 

E. Alarm conditions – upwind briefing areas, etc. 

F. Duties and responsibilities of all personnel 

G. Procedures for evacuation 

H. Search and Rescue teams 

VII. Certification 

A. Testing on material covered. 

NOTE: TRAINING AND DRILLS WILL INVOLVE SUPPORT VESSELS TO THE 

EXTENT FEASIBLE AND PRUDENT, AS DETERMINED BY THE VESSEL 

MASTER AND SHELL DRILLING FOREMAN. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 60 May 2011 

Technical Division 

STANDARD FIT TEST FORM 

NAME: ___________________________________ DATE: ______________________ 

ID NUMBER / SSN: _____________________________________________________ 

COMPANY: ___________________________________________________________ 

LOCATION: ___________________________________________________________ 

MASK TYPE: ______________________________ SIZE: _______________________ 

 QUALIATIVE FIT TEST: QUANTATATIVE FIT TEST: 

TEST NUMBER FIT FACTOR P/F 

Test #1 Normal Breathing 

Test #2 Deep Breathing 

Test #3 Head Side to Side 

Test #4 Head Up & Down

Test #5 Talking 

Test #6 Bend and Touch Toes 

Test #7 Normal Breathing 

OVERALL FIT FACTOR OVERALL PASS / FAIL 

 

__________________________________ __________________________________ 

Person Conducting Test Date 

__________________________________ __________________________________ 

 Person Taking Test Date 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 61 May 2011 

Technical Division 

TRAINING ROSTER FORM 

Company: Location: Lease: Chukchi Sea Date:

Drillship: Noble Discoverer Instructor:

Topics Discussed:

Equipment Discussed:

Equipment Demonstrated:

Film Shown: Job Number:

No. NAME (Print) S.S. # Company Signature Date

1 

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 62 May 2011 

SECTION B-5 

EMERGENCY TELEPHONE LISTING 

SHELL GULF OF MEXICO INC. 

A. Initial detection, but less than 10 ppm – Notify the Anchorage Office or residence of 

one of the following: 

Shell Drilling Superintendent TBD 

Shell Drilling Engineer 

Shell SIMOPS Coordinator 

TBD 

TBD 

Shell HSSE Advisor TBD 

 

 

Alaska Emergency and Incident Reporting 

Number: 

877-273-2443 

(Operated by Purcell Security) 907-264-7777 

 

B. Moderate danger – 20 ppm – Notify Anchorage Office or one of above at residence. 

Division office will notify the appropriate authorities. The M.M.S. and Coast Guard 

must be notified. 

DRILLING CONTRACTOR 

Noble Rig Manager TBD 

Noble Anchorage Office TBD 

Noble Houston Office TBD 

 

AREA HOSPITAL FACILITIES 

Providence Alaska Medical 

3200 Providence Dr. 

Anchorage, AK 99508 

Main Line: 907-562-2211 

Emergency Room: 907-261-3111 

Alaska Native Medical Center 

4315 Diplomacy Dr. 

Anchorage, AK 99508 

Main Line: 907-729-1729 

Alaska Regional Medical Center 

2801 DeBarr Rd. 

Anchorage, AK 99508 

Main Line: 907-276-1131 

Emergency Room: 907-264-1232 

 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 63 May 2011 

 

SHELL MEDICAL COORDINATOR 

Beacon Medical 

800 Cordova St. 

Anchorage, AK 99501 

907-222-7612 

907-222-6976 fax 

 

DEPARTMENT OF THE INTERIOR 

US BOEMRE – Alaska District Main Number: 907-334-5200 

Fax: 907-334-2502 

Toll Free: 800-764-2627 

Regional Director – Jim Kendall Office: 907-334-5200 

Regional Supervisor/Field Operations 

After Hours: 

Jeff Walker 

Kyle Monkelien 

Randy Howell 

Office: 907-334-5300 

Fax: 907-334-5302 

907-250-0546 

907-351-2402 

907-382-7814 

 

UNITED STATES COAST GUARD 

ENVIRONMENTAL PROTECTION AGENCY 

National Response Center 

Washington, D.C. 

Office: 800-424-8802 

Office: 202-267-2675 

USCG-Alaska Office: 907-463-2065 

Fax: 907-463-2820 

Toll Free: 800-424-8802 

US Coast Guard Station Office: 907-487-5889 

Region 10, Anchorage, Alaska Office 

222 W. 7th Avenue 

Suite 19 

Anchorage, AK 99513 

Office: 907-271-5083 

Fax: 907-271-3424 

Toll Free: 800-781-0983 

 

 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 64 May 2011 

SECTION B-6 

KEY PERSONNEL TO REMAIN ABOARD 

DURING PARTIAL EVACUATION 

Evacuation of personnel from the Discoverer to the evacuation/standby vessel will be 

conducted using the personnel basket and crane. 

This is a suggested list of minimum personnel to remain on location; however, wellsite 

conditions may dictate that an alternative list be followed. 

Qty. Position 

1 Vessel Master 

2 Shell Drilling Foreman 

1 Maintenance Supervisor 

1 Electrical Supervisor 

1 Mechanical Supervisor 

1 Electronics Technician 

1 Motorman 

1 Medic (SAFETY TECH) 

1 Subsea Engineer 

2 Senior Toolpusher 

2 Toolpushers 

2 Drillers 

2 Assistant Drillers 

4 Floorhands 

1 Deck Supervisor 

2 Roustabouts 

1 Cementer 

2 Mud Loggers 

1 Mud Engineer 

2 Dynamic Safety Technicians 

1 Radio Operator 

1 Crane Operator 

 

NOTE: Once the emergency is clearly defined, the above personnel should then be 

transferred to the evacuation vessel if they will not be needed. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 65 May 2011 

APPENDIX SECTION C 

SECTION C-1 

EQUIPMENT LIST AND INVENTORY 

NO. DESCRIPTION 

215 30 Minute Pressure demand SCBA w/ Pigtail 

50 Hose Line Work Unit w/Escape Cylinder 

6 8-Bottle Cascade of Breathing Air 

2 8-Bottle Cascade of Breathing Air- Drill Floor 

2 2-Bottle Cascade of Breathing Air- Cranes 

3 Oxygen Resuscitator w/ Spare Cylinders 

1 Breathing Air Compressors 

6 Portable H2S Monitors Five Gas (H2S, LEL, CO, SO2, O2) 

2 Sensidyne/Gastech Manual Pump Type Detectors 

10 Boxes H2S Tubes 4L 

10 Boxes H2S Tubes 4H 

10 Boxes SO2 Tubes 5M 

8 Windsock(s) with Pole and Bracket 

2 Megaphones (Bullhorn) w/Spare Batteries 

4 4’ x 8’ H2S Marine Warning Signs 

4 2’ x 3’ Red Warning Light Panels 

8 Primary and Secondary Safe Briefing Area Signs 

2 Flare Pistol 25mm, w/Flares 

10 White Marker Boards with Erasers and Markers 

4 Flashlights w/ spare batteries 

2 Safety harness w/ 150’ Safety Line 

2 First Aid Kit, 24 piece 

10 Operating Condition Signs for Work Areas 

300 Mini Check 

1 Air Lab/ Air Quality Test Kit 

DETECTION AND ALARM SYSTEMS 

NO. DESCRIPTION 

1 H2S Fixed Monitor w/24 Channel Rack 

3 Remote Annunciator Display for Gas Detection (Drill Floor, ECR, Shell Drilling Foreman) 

17 H2S Sensors for Fixed Monitor 

4 Explosion Proof Dual Light/Siren 

5 Hazardous Area Alarms 

20 Indoor Alarms 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 66 May 2011 

EVACUATION VESSEL 

All personnel will have a self-contained breathing apparatus and H2S training. 

Vessels will remain upwind or at a safe distance when not in use. Vessels coming 

alongside will use caution monitoring with detectors to insure H2S or SO2 is not present. 

All personnel on the vessel will don SCBAs when approaching a rig to evacuate 

personnel when H2S is present at 20 ppm TWA15 or SO2 at 2ppm or greater. 

NO. DESCRIPTION 

30 30-minute SCBA Units 

6 10-minute SCBA work units 

15 8-Bottle Cascade of Breathing Air 

14 12-Main Manifold 

2 Distribution Panels 

162 3’ – 5’ Low Pressure Hose Lines 

6 50’ Low Pressure Hose Lines 

2 100’ Low Pressure Hose Lines 

HELICOPTER 

Helicopters will not land if red lights are flashing indicating the presence of H2S. 

Radio communications will be made direct to the drillship to determine if the heliport is 

clear from H2S and SO2. 
Hydrogen Sulfide Contingency Plan 

Shell Gulf of Mexico Inc. 67 

SECTION C-2 

NOBLE DRILLING SUPERINTENDENT’S CHECKLIST: SAFETY EQUIPMENT 

Item Qty Description OK 

Date 

Checked 

Remarks 

1 2 SAFE BRIEFING AREAS 2 1 H2S Safety Equipment Package 3 N/A Sets MY-6 Warning Flags 4 - Zinc Carbonate or Zinc Oxide Equivalent 5 - Continuous type H2S detectors as follows: 5-1 Aft Quarters 5-2 Forward Quarters 5-3 Quarters Intake 5-4 Engine Room Intake 5-5 Sack Room 5-6 Bridge Intake 5-7 Possum Belly 5-8 Mud Return 5-9 Trip Tank 5-10 Mud Pitts 5-11 Pump Room 5-12 Driller’s Cabin 5-13 Cement Unit 5-14 Shale Shaker 5-15 Shale Shaker 5-16 Bell Nipple 5-17 Moon Pool 
Hydrogen Sulfide Contingency Plan 

Shell Gulf of Mexico Inc. 68 

Item Qty Description OK 

Date 

Checked 

Remarks 

6 N/A Electric fans – Placed as follows:  1. Rig Floor  2. Shale Shaker Area  3. Mud Pit and Storage Area 7 1 Forced Air Control Switch in Mudlogging Unit 8 - Safety equipment – as specified in inventory lists ______ _________ _** For more information on these safety equipment items, see Section II, “SAFETY EQUIPMENT”. 
Hydrogen Sulfide Contingency Plan 

Shell Gulf of Mexico Inc. 69 

SECTION C-3 

SAFETY EQUIPMENT CHECKLIST – MUDLOGGER 

To be checked and maintained by Mudlogger 

Item Qty Description OK 

Date 

Checked 

Remarks 

1 2 Self-contained breathing apparatus for all Mud Loggers 2 1 Switch inside the unit that controls the forced air duct into the unit 3 1 Multi-gas Detector w/ H2S 
Hydrogen Sulfide Contingency Plan 

Shell Gulf of Mexico Inc. 70 

SECTION C-4 

SAFETY EQUIPMENT CHECKLIST – H2S SAFETY TECHNICIAN 

To be Checked and Maintained by H2S Safety Technician 

Item Qty Description OK 

Date 

Checked 

Remarks 

1 All The continuous type monitoring units as described in this plan 2 All Breathing Air Cascade System 3 All H2S Alarm System as described in this plan 4 - Self-contained Breathing Apparatus for all H2S Safety Technicians 5 All SCBA for Drillship 
Hydrogen Sulfide Contingency Plan 

Shell Gulf of Mexico Inc. 71 

SECTION C-5 

SAFETY EQUIPMENT CHECKLIST – MUD ENGINEER 

To be checked and maintained 

By Mud Engineer 

Item Qty Description OK 

Date 

Checked 

Remarks OK 

1 1 Self-contained breathing apparatus for all mud engineers 2 - 100% zinc basic carbonate or zinc oxide or equivalent 3 1 Garrett gas train units 4 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 72 May 2011 

SECTION C-6 

SHELL CHECKLIST OF ROUTINE DUTIES 

Perform each week: 

1. Check volume of propane supply for flare ignitors and make sure lines are not 

plugged. Light each burner to verify system. (Backup ignition will be available) 

2. Check all SCBA units for operation: pressure demand regulator, escape bottle air 

volume, supply bottle air volume. 

3. Check breathing equipment mask assembly to see that straps are loosened and 

turned back ready to put on. 

4. Check pressure on breathing equipment air bottles to make sure they are charged to 

full volume. 

5. Check breathing equipment air bottles to make sure all pressure demand regulators 

are working. This requires that the bottle is opened and the mask assembly be put on 

tight enough so that air flows when inhaling. Open one side of mask to be sure air is 

pressured. 

6. Confirm pressure on all air supply bottles. 

7. Perform breathing equipment drills with all on-board personnel. 

8. Check oxygen resuscitators for pressure in oxygen bottle and make sure demand 

regulator is working. 

9. Check the following supplies for availability: 

a. Stretcher 

b. Spot Check Detectors 

c. Safety belts and ropes 

d. Flare gun and flares. 

e. Emergency telephone lists 

f. Spare Air bottles 

g. Spare Oxygen Bottles 

h. Detectors and Tubes 

10. Test the explosion meter to verify that the batteries are good. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 73 May 2011 

SECTION D 

RULES AND REGULATIONS 

SECTION D-1 

30 CFR §250.490 Hydrogen Sulfide Regulations 

(a) What precautions must I take when operating in an H 2 S area? You must: 

(1) Take all necessary and feasible precautions and measures to protect personnel from the toxic 

effects of H2S and to mitigate damage to property and the environment caused by H2S. You must 

follow the requirements of this section when conducting drilling, well-completion/well-workover, and 

production operations in zones with H2S present and when conducting operations in zones where 

the presence of H2S is unknown. You do not need to follow these requirements when operating in 

zones where the absence of H2S has been confirmed; and 

(2) Follow your approved contingency plan. 

(b) Definitions. Terms used in this section have the following meanings: 

Facility means a vessel, a structure, or an artificial island used for drilling, well-completion, wellworkover, and/or production operations. 

H 2 S absent means: 

(1) Drilling, logging, coring, testing, or producing operations have confirmed the absence of H2S in 

concentrations that could potentially result in atmospheric concentrations of 20 ppm or more of H2S; 

or 

(2) Drilling in the surrounding areas and correlation of geological and seismic data with equivalent 

stratigraphic units have confirmed an absence of H2S throughout the area to be drilled. 

H 2 S present means that drilling, logging, coring, testing, or producing operations have confirmed 

the presence of H2S in concentrations and volumes that could potentially result in atmospheric 

concentrations of 20 ppm or more of H2S. 

H 2 S unknown means the designation of a zone or geologic formation where neither the presence 

nor absence of H2S has been confirmed. 

Well-control fluid means drilling mud and completion or workover fluid as appropriate to the 

particular operation being conducted. 

(c) Classifying an area for the presence of H 2 S. You must: 

(1) Request and obtain an approved classification for the area from the Regional Supervisor before 

you begin operations. Classifications are “H2S absent,” H2S present,” or “H2S unknown”; 

(2) Submit your request with your application for permit to drill; 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 74 May 2011 

(3) Support your request with available information such as geologic and geophysical data and 

correlations, well logs, formation tests, cores and analysis of formation fluids; and 

(4) Submit a request for reclassification of a zone when additional data indicate a different 

classification is needed. 

(d) What do I do if conditions change? If you encounter H2S that could potentially result in 

atmospheric concentrations of 20 ppm or more in areas not previously classified as having H2S 

present, you must immediately notify BOE and begin to follow requirements for areas with H2S 

present. 

(e) What are the requirements for conducting simultaneous operations? When conducting any 

combination of drilling, well-completion, well-workover, and production operations simultaneously, 

you must follow the requirements in the section applicable to each individual operation. 

(f) Requirements for submitting an H 2 S Contingency Plan. Before you begin operations, you must 

submit an H2S Contingency Plan to the District Manager for approval. Do not begin operations 

before the District Manager approves your plan. You must keep a copy of the approved plan in the 

field, and you must follow the plan at all times. Your plan must include: 

(1) Safety procedures and rules that you will follow concerning equipment, drills, and smoking; 

(2) Training you provide for employees, contractors, and visitors; 

(3) Job position and title of the person responsible for the overall safety of personnel; 

(4) Other key positions, how these positions fit into your organization, and what the functions, duties, 

and responsibilities of those job positions are; 

(5) Actions that you will take when the concentration of H2S in the atmosphere reaches 20 ppm, who 

will be responsible for those actions, and a description of the audible and visual alarms to be 

activated; 

(6) Briefing areas where personnel will assemble during an H2S alert. You must have at least two 

briefing areas on each facility and use the briefing area that is upwind of the H2S source at any 

given time; 

(7) Criteria you will use to decide when to evacuate the facility and procedures you will use to safely 

evacuate all personnel from the facility by vessel, capsule, or lifeboat. If you use helicopters during 

H2S alerts, describe the types of H2S emergencies during which you consider the risk of helicopter 

activity to be acceptable and the precautions you will take during the flights; 

(8) Procedures you will use to safely position all vessels attendant to the facility. Indicate where you 

will locate the vessels with respect to wind direction. Include the distance from the facility and what 

procedures you will use to safely relocate the vessels in an emergency; 

(9) How you will provide protective-breathing equipment for all personnel, including contractors and 

visitors; 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 75 May 2011 

(10) The agencies and facilities you will notify in case of a release of H2S (that constitutes an 

emergency), how you will notify them, and their telephone numbers. Include all facilities that might 

be exposed to atmospheric concentrations of 20 ppm or more of H2S; 

(11) The medical personnel and facilities you will use if needed, their addresses, and telephone 

numbers; 

(12) H2S detector locations in production facilities producing gas containing 20 ppm or more of H2S. 

Include an “H2S Detector Location Drawing” showing: 

(i) All vessels, flare outlets, wellheads, and other equipment handling production containing H2S; 

(ii) Approximate maximum concentration of H2S in the gas stream; and 

(iii) Location of all H2S sensors included in your contingency plan; 

(13) Operational conditions when you expect to flare gas containing H2S including the estimated 

maximum gas flow rate, H2S concentration, and duration of flaring; 

(14) Your assessment of the risks to personnel during flaring and what precautionary measures you 

will take; 

(15) Primary and alternate methods to ignite the flare and procedures for sustaining ignition and 

monitoring the status of the flare ( i.e. , ignited or extinguished); 

(16) Procedures to shut off the gas to the flare in the event the flare is extinguished; 

(17) Portable or fixed sulphur dioxide (SO2)-detection system(s) you will use to determine SO2

concentration and exposure hazard when H2S is burned; 

(18) Increased monitoring and warning procedures you will take when the SO2 concentration in the 

atmosphere reaches 2 ppm; 

(19) Personnel protection measures or evacuation procedures you will initiate when the SO2

concentration in the atmosphere reaches 5 ppm; 

(20) Engineering controls to protect personnel from SO2; and 

(21) Any special equipment, procedures, or precautions you will use if you conduct any combination 

of drilling, well-completion, well-workover, and production operations simultaneously. 

(g) Training program —(1) When and how often do employees need to be trained? All Shells and 

contract personnel must complete an H2S training program to meet the requirements of this section: 

(i) Before beginning work at the facility; and 

(ii) Each year, within 1 year after completion of the previous class. 
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(2) What training documentation do I need? For each individual working on the platform, either: 

(i) You must have documentation of this training at the facility where the individual is employed; or 

(ii) The employee must carry a training completion card. 

(3) What training do I need to give to visitors and employees previously trained on another facility? 

—(i) Trained employees or contractors transferred from another facility must attend a supplemental 

briefing on your H2S equipment and procedures before beginning duty at your facility; 

(ii) Visitors who will remain on your facility more than 24 hours must receive the training required for 

employees by paragraph (g)(4) of this section; and 

(iii) Visitors who will depart before spending 24 hours on the facility are exempt from the training 

required for employees, but they must, upon arrival, complete a briefing that includes: 

(A) Information on the location and use of an assigned respirator; practice in donning and adjusting 

the assigned respirator; information on the safe briefing areas, alarm system, and hazards of H2S 

and SO2; and 

(B) Instructions on their responsibilities in the event of an H2S release. 

(4) What training must I provide to all other employees? You must train all individuals on your facility 

on the: 

(i) Hazards of H2S and of SO2 and the provisions for personnel safety contained in the H2S 

Contingency Plan; 

(ii) Proper use of safety equipment which the employee may be required to use; 

(iii) Location of protective breathing equipment, H2S detectors and alarms, ventilation equipment, 

briefing areas, warning systems, evacuation procedures, and the direction of prevailing winds; 

(iv) Restrictions and corrective measures concerning beards, spectacles, and contact lenses in 

conformance with ANSI Z88.2, American National Standard for Respiratory Protection (incorporated 

by reference as specified in §250.198); 

(v) Basic first-aid procedures applicable to victims of H2S exposure. During all drills and training 

sessions, you must address procedures for rescue and first aid for H2S victims; 

(vi) Location of: 

(A) The first-aid kit on the facility; 

(B) Resuscitators; and 

(C) Litter or other device on the facility. 
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(vii) Meaning of all warning signals. 

(5) Do I need to post safety information? You must prominently post safety information on the facility 

and on vessels serving the facility ( i.e. , basic first-aid, escape routes, instructions for use of life 

boats, etc.). 

(h) Drills. (1) When and how often do I need to conduct drills on H 2 S safety discussions on the 

facility? You must: 

(i) Conduct a drill for each person at the facility during normal duty hours at least once every 7-day 

period. The drills must consist of a dry-run performance of personnel activities related to assigned 

jobs. 

(ii) At a safety meeting or other meetings of all personnel, discuss drill performance, new H2S 

considerations at the facility, and other updated H2S information at least monthly. 

(2) What documentation do I need? You must keep records of attendance for: 

(i) Drilling, well-completion, and well-workover operations at the facility until operations are 

completed; and 

(ii) Production operations at the facility or at the nearest field office for 1 year. 

(i) Visual and audible warning systems —(1) How must I install wind direction equipment? You must 

install wind-direction equipment in a location visible at all times to individuals on or in the immediate 

vicinity of the facility. 

(2) When do I need to display operational danger signs, display flags, or activate visual or audible 

alarms? —(i) You must display warning signs at all times on facilities with wells capable of 

producing H2S and on facilities that process gas containing H2S in concentrations of 20 ppm or 

more. 

(ii) In addition to the signs, you must activate audible alarms and display flags or activate flashing 

red lights when atmospheric concentration of H2S reaches 20 ppm. 

(3) What are the requirements for signs? Each sign must be a high-visibility yellow color with black 

lettering as follows: 

Letter height Wording 

12 inches Danger. 

 Poisonous Gas. 

 Hydrogen Sulfide. 

7 inches Do not approach if red flag is flying. 

(Use appropriate wording at right) Do not approach if red lights are flashing. 
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(4) May I use existing signs? You may use existing signs containing the words “Danger-Hydrogen 

Sulfide-H2S,” provided the words “Poisonous Gas. Do Not Approach if Red Flag is Flying” or “Red 

Lights are Flashing” in lettering of a minimum of 7 inches in height are displayed on a sign 

immediately adjacent to the existing sign. 

(5) What are the requirements for flashing lights or flags? You must activate a sufficient number of 

lights or hoist a sufficient number of flags to be visible to vessels and aircraft. Each light must be of 

sufficient intensity to be seen by approaching vessels or aircraft any time it is activated (day or 

night). Each flag must be red, rectangular, a minimum width of 3 feet, and a minimum height of 2 

feet. 

(6) What is an audible warning system? An audible warning system is a public address system or 

siren, horn, or other similar warning device with a unique sound used only for H2S. 

(7) Are there any other requirements for visual or audible warning devices? Yes, you must: 

(i) Illuminate all signs and flags at night and under conditions of poor visibility; and 

(ii) Use warning devices that are suitable for the electrical classification of the area. 

(8) What actions must I take when the alarms are activated? When the warning devices are 

activated, the designated responsible persons must inform personnel of the level of danger and 

issue instructions on the initiation of appropriate protective measures. 

(j) H 2 S-detection and H 2 S monitoring equipment —(1) What are the requirements for an H 2 S 

detection system? An H2S detection system must: 

(i) Be capable of sensing a minimum of 10 ppm of H2S in the atmosphere; and 

(ii) Activate audible and visual alarms when the concentration of H2S in the atmosphere reaches 20 

ppm. 

(2) Where must I have sensors for drilling, well-completion, and well-workover operations? You must 

locate sensors at the: 

(i) Bell nipple; 

(ii) Mud-return line receiver tank (possum belly); 

(iii) Pipe-trip tank; 

(iv) Shale shaker; 

(v) Well-control fluid pit area; 

(vi) Driller's station; 

(vii) Living quarters; and 
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Shell Gulf of Mexico Inc. 79 May 2011 

(viii) All other areas where H2S may accumulate. 

(3) Do I need mud sensors? The District Manager may require mud sensors in the possum belly in 

cases where the ambient air sensors in the mud-return system do not consistently detect the 

presence of H2S. 

(4) How often must I observe the sensors? During drilling, well-completion and well-workover 

operations, you must continuously observe the H2S levels indicated by the monitors in the work 

areas during the following operations: 

(i) When you pull a wet string of drill pipe or workover string; 

(ii) When circulating bottoms-up after a drilling break; 

(iii) During cementing operations; 

(iv) During logging operations; and 

(v) When circulating to condition mud or other well-control fluid. 

(5) Where must I have sensors for production operations? On a platform where gas containing H2S 

of 20 ppm or greater is produced, processed, or otherwise handled: 

(i) You must have a sensor in rooms, buildings, deck areas, or low-laying deck areas not otherwise 

covered by paragraph (j)(2) of this section, where atmospheric concentrations of H2S could reach 20 

ppm or more. You must have at least one sensor per 400 square feet of deck area or fractional part 

of 400 square feet; 

(ii) You must have a sensor in buildings where personnel have their living quarters; 

(iii) You must have a sensor within 10 feet of each vessel, compressor, wellhead, manifold, or pump, 

which could release enough H2S to result in atmospheric concentrations of 20 ppm at a distance of 

10 feet from the component; 

(iv) You may use one sensor to detect H2S around multiple pieces of equipment, provided the 

sensor is located no more than 10 feet from each piece, except that you need to use at least two 

sensors to monitor compressors exceeding 50 horsepower; 

(v) You do not need to have sensors near wells that are shut in at the master valve and sealed 

closed; 

(vi) When you determine where to place sensors, you must consider: 

(A) The location of system fittings, flanges, valves, and other devices subject to leaks to the 

atmosphere; and 

(B) Design factors, such as the type of decking and the location of fire walls; and 
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Shell Gulf of Mexico Inc. 80 May 2011 

(vii) The District Manager may require additional sensors or other monitoring capabilities, if 

warranted by site specific conditions. 

(6) How must I functionally test the H 2 S Detectors? —(i) Personnel trained to calibrate the 

particular H2S detector equipment being used must test detectors by exposing them to a known 

concentration in the range of 10 to 30 ppm of H2S. 

(ii) If the results of any functional test are not within 2 ppm or 10 percent, whichever is greater, of the 

applied concentration, recalibrate the instrument. 

(7) How often must I test my detectors? —(i) When conducting drilling, drill stem testing, wellcompletion, or well-workover operations in areas classified as H2S present or H2S unknown, test all 

detectors at least once every 24 hours. When drilling, begin functional testing before the bit is 1,500 

feet (vertically) above the potential H2S zone. 

(ii) When conducting production operations, test all detectors at least every 14 days between tests. 

(iii) If equipment requires calibration as a result of two consecutive functional tests, the District 

Manager may require that H2S-detection and H2S-monitoring equipment be functionally tested and 

calibrated more frequently. 

(8) What documentation must I keep? —(i) You must maintain records of testing and calibrations (in 

the drilling or production operations report, as applicable) at the facility to show the present status 

and history of each device, including dates and details concerning: 

(A) Installation; 

(B) Removal; 

(C) Inspection; 

(D) Repairs; 

(E) Adjustments; and 

(F) Reinstallation. 

(ii) Records must be available for inspection by BOE personnel. 

(9) What are the requirements for nearby vessels? If vessels are stationed overnight alongside 

facilities in areas of H2S present or H2S unknown, you must equip vessels with an H2S-detection 

system that activates audible and visual alarms when the concentration of H2S in the atmosphere 

reaches 20 ppm. This requirement does not apply to vessels positioned upwind and at a safe 

distance from the facility in accordance with the positioning procedure described in the approved 

H2S Contingency Plan. 

(10) What are the requirements for nearby facilities? The District Manager may require you to equip 

nearby facilities with portable or fixed H2S detector(s) and to test and calibrate those detectors. To 
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Shell Gulf of Mexico Inc. 81 May 2011 

invoke this requirement, the District Manager will consider dispersion modeling results from a 

possible release to determine if 20 ppm H2S concentration levels could be exceeded at nearby 

facilities. 

(11) What must I do to protect against SO 2 if I burn gas containing H 2 S? You must: 

(i) Monitor the SO2 concentration in the air with portable or strategically placed fixed devices capable 

of detecting a minimum of 2 ppm of SO2; 

(ii) Take readings at least hourly and at any time personnel detect SO2 odor or nasal irritation; 

(iii) Implement the personnel protective measures specified in the H2S Contingency Plan if the SO2

concentration in the work area reaches 2 ppm; and 

(iv) Calibrate devices every 3 months if you use fixed or portable electronic sensing devices to 

detect SO2. 

(12) May I use alternative measures? You may follow alternative measures instead of those in 

paragraph (j)(11) of this section if you propose and the Regional Supervisor approves the alternative 

measures. 

(13) What are the requirements for protective-breathing equipment? In an area classified as H2S 

present or H2S unknown, you must: 

(i) Provide all personnel, including contractors and visitors on a facility, with immediate access to 

self-contained pressure-demand-type respirators with hoseline capability and breathing time of at 

least 15 minutes. 

(ii) Design, select, use, and maintain respirators in conformance with ANSI Z88.2 (incorporated by 

reference as specified in §250.198). 

(iii) Make available at least two voice-transmission devices, which can be used while wearing a 

respirator, for use by designated personnel. 

(iv) Make spectacle kits available as needed. 

(v) Store protective-breathing equipment in a location that is quickly and easily accessible to all 

personnel. 

(vi) Label all breathing-air bottles as containing breathing-quality air for human use. 

(vii) Ensure that vessels attendant to facilities carry appropriate protective-breathing equipment for 

each crew member. The District Manager may require additional protective-breathing equipment on 

certain vessels attendant to the facility. 

(viii) During H2S alerts, limit helicopter flights to and from facilities to the conditions specified in the 

H2S Contingency Plan. During authorized flights, the flight crew and passengers must use pressure-
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 82 May 2011 

demand-type respirators. You must train all members of flight crews in the use of the particular 

type(s) of respirator equipment made available. 

(ix) As appropriate to the particular operation(s), (production, drilling, well-completion or wellworkover operations, or any combination of them), provide a system of breathing-air manifolds, 

hoses, and masks at the facility and the briefing areas. You must provide a cascade air-bottle 

system for the breathing-air manifolds to refill individual protective-breathing apparatus bottles. The 

cascade air-bottle system may be recharged by a high-pressure compressor suitable for providing 

breathing-quality air, provided the compressor suction is located in an uncontaminated atmosphere. 

(k) Personnel safety equipment —(1) What additional personnel-safety equipment do I need? You 

must ensure that your facility has: 

(i) Portable H2S detectors capable of detecting a 10 ppm concentration of H2S in the air available for 

use by all personnel; 

(ii) Retrieval ropes with safety harnesses to retrieve incapacitated personnel from contaminated 

areas; 

(iii) Chalkboards and/or note pads for communication purposes located on the rig floor, shale-shaker 

area, the cement-pump rooms, well-bay areas, production processing equipment area, gas 

compressor area, and pipeline-pump area; 

(iv) Bull horns and flashing lights; and 

(v) At least three resuscitators on manned facilities, and a number equal to the personnel on board, 

not to exceed three, on normally unmanned facilities, complete with face masks, oxygen bottles, and 

spare oxygen bottles. 

(2) What are the requirements for ventilation equipment? You must: 

(i) Use only explosion-proof ventilation devices; 

(ii) Install ventilation devices in areas where H2S or SO2 may accumulate; and 

(iii) Provide movable ventilation devices in work areas. The movable ventilation devices must be 

multidirectional and capable of dispersing H2S or SO2 vapors away from working personnel. 

(3) What other personnel safety equipment do I need? You must have the following equipment 

readily available on each facility: 

(i) A first-aid kit of appropriate size and content for the number of personnel on the facility; and 

(ii) At least one litter or an equivalent device. 

(l) Do I need to notify MMS in the event of an H 2 S release? You must notify MMS without delay in 

the event of a gas release which results in a 15-minute time-weighted average atmospheric 

concentration of H2S of 20 ppm or more anywhere on the OCS facility. You must report these gas 
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Shell Gulf of Mexico Inc. 83 May 2011 

releases to the District Manager immediately by oral communication, with a written follow-up report 

within 15 days, pursuant to §§250.188 through 250.190. 

(m) Do I need to use special drilling, completion and workover fluids or procedures? When working 

in an area classified as H2S present or H2S unknown: 

(1) You may use either water- or oil-base muds in accordance with §250.300(b)(1). 

(2) If you use water-base well-control fluids, and if ambient air sensors detect H2S, you must 

immediately conduct either the Garrett-Gas-Train test or a comparable test for soluble sulfides to 

confirm the presence of H2S. 

(3) If the concentration detected by air sensors in over 20 ppm, personnel conducting the tests must 

don protective-breathing equipment conforming to paragraph (j)(13) of this section. 

(4) You must maintain on the facility sufficient quantities of additives for the control of H2S, wellcontrol fluid pH, and corrosion equipment. 

(i) Scavengers. You must have scavengers for control of H2S available on the facility. When H2S is 

detected, you must add scavengers as needed. You must suspend drilling until the scavenger is 

circulated throughout the system. 

(ii) Control pH. You must add additives for the control of pH to water-base well-control fluids in 

sufficient quantities to maintain pH of at least 10.0. 

(iii) Corrosion inhibitors. You must add additives to the well-control fluid system as needed for the 

control of corrosion. 

(5) You must degas well-control fluids containing H2S at the optimum location for the particular 

facility. You must collect the gases removed and burn them in a closed flare system conforming to 

paragraph (q)(6) of this section. 

(n) What must I do in the event of a kick? In the event of a kick, you must use one of the following 

alternatives to dispose of the well-influx fluids giving consideration to personnel safety, possible 

environmental damage, and possible facility well-equipment damage: 

(1) Contain the well-fluid influx by shutting in the well and pumping the fluids back into the formation. 

(2) Control the kick by using appropriate well-control techniques to prevent formation fracturing in an 

open hole within the pressure limits of the well equipment (drill pipe, work string, casing, wellhead, 

BOP system, and related equipment). The disposal of H2S and other gases must be through 

pressurized or atmospheric mud-separator equipment depending on volume, pressure and 

concentration of H2S. The equipment must be designed to recover well-control fluids and burn the 

gases separated from the well-control fluid. The well-control fluid must be treated to neutralize H2S 

and restore and maintain the proper quality. 

(o) Well testing in a zone known to contain H 2 S. When testing a well in a zone with H2S present, 

you must do all of the following: 
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Shell Gulf of Mexico Inc. 84 May 2011 

(1) Before starting a well test, conduct safety meetings for all personnel who will be on the facility 

during the test. At the meetings, emphasize the use of protective-breathing equipment, first-aid 

procedures, and the Contingency Plan. Only competent personnel who are trained and are 

knowledgeable of the hazardous effects of H2S must be engaged in these tests. 

(2) Perform well testing with the minimum number of personnel in the immediate vicinity of the rig 

floor and with the appropriate test equipment to safely and adequately perform the test. During the 

test, you must continuously monitor H2S levels. 

(3) Not burn produced gases except through a flare which meets the requirements of paragraph 

(q)(6) of this section. Before flaring gas containing H2S, you must activate SO2 monitoring 

equipment in accordance with paragraph (j)(11) of this section. If you detect SO2 in excess of 2 ppm, 

you must implement the personnel protective measures in your H2S Contingency Plan, required by 

paragraph (f) of this section. You must also follow the requirements of §250.1105. You must pipe 

gases from stored test fluids into the flare outlet and burn them. 

(4) Use downhole test tools and wellhead equipment suitable for H2S service. 

(5) Use tubulars suitable for H2S service. You must not use drill pipe for well testing without the prior 

approval of the District Manager. Water cushions must be thoroughly inhibited in order to prevent 

H2S attack on metals. You must flush the test string fluid treated for this purpose after completion of 

the test. 

(6) Use surface test units and related equipment that is designed for H2S service. 

(p) Metallurgical properties of equipment. When operating in a zone with H2S present, you must use 

equipment that is constructed of materials with metallurgical properties that resist or prevent sulfide 

stress cracking (also known as hydrogen embrittlement, stress corrosion cracking, or H2S 

embrittlement), chloride-stress cracking, hydrogen-induced cracking, and other failure modes. You 

must do all of the following: 

(1) Use tubulars and other equipment, casing, tubing, drill pipe, couplings, flanges, and related 

equipment that is designed for H2S service. 

(2) Use BOP system components, wellhead, pressure-control equipment, and related equipment 

exposed to H2

 S-bearing fluids in conformance with NACE Standard MR0175–03 (incorporated by 

reference as specified in §250.198). 

(3) Use temporary downhole well-security devices such as retrievable packers and bridge plugs that 

are designed for H2S service. 

(4) When producing in zones bearing H2S, use equipment constructed of materials capable of 

resisting or preventing sulfide stress cracking. 

(5) Keep the use of welding to a minimum during the installation or modification of a production 

facility. Welding must be done in a manner that ensures resistance to sulfide stress cracking. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 85 May 2011 

(q) General requirements when operating in an H 2 S zone —(1) Coring operations. When you 

conduct coring operations in H2S-bearing zones, all personnel in the working area must wear 

protective-breathing equipment at least 10 stands in advance of retrieving the core barrel. Cores to 

be transported must be sealed and marked for the presence of H2S. 

(2) Logging operations. You must treat and condition well-control fluid in use for logging operations 

to minimize the effects of H2S on the logging equipment. 

(3) Stripping operations. Personnel must monitor displaced well-control fluid returns and wear 

protective-breathing equipment in the working area when the atmospheric concentration of H2S 

reaches 20 ppm or if the well is under pressure. 

(4) Gas-cut well-control fluid or well kick from H 2 S-bearing zone. If you decide to circulate out a 

kick, personnel in the working area during bottoms-up and extended-kill operations must wear 

protective-breathing equipment. 

(5) Drill- and workover-string design and precautions. Drill- and workover-strings must be designed 

consistent with the anticipated depth, conditions of the hole, and reservoir environment to be 

encountered. You must minimize exposure of the drill- or workover-string to high stresses as much 

as practical and consistent with well conditions. Proper handling techniques must be taken to 

minimize notching and stress concentrations. Precautions must be taken to minimize stresses 

caused by doglegs, improper stiffness ratios, improper torque, whip, abrasive wear on tool joints, 

and joint imbalance. 

(6) Flare system. The flare outlet must be of a diameter that allows easy nonrestricted flow of gas. 

You must locate flare line outlets on the downside of the facility and as far from the facility as is 

feasible, taking into account the prevailing wind directions, the wake effects caused by the facility 

and adjacent structure(s), and the height of all such facilities and structures. You must equip the 

flare outlet with an automatic ignition system including a pilot-light gas source or an equivalent 

system. You must have alternate methods for igniting the flare. You must pipe to the flare system 

used for H2S all vents from production process equipment, tanks, relief valves, burst plates, and 

similar devices. 

(7) Corrosion mitigation. You must use effective means of monitoring and controlling corrosion 

caused by acid gases (H2S and CO2) in both the downhole and surface portions of a production 

system. You must take specific corrosion monitoring and mitigating measures in areas of unusually 

severe corrosion where accumulation of water and/or higher concentration of H2S exists. 

(8) Wireline lubricators. Lubricators which may be exposed to fluids containing H2S must be of H2Sresistant materials. 

(9) Fuel and/or instrument gas. You must not use gas containing H2S for instrument gas. You must 

not use gas containing H2S for fuel gas without the prior approval of the District Manager. 

(10) Sensing lines and devices. Metals used for sensing line and safety-control devices which are 

necessarily exposed to H2S-bearing fluids must be constructed of H2S-corrosion resistant materials 

or coated so as to resist H2S corrosion. 
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Shell Gulf of Mexico Inc. 86 May 2011 

(11) Elastomer seals. You must use H2S-resistant materials for all seals which may be exposed to 

fluids containing H2S. 

(12) Water disposal. If you dispose of produced water by means other than subsurface injection, you 

must submit to the District Manager an analysis of the anticipated H2S content of the water at the 

final treatment vessel and at the discharge point. The District Manager may require that the water be 

treated for removal of H2S. The District Manager may require the submittal of an updated analysis if 

the water disposal rate or the potential H2S content increases. 

(13) Deck drains. You must equip open deck drains with traps or similar devices to prevent the 

escape of H2S gas into the atmosphere. 

(14) Sealed voids. You must take precautions to eliminate sealed spaces in piping designs (e.g., 

slip-on flanges, reinforcing pads) which can be invaded by atomic hydrogen when H2S is present. 

[62 FR 3795, Jan. 27, 1997. Redesignated and amended at 63 FR 29479, 29485, May 29, 1998; 65 

FR 15864, Mar. 24, 2000. Redesignated and amended at 68 FR 8423, 8434, Feb. 20, 2003; 71 FR 

19645, Apr. 17, 2006; 72 FR 12096, Mar. 15, 2007; 72 FR 25201, May 4, 2007] 

 
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Shell Gulf of Mexico Inc. 87 May 2011 

SECTION D-2 

HYDROGEN SULFIDE PINC LIST

This Section Pertains to Areas Classified as H2S Present and H2S Unknown. 

Definitions: H2S present means that drilling, logging, coring, testing, or producing operations 

have confirmed the presence of H2S in concentrations and volumes that could potentially 

result in atmospheric concentrations of 20 ppm or more of H2S.

H2S unknown means the designation of a zone or geological formation where neither the 

presence nor absence of H2S has been confirmed. 

H-100

IS A COPY OF THE APPROVED H2S CONTINGENCY PLAN AVAILABLE IN THE FIELD AREA, 

AND IS THAT PLAN BEING FOLLOWED? 

Authority: 490(f) 

Enforcement Action: W/S 

INSPECTION PROCEDURE:

Verify that an approved plan is available and being followed at the facility at the commencement of 

and throughout all operations during which the H2S Contingency Plan is in effect. 

IF NONCOMPLIANCE EXISTS:

Issue a warning (W) INC if an H2S Contingency Plan is not available. 

Issue a facility shut-in (S) INC if there is not an approved plan or the plan is not being followed. 

INSPECTION FORM:

Enter one item checked per facility. 

 

H-101

ARE AT LEAST TWO SAFE BRIEFING AREAS ESTABLISHED? 

Authority: 490(f)(6) 

Enforcement Action: S 

INSPECTION PROCEDURE:

1. Verify that designated safe briefing areas at the facility are as designated in the approved H2S 

Contingency Plan. 

2. Verify that designated safe briefing area during the inspection period is upwind of operations. 

IF NONCOMPLIANCE EXISTS:

Issue a facility shut-in (S) INC if safe briefing areas: 

1. Are not as approved, 

2. Have not been established, or 

3. During inspection, is not upwind of operations. 

INSPECTION FORM:

Enter one item checked per facility. 

H-102

ARE ALL PERSONNEL INFORMED OF THE HAZARDS OF H2S AND OF SO2 RESULTING 

FROM BURNING H2S, AND INSTRUCTED IN THE PROVISIONS FOR PERSONNEL SAFETY 

CONTAINED IN THE H2S CONTINGENCY PLAN? 

Authority: 490(g)(4)(i) 

Enforcement Action: C 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 88 May 2011 

490(j)(11)(iii) 

INSPECTION PROCEDURE:

Inspect training session records to verify that personnel were instructed and informed as required. 

IF NONCOMPLIANCE EXISTS:

Issue a component shut-in (C) INC to remove any person from the facility that has not received the 

required instructions. 

INSPECTION FORM:

Enter one item checked per facility. 

H-103

ARE ALL PERSONNEL INSTRUCTED IN THE USE OF SAFETY EQUIPMENT WHICH THEY 

MAY BE REQUIRED TO USE? 

Authority: 490(g)(4)(ii) 

Enforcement Action: C 

INSPECTION PROCEDURE:

Inspect training session records to verify that all personnel were instructed and informed as 

required. 

IF NONCOMPLIANCE EXISTS:

Issue a component shut-in (C) INC to remove any personnel from the facility that have not received 

the required instructions. 

INSPECTION FORM:

Enter one item checked per facility. 

H-104

ARE ALL PERSONNEL INFORMED OF THE LOCATION OF PROTECTIVE-BREATHING 

EQUIPMENT, H2S DETECTORS AND ALARMS, VENTILATION EQUIPMENT, BRIEFING 

AREAS, WARNING SYSTEMS, EVACUATION PROCEDURES, AND THE DIRECTION OF THE 

PREVAILING WINDS? 

Authority: 490(g)(4)(iii) 

Enforcement Action: C 

INSPECTION PROCEDURE:

Inspect training session records to verify that all personnel were instructed and informed as 

required. 

IF NONCOMPLIANCE EXISTS:

Issue a component shut-in (C) INC to remove any personnel from the facility that has not received 

the required instructions. 

INSPECTION FORM:

Enter one item checked per facility. 

 

H-105

ARE ALL PERSONNEL INFORMED OF THE RESTRICTIONS AND CORRECTIVE MEASURES 

CONCERNING BEARDS, SPECTACLES, AND CONTACT LENSES IN CONFORMANCE WITH 

ANSI Z88.2? 

Authority: 198(e) 

Enforcement Action: C 

490(g)(4)(iv) 

INSPECTION PROCEDURE:
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 89 May 2011 

Inspect training session records to verify that all personnel were instructed and informed as 

required. 

IF NONCOMPLIANCE EXISTS:

Issue a component shut-in (C) INC to remove any personnel from the facility that have not received 

the required instructions. 

INSPECTION FORM:

Enter one item checked per facility. 

H-106

IS SAFETY INFORMATION PROMINENTLY POSTED ON THE FACILITY? 

Authority: 490(g)(5) 

Enforcement Action: W 

INSPECTION PROCEDURE:

Visually observe the facility to verify the posting of safety information. 

IF NONCOMPLIANCE EXISTS:

Issue a warning (W) INC if safety information is not prominently posted on the facility. 

INSPECTION FORM:

Enter one item checked per facility. 

H-107

IS SAFETY INFORMATION PROMINENTLY POSTED ON VESSELS SERVING THE FACILITY? 

Authority: 490(g)(5) 

Enforcement Action: W 

INSPECTION PROCEDURE:

Visually inspect the vessel to verify the posting of safety information. 

IF NONCOMPLIANCE EXISTS:

Issue a warning (W) INC if safety information is not prominently posted on vessels serving the 

facility. 

INSPECTION FORM:

Enter one item checked for each vessel inspected. 

H-108

DO ALL SHELL AND CONTRACT PERSONNEL RECEIVE A TRAINING SESSION BEFORE 

BEGINNING WORK AT THE FACILITY AND AGAIN WITHIN 1 YEAR AFTER COMPLETION 

OF THE PREVIOUS CLASS? 

Authority: 490(g)(1)(i) 

Enforcement Action: C 

490(g)(1)(ii) 

INSPECTION PROCEDURE:

1. Verify that all Shell and contract personnel arriving at the facility have received a training session 

before beginning work. 

2. Verify that the Shell and contract personnel have again received that training within 1 year after 

completion of the previous class. 

IF NONCOMPLIANCE EXISTS:

Issue a component shut-in (C) INC if, during the inspection, the inspector observes any Shell or 

contract personnel arriving at the facility who does not receive a training session before beginning 

work or has not received that training within 1 year after completion of the previous class. 

INSPECTION FORM:
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 90 May 2011 

Enter one item checked per facility. 

H-109

DOES EACH PERSON PARTICIPATE IN A DRILL DURING NORMAL DUTY HOURS AT LEAST 

ONCE EVERY 7-DAY PERIOD? 

Authority: 490(h)(1)(i) 

Enforcement Action: W/C 

INSPECTION PROCEDURE:

Verify that all personnel have participated in a drill during normal duty hours at least once in every 7-

day period after duty begins. 

Note: Duty begins upon arrival at the facility. 

IF NONCOMPLIANCE EXISTS:

Issue a warning (W) INC if records do not indicate that any person(s) did not participate in a drill at 

least once in every 7-day period after duty began. 

Issue a component shut-in (C) INC if individual personnel has not participated in a drill during 

normal duty hours at least once every 7-day period. 

INSPECTION FORM:

Enter one item checked per facility. 

H-111

ARE RECORDS OF ATTENDANCE FOR TRAINING MAINTAINED AT THE FACILITY OR 

DOES THE EMPLOYEE CARRY A TRAINING COMPLETION CARD? 

Authority: 490(g)(2)(i) 

Enforcement Action: W 

490(g)(2)(ii) 

INSPECTION PROCEDURE:

Request to see the records of attendance at the weekly drills and training sessions. 

IF NONCOMPLIANCE EXISTS:

Issue a warning (W) INC if: 

1. The records are not available. 

2. The records are incomplete. 

INSPECTION FORM:

Enter one item checked per facility. 

H-113

IS A FIRST-AID KIT, OF APPROPRIATE SIZE AND CONTENT, READILY AVAILABLE FOR THE 

NUMBER OF PERSONNEL ON THE FACILITY? 

Authority: 490(k)(3)(i) 

Enforcement Action: W 

INSPECTION PROCEDURE:

Visually inspect the facility to verify that a first-aid kit of appropriate size and content is readily 

available. 

IF NONCOMPLIANCE EXISTS:

Issue a warning (W) INC if: 

1. There is no first-aid kit. 

2. The first-aid kit is of insufficient size or content. 

3. The first aid kit is not readily available. 

INSPECTION FORM:
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 91 May 2011 

Enter one item checked for each kit inspected. 

H-114

ARE THERE AT LEAST THREE RESUSCITATORS ON MANNED FACILITIES, AND A NUMBER 

EQUAL TO THE PERSONNEL ON BOARD, NOT TO EXCEED THREE, ON NORMALLY 

UNMANNED FACILITIES (COMPLETE WITH FACE MASKS, OXYGEN BOTTLES, SPARE 

OXYGEN BOTTLES) AND ARE THESE ITEMS READILY AVAILABLE? 

Authority: 490(k)(1)(v) 

Enforcement Action: C 

INSPECTION PROCEDURE:

1. Visually inspect the facility to verify that at least three resuscitators complete with a face mask 

and oxygen bottle are available. 

2. Visually inspect the facility to verify that spare oxygen bottles are readily available. 

IF NONCOMPLIANCE EXISTS:

Issue a facility shut-in (C) INC if: 

1. The facility is not equipped with at least three resuscitators complete with face masks and oxygen 

bottles. 

2. The facility does not have spare oxygen bottles. 

3. The resuscitators and oxygen bottles are not readily available. 

INSPECTION FORM:

Enter one item checked per facility. 

H-115

IS THERE AT LEAST ONE LITTER OR AN EQUIVALENT DEVICE ON THE FACILITY AND 

READILY AVAILABLE FOR USE? 

Authority: 490(k)(3)(ii) 

Enforcement Action: W 

INSPECTION PROCEDURE:

Visually inspect the facility to verify that there is at least one litter or an equivalent device readily 

available on the facility. 

IF NONCOMPLIANCE EXISTS:

Issue a warning (W) INC if there is not at least one litter or an equivalent device readily available. 

INSPECTION FORM:

Enter one item checked per facility. 

H-117

IS WIND-DIRECTION EQUIPMENT INSTALLED IN LOCATIONS VISIBLE AT ALL TIMES TO 

INDIVIDUALS ON OR IN THE IMMEDIATE VICINITY OF THE FACILITY?

Authority: 490(i)(1) 

Enforcement Action: S 

INSPECTION PROCEDURE:

Visually verify that visible wind-direction equipment has been installed at prominent locations. Wind 

direction equipment includes windsocks, flags, and streamers. 

IF NONCOMPLIANCE EXISTS:

Issue a facility shut-in (S) INC if wind-direction equipment is not visible or has not been installed in 

prominent locations. 

INSPECTION FORM:

Enter one item checked per facility. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 92 May 2011 

H-118

ARE OPERATIONAL DANGER SIGNS DISPLAYED AT ALL TIMES ON FACILITIES WITH 

WELLS CAPABLE OF PRODUCING H2S GAS IN CONCENTRATIONS OF 20 PPM OR MORE? 

Authority: 490(i)(2)(i) 

Enforcement Action: W 

INSPECTION PROCEDURE:

Inspect the signs and flags to verify that installation is as required. 

Signs shall: 

1. Be installed on each side of the facility. 

2. Be a minimum width of 8 feet and a minimum height of 4 feet. 

3. Be a high visibility yellow color with black lettering a minimum of 12 inches in height. 

4. Read "DANGER - HYDROGEN SULFIDE - H2S". 

5. Be illuminated at night and under conditions of poor visibility. 

6. Be displayed when concentrations of H2S reach 20 ppm. 

Red Flags shall: 

1. Be visible to aircraft and watercraft when hoisted. 

2. Be a minimum width of 3 feet and a minimum height of 2 feet. 

3. Be illuminated at night and under conditions of poor visibility, and 

4. Be displayed when concentrations of H2S reach 50 ppm. 

IF NONCOMPLIANCE EXISTS:

Issue a warning (W) INC if: 

1. Signs or flags are not displayed as required. 

2. Signs or flags are not available for use. 

INSPECTION FORM:

Enter one item checked per facility. 

H-120

DOES THE FACILITY HAVE AN H2S-DETECTION AND H2S-MONITORING SYSTEM WHICH IS 

CAPABLE OF SENSING A MINIMUM OF 10 PPM H2S AND WHICH ACTIVATES AUDIBLE AND 

VISUAL ALARMS WHEN THE ATMOSPHERIC CONCENTRATION REACHES 20 PPM AND 

ARE THESE SENSING DEVICES LOCATED AT THE BELL NIPPLE, MUD RETURN LINE 

RECEIVER TANK (POSSUM BELLY), PIPE TRIP TANK, SHALE SHAKER, WELL-CONTROL 

FLUID PIT AREA, DRILLER'S STATION, LIVING QUARTERS, AND OTHER AREAS WHERE 

H2S MIGHT ACCUMULATE? 

Authority: 490(j)(1)(i) 

Enforcement Action: S 

490(j)(2)(i) 

490(j)(2)(ii) 

490(j)(2)(iii) 

490(j)(2)(iv) 

490(j)(2)(v) 

490(j)(2)(vi) 

490(j)(2)(vii) 

490(j)(2)(viii) 

INSPECTION PROCEDURE:

1. Visually verify that detection and monitoring equipment (sensors) is installed at: 

A. Bell nipple. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 93 May 2011 

B. Mud return line receiver tank (possum belly). 

C. Pipe trip tank. 

D. Shale shaker. 

E. Well-control fluid pit area. 

F. Driller’s station. 

G. Living quarters (drilling personnel). 

H. Other areas where H2S may accumulate. 

2. Have Shell test equipment for operation. 

IF NONCOMPLIANCE EXISTS:

Issue a facility shut-in (S) INC if H2S detection and monitoring equipment is not: 

1. Installed at the required locations. 

2. Operable. 

INSPECTION FORM:

Enter one item checked for each location inspected. 

H-121 

ARE SENSORS LOCATED IN ROOMS, BUILDINGS, DECK AREAS, OR LOW-LAYING DECK 

AREAS NOT OTHERWISE COVERED BY 30 CFR 250.490(j)? 

Authority: 490(j)(5)(i) 

Enforcement Action: S 

INSPECTION PROCEDURE: 

Verify that sensors are located in rooms, buildings, deck areas, or low-laying deck areas not 

otherwise 

covered by 30 CFR 250.490(j). 

IF NONCOMPLIANCE EXISTS: 

Issue a facility shut-in (S) INC if sensors are not located in rooms, buildings, deck areas, or lowlaying deck 

areas not otherwise covered by 30 CFR 250.490(j). 

INSPECTION FORM: 

Enter one item checked for each location inspected. 

H-122 

IS AT LEAST ONE SENSOR INSTALLED PER 400 SQUARE FEET OF DECK AREA OR 

FRACTIONAL PART THEREOF (OR AS OTHERWISE APPROVED BY THE DISTRICT 

SUPERVISOR)? 

Authority: 490(j)(5)(i) 

Enforcement Action: S 

INSPECTION PROCEDURE: 

Verify that there is at least one sensor installed per 400 square feet of deck area or fractional part 

thereof (or 

as otherwise approved by the District Supervisor). 

IF NONCOMPLIANCE EXISTS: 

Issue a facility shut-in (S) INC if there is not at least one sensor installed per 400 square feet of deck 

area or 

a fractional part thereof (or as otherwise approved by the District Supervisor). 

INSPECTION FORM: 

Enter one item checked for each area inspected. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 94 May 2011 

H-123 

IS A SENSOR LOCATED IN BUILDINGS WHERE PERSONNEL HAVE THEIR LIVING 

QUARTERS? 

Authority: 490(j)(5)(ii) 

Enforcement Action: S 

INSPECTION PROCEDURE: 

Verify that a sensor is located in buildings where personnel have their living quarters. 

IF NONCOMPLIANCE EXISTS: 

Issue a facility shut-in (S) INC if there is not a sensor located in buildings where personnel have 

their living quarters. 

INSPECTION FORM: 

Enter one item checked for each building inspected. 

H-124 

IS ONE SENSOR LOCATED WITHIN 10 FEET OF EACH VESSEL, COMPRESSOR, WELLHEAD, 

MANIFOLD, OR PUMP (OR AS OTHERWISE APPROVED BY THE DISTRICT SUPERVISOR)? 

Authority: 490(j)(5)(iii) 

Enforcement Action: C 

INSPECTION PROCEDURE: 

Inspect to verify that there is one sensor located within 10 feet of each vessel, compressor, 

wellhead, manifold, or pump (or as otherwise approved by the District Supervisor). 

IF NONCOMPLIANCE EXISTS: 

Issue a component shut-in (C) INC if a sensor is not located within 10 feet of each vessel, 

compressor, wellhead, manifold, or pump (or as otherwise approved by the District Supervisor). 

INSPECTION FORM: 

Enter one item checked for each component inspected. 

H-125 

IF ONE SENSOR IS USED TO COVER MULTIPLE PIECES OF EQUIPMENT, IS EACH PIECE 

OF EQUIPMENT NO MORE THAN 10 FEET FROM THE SENSOR (OR AS OTHERWISE 

APPROVED BY THE DISTRICT SUPERVISOR)? 

Authority: 490(j)(5)(iv) 

Enforcement Action: C 

INSPECTION PROCEDURE: 

Verify that if one sensor is used to cover multiple pieces of equipment, each piece of equipment is 

no more than 10 feet from the sensor (or as otherwise approved by the District Supervisor). 

IF NONCOMPLIANCE EXISTS: 

Issue a component shut-in (C) INC if pieces of the equipment are more than 10 feet from the sensor 

(or as otherwise approved by the District Supervisor). 

INSPECTION FORM: 

Enter one item checked for multiple pieces of equipment inspected. 

H-126

IS THE H2S-DETECTION SYSTEM RECALIBRATED WHEN FUNCTIONAL TESTS ARE NOT 

WITHIN 2 PPM OR 10 PERCENT, WHICHEVER IS GREATER, OF THE APPLIED 

CONCENTRATIONS (OR AS OTHERWISE APPROVED BY THE DISTRICT SUPERVISOR)? 

Authority: 490(j)(6)(ii) 

Enforcement Action: C 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 95 May 2011 

INSPECTION PROCEDURE:

Check Shell's records to verify that the H2S-detection and H2S-monitoring equipment is recalibrated 

as required (or as otherwise approved by the District Supervisor). 

IF NONCOMPLIANCE EXISTS:

Issue a component shut-in (C) INC on the monitored area if the H2S-detection and H2S-monitoring 

equipment has not been recalibrated as required (or as otherwise approved by the District 

Supervisor). 

INSPECTION FORM:

Enter one item checked per facility. 

H-127

ARE PORTABLE H2S DETECTORS CAPABLE OF DETECTING 10 PPM CONCENTRATIONS 

OF 

H2S GAS IN AIR AND AVAILABLE FOR USE BY ALL PERSONNEL? 

Authority: 490(k)(1)(i) 

Enforcement Action: W 

INSPECTION PROCEDURE: 

Verify that portable H2S detectors capable of detecting 10 ppm concentrations of H2S gas in air are 

available for use by all personnel. 

IF NONCOMPLIANCE EXISTS: 

Issue a warning (W) INC if portable H2S detectors are not capable of detecting 10 ppm 

concentrations of H2S gas in air and available for use by all personnel. 

INSPECTION FORM: 

Enter one item checked for each portable detector checked. 

H-128 

ARE PRESSURE-DEMAND TYPE RESPIRATORS WITH HOSELINE CAPABILITY AND 

BREATHING TIME OF AT LEAST 15 MINUTES IMMEDIATELY AVAILABLE AND EASILY 

ACCESSIBLE TO ALL PERSONNEL ON THE FACILITY INCONFORMANCE WITH ANSI Z88.2? 

Authority: 490(j)(13)(i) 

Enforcement Action: S 

490(j)(13)(ii) 

490(j)(13)(v) 

INSPECTION PROCEDURE: 

1. Inspect the facility to verify that all pressure-demand type respirators with hoseline capability and 

breathing time of at least 15 minutes are available and easily accessible to all personnel on the 

facility and in conformance with ANSI Z88.2. 

2. Visually inspect gauges to verify that the air tanks are full. 

IF NONCOMPLIANCE EXISTS: 

Issue a facility shut-in (S) INC if all pressure-demand type respirators with hoseline capability of at 

least 15 minutes of breathing time are not accessible to all personnel on the facility and in 

conformance with ANSI Z88.2. 

INSPECTION FORM: 

Enter one item checked per facility. 

H-129 

ARE AT LEAST TWO VOICE TRANSMISSION DEVICES, WHICH CAN BE USED WHILE 

WEARING A RESPIRATOR, AVAILABLE FOR USE BY DESIGNATED PERSONNEL? 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 96 May 2011 

Authority: 490(j)(13)(iii) 

Enforcement Action: W 

INSPECTION PROCEDURE: 

Verify that at least two voice transmission devices, which can be used while wearing a respirator, 

are available for use by designated personnel. 

IF NONCOMPLIANCE EXISTS: 

Issue a warning (W) INC if there are not at least two voice transmission devices on the facility. 

INSPECTION FORM: 

Enter one item checked per facility. 

H-131

IS EACH BREATHING-AIR BOTTLE LABELED AS CONTAINING BREATHING-QUALITY AIR 

FOR HUMAN USE? 

Authority: 490(j)(13)(vi)

Enforcement Action: C/S 

INSPECTION PROCEDURE:

Visually inspect the breathing-air bottles to verify that they are labeled as containing breathingquality air for human use. 

IF NONCOMPLIANCE EXISTS:

Issue a component shut-in (C) INC if a few of the breathing-air bottles are not labeled as containing 

breathing-quality air for human use but have ample supply of bottles that are labeled. 

Issue a facility shut-in (S) INC if none of the breathing-air bottles are labeled as containing 

breathing-quality air for human use. 

INSPECTION FORM:

Enter one item checked for each bottle inspected. 

H-132

DO VESSELS ATTENDANT TO FACILITIES CARRY APPROPRIATE 

PROTECTIVE-BREATHING EQUIPMENT FOR EACH CREW MEMBER? 

Authority: 490(j)(13)(vii) 

Enforcement Action: C 

INSPECTION PROCEDURE:

1. If conditions permit, inspect each attendant vessel to verify that it carries sufficient protectivebreathing equipment for each crew member. 

2. If the District Supervisor has required additional protective-breathing equipment for vessels, verify 

that the additional equipment is on board. 

IF NONCOMPLIANCE EXISTS:

Issue a component shut-in (C) INC to remove the vessel if: 

1. The vessel does not carry sufficient protective-breathing equipment for each crew member. 

2. The vessel does not carry the additional equipment required by the District Supervisor. 

INSPECTION FORM:

Enter one item checked for each vessel inspected. 

H-133

FOR AUTHORIZED FLIGHTS DURING H2S ALERTS, ARE HELICOPTER FLIGHTS TO AND 

FROM THE FACILITY LIMITED TO THE CONDITIONS SPECIFIED IN THE H2S CONTINGENCY 

PLAN? 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 97 May 2011 

Authority: 490(j)(13)(viii) 

Enforcement Action: C 

INSPECTION PROCEDURE:

Review contingency plans to determine when a flight is considered an authorized flight. 

IF NONCOMPLIANCE EXISTS:

Issue a component shut-in (C) INC if unauthorized flights are witnessed during an H2S alert. 

INSPECTION FORM:

Enter one item checked for each unauthorized flight. 

H-134 

DURING AUTHORIZED FLIGHTS, DO THE FLIGHT CREW AND PASSENGERS USE 

PRESSURE-DEMAND TYPE RESPIRATORS? 

Authority: 490(j)(13)(viii) 

Enforcement Action: C 

INSPECTION PROCEDURE: 

During an authorized H2S alert flight, observe if the flight crew and passengers use pressuredemand type respirators. 

IF NONCOMPLIANCE EXISTS: 

Issue a component shut-in (C) INC if the crew and passengers are not using pressure-demand type 

respirators. 

INSPECTION FORM: 

Enter one item for each crew member and passenger inspected. 

H-135

ARE ALL MEMBERS OF THE FLIGHT CREW TRAINED IN THE USE OF THE PARTICULAR 

TYPE(S) OF RESPIRATOR EQUIPMENT MADE AVAILABLE? 

Authority: 490(j)(13)(viii) 

Enforcement Action: C 

INSPECTION PROCEDURE:

Verify that all members of the flight crew have been trained in the use of the particular type 

equipment aboard the aircraft or stored at the heliport. 

IF NONCOMPLIANCE EXISTS:

Issue a component shut-in (C) INC to remove the helicopter if all members of the flight crew have 

not been trained in the use of the equipment. 

INSPECTION FORM:

Enter one item checked for each flight crew inspected. 

H-136

AS APPROPRIATE TO THE PARTICULAR OPERATION(S), (PRODUCTION, DRILLING, 

WELL-COMPLETION/WORKOVER, OR ANY COMBINATION THEREOF), IS A SYSTEM OF 

BREATHING-AIR MANIFOLDS, HOSES, AND MASKS PROVIDED ON THE FACILITY AND IN 

THE BRIEFING AREAS? 

Authority: 490(j)(13)(ix) 

Enforcement Action: S 

INSPECTION PROCEDURE:

Visually inspect the facility, including the briefing areas, to verify that a system of breathing-air 

manifolds, hoses, and masks has been installed as approved in the H2S Contingency Plan. 

IF NONCOMPLIANCE EXISTS:
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 98 May 2011 

Issue a facility shut-in (S) INC if a system of breathing-air manifolds, hoses, and masks has not 

been installed as approved in the H2S Contingency Plan. 

INSPECTION FORM:

Enter one item checked per facility. 

H-137

IS A CASCADE AIR-BOTTLE SYSTEM PROVIDED FOR THE BREATHING-AIR MANIFOLDS 

AND TO REFILL INDIVIDUAL PROTECTIVE-BREATHING APPARATUS BOTTLES? 

Authority: 490(j)(13)(ix) 

Enforcement Action: S 

INSPECTION PROCEDURE:

Visually inspect the facility to verify that the cascade air-bottle system has been installed as 

approved in the H2S Contingency Plan. 

IF NONCOMPLIANCE EXISTS:

Issue a facility shut-in (S) INC if a cascade air-bottle system has not been installed as approved in 

the H2S Contingency Plan. 

INSPECTION FORM:

Enter one item checked per facility. 

H-138

IF THE CASCADE AIR-BOTTLE SYSTEM IS RECHARGED BY A HIGH-PRESSURE 

COMPRESSOR SUITABLE FOR PROVIDING BREATHING-QUALITY AIR, IS THE 

COMPRESSOR SUCTION LOCATED IN AN UNCONTAMINATED ATMOSPHERE? 

Authority: 490(j)(13)(ix) 

Enforcement Action: S 

INSPECTION PROCEDURE:

Visually inspect the compressor to verify that: 

1. It is suitable for providing breathing-quality air. 

2. The compressor suction is located in an uncontaminated atmosphere. 

IF NONCOMPLIANCE EXISTS:

Issue a facility shut-in (S) INC if: 

1. The high-pressure compressor is not suitable for providing breathing-quality air, or 

2. The compressor suction is located in a contaminated atmosphere. 

INSPECTION FORM:

Enter one item checked per facility. 

H-140

ARE RETRIEVAL ROPES WITH SAFETY HARNESSES AVAILABLE TO RETRIEVE 

INCAPACITATED PERSONNEL FROM CONTAMINATED AREAS? 

Authority: 490(k)(1)(ii) 

Enforcement Action: W 

INSPECTION PROCEDURE:

Visually inspect the facility to verify that retrieval ropes with safety harnesses are available as 

approved in the H2S Contingency Plan. 

IF NONCOMPLIANCE EXISTS:

Issue a warning (W) INC if retrieval ropes with safety harnesses are not available. 

INSPECTION FORM:

Enter one item checked per facility. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 99 May 2011 

H-141

ARE CHALKBOARDS AND/OR NOTE PADS AVAILABLE FOR COMMUNICATION PURPOSES 

LOCATED ON THE RIG FLOOR, SHALE-SHAKER AREA, THE CEMENT-PUMP ROOMS, 

WELL-BAY AREAS, PRODUCTION PROCESSING EQUIPMENT AREA, GAS COMPRESSOR 

AREA, AND PIPELINE-PUMP AREA? 

Authority: 490(k)(1)(iii) 

Enforcement Action: W 

INSPECTION PROCEDURE:

Visually inspect to verify that chalkboards and/or note pads are available at the following locations 

as approved in the H2S Contingency Plan: 

1. Rig floor. 

2. Shale-shaker area. 

3. Cement-pump rooms. 

4. Well-bay areas. 

5. Production processing equipment area. 

6. Gas compressor area. 

7. Pipeline-pump area. 

IF NONCOMPLIANCE EXISTS:

Issue a warning (W) INC if chalkboards and/or note pads are not available at the required locations. 

INSPECTION FORM:

Enter one item checked for each location inspected. 

H-142 

ARE BULL HORNS AND FLASHING LIGHTS AVAILABLE? 

Authority: 490(k)(1)(iv) 

Enforcement Action: S 

INSPECTION PROCEDURE:

Visually inspect the facility to verify that the following equipment is available and operable as 

approved in the H2S Contingency Plan: 

Bull horns. 

Flashing lights. 

IF NONCOMPLIANCE EXISTS:

Issue a facility shut-in (S) INC if operable bull horns and flashing lights are not available. 

INSPECTION FORM:

Enter one item checked per facility. 

H-143 

ARE AUDIBLE ALARMS AND DISPLAY FLAGS OR FLASHING RED LIGHTS AVAILABLE 

FOR USE ON FACILITIES WHEN ATMOSPHERIC CONCENTRATIONS OF H2S REACH 20 

PPM AND ARE SIGNS AND FLAGS CAPABLE OF BEING ILLUMINATED AT NIGHT AND 

UNDER CONDITIONS OF POOR VISIBILITY? 

Authority: 490(i)(2)(ii) 

Enforcement Action: S 

490(i)(5) 

490(i)(7)(i) 

INSPECTION PROCEDURE: 

Test and visually inspect: 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 100 May 2011 

1. Audible alarms 

2. Display flags or flashing red lights 

3. Signs and flags capable of being illuminated at night and under conditions of poor visibility. 

IF NONCOMPLIANCE EXISTS: 

Issue a facility shut-in (S) INC if the above items are not available for use on the facility. 

INSPECTION FORM: 

Enter one item checked per facility. 

H-144

ARE ALL VENTILATION DEVICES EXPLOSION-PROOF AND SITUATED IN AREAS WHERE 

H2S OR SO2 MAY ACCUMULATE? 

Authority: 490(k)(2)(i) 

Enforcement Action: C/S 

490(k)(2)(ii) 

INSPECTION PROCEDURE:

1. Visually inspect all ventilation devices to verify that they are explosion-proof. 

2. Visually inspect the facility to verify that ventilation devices are situated in areas where H2S and 

SO2 may accumulate as approved in the H2S Contingency Plan. 

IF NONCOMPLIANCE EXISTS:

Issue a component shut-in (C) INC for the ventilation device if it is not explosion-proof. 

Issue a facility shut-in (S) INC if ventilation devices are not situated as approved in the H2S 

Contingency Plan in areas where H2S and SO2 may accumulate. 

INSPECTION FORM:

Enter one item checked for each device inspected. 

H-145

ARE MOVABLE, MULTIDIRECTIONAL VENTILATION DEVICES CAPABLE OF DISPERSING 

H2S OR SO2 VAPORS AWAY FROM WORKING PERSONNEL PROVIDED IN WORK AREAS? 

Authority: 490(k)(2)(iii) 

Enforcement Action: C 

INSPECTION PROCEDURE:

Visually inspect work areas to verify that movable, multidirectional ventilation devices capable of 

dispersing H2S and SO2 vapors are provided. 

IF NONCOMPLIANCE EXISTS:

Issue a component shut-in (C) INC for the work area if movable, multidirectional ventilation devices 

capable of dispersing H2S and SO2 vapors are not provided. 

INSPECTION FORM:

Enter one item checked per facility. 

H-146

IF WATER-BASED, WELL-CONTROL FLUIDS ARE USED, AND IF H2S IS DETECTED BY AIR 

SENSORS, HAS THE GARRETT-GAS-TRAIN TEST OR COMPARABLE TEST TECHNIQUES 

FOR SOLUBLE SULFIDES BEEN CONDUCTED? 

Authority: 490(m)(2) 

Enforcement Action: W 

INSPECTION PROCEDURE:

1. Check Shell's records to verify that the Garrett-Gas-Train test or comparable test for soluble 

sulfides has been conducted if H2S was detected when using water-base well-control fluids. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 101 May 2011 

2. If the concentration detected by air sensors is in excess of 20 ppm, personnel conducting the 

tests shall don protective-breathing equipment. 

Note: The Garrett-Gas-Train test is described in API RP 13B, Appendix A.16. 

IF NONCOMPLIANCE EXISTS:

Issue a warning (W) INC if the Garrett-Gas-Train test or comparable test for soluble sulfides has not 

been conducted when H2S was detected. 

INSPECTION FORM:

Enter one item checked per facility. 

H-147

ARE SUFFICIENT QUANTITIES OF ADDITIVES (SCAVENGERS, pH, AND CORROSION 

CONTROL) MAINTAINED ON THE FACILITY? 

Authority: 490(m)(4)(i) 

Enforcement Action: S 

490(m)(4)(ii) 

490(m)(4)(iii) 

INSPECTION PROCEDURE:

Visually inspect the facility to verify that sufficient quantities of additives as approved in the H2S 

Contingency Plan are available for the: 

1. Control of H2S (scavengers). 

2. Control of well-control fluid pH. 

3. Control for corrosion of equipment. 

IF NONCOMPLIANCE EXISTS:

Issue a facility shut-in (S) INC if sufficient quantities of additives are not available to control: 

1. H2S. 

2. Well-control fluid pH. 

3. Corrosion of equipment. 

INSPECTION FORM:

Enter one item checked per facility. 

H-148 WHEN 

H2S IS DETECTED, IS DRILLING SUSPENDED UNTIL SCAVENGER IS CIRCULATED 

THROUGHOUT THE SYSTEM? 

Authority: 490(m)(4)(i) 

Enforcement Action: S 

INSPECTION PROCEDURE: 

If present on the facility during the detection of H2S, observe to see if drilling is suspended until 

scavenger is 

circulated throughout system. 

IF NONCOMPLIANCE EXISTS: 

Issue a facility shut-in (S) INC if drilling is not suspended and scavenger is not circulated throughout 

the system. 

INSPECTION FORM: 

Enter one item checked per facility. 

H-149

IS THE pH OF WATER-BASED WELL-CONTROL FLUIDS MAINTAINED AT A MINIMUM OF 

10.0? 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 102 May 2011 

Authority: 490(m)(4)(ii) 

Enforcement Action: S 

INSPECTION PROCEDURE: 

Check the Shell’s records to verify that the pH of water-based well-control fluids is maintained at a 

minimum of 10.0. 

IF NONCOMPLIANCE EXISTS: 

Issue a facility shut-in (S) INC if the pH of well-control fluids is not maintained at a minimum of 10.0. 

INSPECTION FORM: 

Enter one item checked per facility. 

H-150 

ARE WELL-CONTROL FLUIDS CONTAINING H2S DEGASSED AT THE OPTIMUM 

LOCATION FOR THE PARTICULAR FACILITY AND ARE THE GASSES REMOVED BURNED 

IN A CLOSED FLARE SYSTEM?

Authority: 490(m)(5) 

Enforcement Action: S 

INSPECTION PROCEDURE: 

1. Review H2S Contingency Plan to ascertain optimum location for degasser. 

2. Visually inspect the facility to confirm the presence of the degasser and that it is operative. 

3. Visually inspect the flare system to verify that it is a closed system. 

IF NONCOMPLIANCE EXISTS:

Issue a facility shut-in (S) INC if the degasser is not operative or if flare system is not a closed 

system. 

INSPECTION FORM:

Enter one item checked for each flare system inspected. 

H-151

IS A SAFETY MEETING CONDUCTED FOR ALL PERSONNEL WHO WILL BE ON THE 

FACILITY PRIOR TO WELL TESTING? 

Authority: 490(o)(1) 

Enforcement Action: C 

INSPECTION PROCEDURE:

Check Shell's records to verify that a safety meeting was held for all personnel prior to well testing 

operations. 

IF NONCOMPLIANCE EXISTS:

Issue a component shut-in (C) INC for well testing operations if a safety meeting for all personnel 

was not conducted prior to commencing well testing. 

INSPECTION FORM:

Enter one item checked per facility. 

H-152

ARE ALL GASES PRODUCED DURING TESTING BURNED THROUGH A FLARE SYSTEM 

WHICH MEETS THE REQUIREMENTS OF 30 CFR 490(o)(3)? 

Authority: 490(o)(3) 

Enforcement Action: S 

INSPECTION PROCEDURE:
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 103 May 2011 

Visually inspect the well testing operation and equipment to verify that all gases produced during 

testing will be routed to the flare system and burned as prescribed by the requirements of 30 CFR 

490(o)(3). 

IF NONCOMPLIANCE EXISTS:

Issue a facility shut-in (S) INC if the gases produced during well testing are not routed into the flare 

system and burned as per the requirements of 30 CFR 490(o)(3). 

INSPECTION FORM:

Enter one item checked per facility. 

H-153

ARE FLARE LINE OUTLETS LOCATED ON THE DOWNWIND SIDE AND AS FAR FROM THE 

FACILITY AS IS FEASIBLE? 

Authority: 490(q)(6) 

Enforcement Action: S 

INSPECTION PROCEDURE:

Visually inspect the facility to verify that the flare line outlets are located: 

1. On the downwind side of the facility. 

2. As far from the facility as is feasible. 

IF NONCOMPLIANCE EXISTS:

Issue a facility shut-in (S) INC if the flare line outlets are not located as required. 

INSPECTION FORM:

Enter one item checked per facility. 

H-154

IS THE FLARE OUTLET EQUIPPED WITH AN AUTOMATIC IGNITION SYSTEM INCLUDING 

A PILOT-LIGHT GAS SOURCE OR AN EQUIVALENT SYSTEM? 

Authority: 490(q)(6) 

Enforcement Action: S 

INSPECTION PROCEDURE:

Visually inspect the flare system to verify that it is equipped with an automatic ignition system 

including a pilot-light gas source or an equivalent system. 

IF NONCOMPLIANCE EXISTS:

Issue a facility shut-in (S) INC if the flare system is not equipped with an automatic ignition system 

including a pilot-light gas source or an equivalent system. 

INSPECTION FORM:

Enter one item checked per facility. 

H-155

IS AN ALTERNATE METHOD AVAILABLE FOR IGNITING THE FLARE? 

Authority: 490(q)(6) 

Enforcement Action: W 

INSPECTION PROCEDURE:

Visually inspect the flare system to verify that an alternate method of ignition is provided. 

IF NONCOMPLIANCE EXISTS:

Issue a warning (W) INC if an alternate method of igniting the flare is not provided. 

INSPECTION FORM:

Enter one item checked per facility. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 104 May 2011 

H-156

ARE ALL VENTS USED FOR H2S PRODUCTION PROCESS EQUIPMENT, TANKS, RELIEF 

VALVES, BURST PLATES, AND SIMILAR DEVICES PIPED TO THE FLARE SYSTEM? 

Authority: 490(q)(6) 

Enforcement Action: C/S 

INSPECTION PROCEDURE:

Visually inspect the facility to verify that all vents are piped to the flare system used for H2S for: 

1. Production process equipment. 

2. Tanks. 

3. Relief valves. 

4. Burst plates. 

5. Similar devices. 

IF NONCOMPLIANCE EXISTS:

Issue a component shut-in (C) INC if certain components are not vented properly. 

Issue a facility shut-in (S) INC if all components on the facility are not vented properly. 

INSPECTION FORM:

Enter one item checked per component inspected. 

H-157

IS GAS CONTAINING H2S NOT USED FOR INSTRUMENT GAS, AND IF H2S IS BEING USED 

AS FUEL GAS, DOES THE SHELL HAVE APPROVAL FROM THE DISTRICT SUPERVISOR? 

Authority: 490(q)(9) 

Enforcement Action: S 

INSPECTION PROCEDURE:

1. Check Shell's records and inspect all instruments for any indication that gas containing H2S may 

be being used for instruments. 

2. Check Shell's records and all combustion devices for indications that gas containing H2S may be 

used for fuel. The District Supervisor may approve the use of gas containing H2S for fuel. If no 

approval has been given and indications are present, Shell must prove that gas used for fuel does 

not contain H2S. 

IF NONCOMPLIANCE EXISTS:

Issue a facility shut-in (S) INC if gas containing H2S is used for instruments or if gas containing H2S 

is used for fuel without the prior approval of the District Supervisor. 

INSPECTION FORM:

Enter one item checked for each facility. 

H-158

HAS THE DISTRICT SUPERVISOR BEEN NOTIFIED IF PRODUCED WATER IS DISPOSED OF 

BY MEANS OTHER THAN SUBSURFACE INJECTION? 

Authority: 490(q)(12) 

Enforcement Action: S 

INSPECTION PROCEDURE:

Inspect the production process system to verify that produced water to be disposed of by means 

other than subsurface injection is treated for removal of H2S. 

IF NONCOMPLIANCE EXISTS:

Issue a facility shut-in (S) INC if the produced water to be disposed of by means other than 

subsurface injection is not treated for removal of H2S and does not have approval by the District 

Supervisor. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 105 May 2011 

INSPECTION FORM:

Enter one item checked per facility. 

H-159

ARE H2S LEVELS CONTINUOUSLY MONITORED IN THE WORK AREAS DURING 

DRILLING, WELL-COMPLETION, AND WELL-WORKOVER OPERATIONS? 

Authority: 490(j)(4)(i) 

Enforcement Action: W/S 

490(j)(4)(ii) 

490(j)(4)(iii) 

490(j)(4)(iv) 

490(j)(4)(v) 

INSPECTION PROCEDURE:

1. Check Shell's records to verify that H2S levels were monitored in the work area when: 

A. Pulling a wet string of drill pipe; 

B. Pulling a workover string; 

C. Circulating bottoms-up after a drilling break; 

D. Cementing; 

E. Logging; and 

F. Circulating to condition mud or other well-control fluids. 

2. If present during such operations, verify that the required monitoring is being conducted. 

IF NONCOMPLIANCE EXISTS:

Issue a warning (W) INC if records indicate that monitoring was not conducted during such 

operations. 

Issue a facility shut-in (S) INC if such monitoring is not being conducted when present during such 

operations. 

INSPECTION FORM:

Enter one item checked per facility. 

H-160

WHEN CONDUCTING CORING OPERATIONS, IS PROTECTIVE BREATHING EQUIPMENT 

WORN BY ALL PERSONNEL IN THE WORK AREA AT LEAST 10 STANDS IN ADVANCE OF 

RETRIEVING THE CORE BARREL? 

Authority: 490(q)(1) 

Enforcement Action: W/S 

INSPECTION PROCEDURE:

1. Check Shell's records to verify that protective breathing equipment was worn by personnel in the 

work area at least 10 stands in advance of retrieving the core barrel during conventional coring 

operations. 

2. If present during such operations, verify that protective breathing equipment is worn by personnel 

in the work area at least 10 stands in advance of retrieving the core barrel during conventional 

coring operations. 

IF NONCOMPLIANCE EXISTS:

Issue a warning (W) INC if records indicate that protective breathing equipment was not worn by 

personnel in the work area at least 10 stands in advance of retrieving the core barrel during 

conventional coring operations. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 106 May 2011 

Issue a facility shut-in (S) INC if protective breathing equipment is not worn by personnel in the work 

area at least 10 stands in advance of retrieving the core barrel during conventional coring 

operations, if present during such operations. 

INSPECTION FORMS:

Enter one item checked per facility. 

H-161

ARE ALL CORES TO BE TRANSPORTED SEALED AND MARKED FOR THE PRESENCE OF 

H2S? 

Authority: 490(q)(1) 

Enforcement Action: W/S 

INSPECTION PROCEDURE:

1. Check Shell's records to verify that all cores to be transported were sealed and marked for the 

presence of H2S. 

2. If present on the facility, inspect all cores to verify that they have been sealed and marked for the 

presence of H2S. 

IF NONCOMPLIANCE EXISTS:

Issue a warning (W) INC if records indicate that cores were not sealed and marked for the presence 

of H2S. 

Issue a facility shut-in (S) INC if cores are not sealed and marked for the presence of H2S if present 

on the facility during inspection. 

INSPECTION FORM:

Enter one item checked per facility. 

H-162

IS WELL-CONTROL FLUID IN USE FOR LOGGING OPERATIONS CONDITIONED AND 

TREATED TO MINIMIZE THE EFFECT OF H2S ON THE LOGGING EQUIPMENT? 

Authority: 490(q)(2) 

Enforcement Action: W/S 

INSPECTION PROCEDURE:

1. Inspect Shell's records to verify that well-control fluids in use during logging operations were 

conditioned and treated to minimize the effect of H2S on the logging equipment. 

2. If present during logging operations, observe well-control fluid handling operations and check 

records to verify that the well-control fluids have been conditioned and treated to minimize the effect 

of H2S on the logging equipment. 

IF NONCOMPLIANCE EXISTS:

Issue a warning (W) INC if records indicate that the well-control fluids in use during logging 

operations were not conditioned and treated to minimize the effect of H2S on the logging equipment. 

Issue a facility shut-in (S) INC if present during logging operations and the well-control fluids have 

not been conditioned and treated to minimize the effect of H2S on the logging equipment. 

INSPECTION FORM:

Enter one item checked per facility. 

H-163

DURING STRIPPING OPERATIONS, ARE DISPLACED WELL-CONTROL FLUID RETURNS 

MONITORED BY PERSONNEL? 

Authority: 490(q)(3) 

Enforcement Action: W/S 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 107 May 2011 

INSPECTION PROCEDURE:

1. Check Shell's records to verify that well-control fluid returns were monitored by personnel during 

stripping operations. 

2. If present during stripping operations, observe well-control fluid returns for the presence of 

monitoring 

personnel. 

IF NONCOMPLIANCE EXISTS:

Issue a warning (W) INC if records indicate that well-control fluid returns were not monitored by 

personnel during stripping operations. 

Issue a facility shut-in (S) INC if present during stripping operations and well-control fluid returns are 

not monitored by personnel. 

INSPECTION FORM:

Enter one item checked per facility. 

H-164

DURING STRIPPING OPERATIONS, IS PROTECTIVE BREATHING EQUIPMENT WORN BY 

PERSONNEL IN THE WORK AREA WHEN THE ATMOSPHERIC CONCENTRATION OF H2S 

REACHES OR EXCEEDS 20 PPM OR IF THE WELL IS UNDER PRESSURE? 

Authority: 490(q)(3) 

Enforcement Action: W/S 

INSPECTION PROCEDURE:

1. Check Shell's records to verify that protective breathing equipment was worn by personnel in the 

work area during stripping operations when the concentration of H2S reached or exceeded 20 ppm, 

or if the well was under pressure. 

2. If present during stripping operations and the concentration of H2S equals or exceeds 20 ppm, or 

if the well is under pressure, observe the work area to verify that personnel are wearing protective 

breathing equipment. 

IF NONCOMPLIANCE EXISTS:

Issue a warning (W) INC if records indicate that personnel did not wear protective breathing 

equipment during stripping operations when the concentration of H2S reached or exceeded 20 ppm, 

or if the well was under pressure. 

Issue a facility shut-in (S) INC if present during stripping operations and protective breathing 

equipment is not worn by personnel in the work area if the concentration of H2S reaches or exceeds 

20 ppm, or if the well is under pressure. 

INSPECTION FORM:

Enter one item checked per facility. 

H-165

IS PROTECTIVE BREATHING EQUIPMENT WORN BY PERSONNEL IN THE WORK AREA 

DURING BOTTOMS-UP WHEN CIRCULATING OUT A KICK AND DURING EXTENDED KILL 

OPERATIONS? 

Authority: 490(q)(4) 

Enforcement Action: W/S 

INSPECTION PROCEDURE:

1. Check Shell's records to verify that protective breathing equipment was worn by personnel in the 

work area during bottoms-up when circulating out a kick and during extended kill operations. 

2. If present during bottoms-up when circulating out a kick and during extended kill operations, 

observe the 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 108 May 2011 

work area to verify that personnel are wearing protective breathing equipment. 

IF NONCOMPLIANCE EXISTS:

Issue a warning (W) INC if records indicate that personnel did not wear protective breathing 

equipment during bottoms-up when circulating out a kick and during extended kill operations. 

Issue a facility shut-in (S) INC for the facility if present during bottoms-up when circulating out a kick 

and during extended kill operations if personnel in the work area are not wearing protective 

breathing equipment. 

INSPECTION FORM:

Enter one item checked per facility. 

H-166

IS AN EFFECTIVE MEANS OF MONITORING AND CONTROLLING CORROSION CAUSED BY 

ACID GASES USED IN BOTH THE DOWNHOLE AND SURFACE PORTIONS OF A 

PRODUCTION SYSTEM? 

Authority: 490(q)(7) 

Enforcement Action: S 

INSPECTION PROCEDURE:

Check Shell's records and observe production system for indications of corrosion monitoring and 

control equipment. The Shell must prove that such means for monitoring and controlling corrosion 

exist. 

IF NONCOMPLIANCE EXISTS:

Issue a facility shut-in (S) INC if records and observations indicate that an effective means of 

monitoring and controlling corrosion in both the downhole and surface portions of the production 

system does not exist. 

INSPECTION FORM: 

Enter one item checked per facility. 

H-167

ARE LUBRICATORS WHICH MAY BE EXPOSED TO FLUIDS CONTAINING H2S MADE OF 

H2S-RESISTANT MATERIALS? 

Authority: 490(q)(8) 

Enforcement Action: W/S 

INSPECTION PROCEDURE:

1. Check Shell's records to verify that lubricators exposed to fluids containing H2S were made of H2S 

resistant materials. 

2. If present when lubricators are installed, visually inspect the lubricator for make and model and 

verify with records that they are made of H2S resistant material. 

IF NONCOMPLIANCE EXISTS:

Issue a warning (W) INC if Shell’s records indicate that lubricators exposed to fluids containing H2S 

were not made of H2S resistant material. 

Issue a facility shut-in (S) INC if the lubricators which may be exposed to fluids containing H2S and 

in use during the inspection are not made of H2S resistant materials. 

INSPECTION FORM:

Enter one item checked for each lubricator. 

H-168

ARE METALS USED FOR SENSING LINES AND SAFETY-CONTROL DEVICES WHICH ARE 

EXPOSED TO H2S BEARING FLUIDS CONSTRUCTED OF H2S CORROSION RESISTANT 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 109 May 2011 

MATERIALS OR COATED WITH APPROPRIATE MATERIALS SO AS TO RESIST 

CORROSION? 

Authority: 490(q)(10) 

Enforcement Action: W/S 

INSPECTION PROCEDURE:

1. Check Shell's records to verify that metals used in sensing lines and safety-control devices which 

were exposed to H2S bearing fluids were constructed with H2S corrosion resistant materials or 

coated with appropriate materials so as to resist corrosion. 

2. If present on the facility during operations in a known H2S zone, verify that the metals and safetycontrol devices are properly constructed or coated. 

IF NONCOMPLIANCE EXISTS:

Issue a warning (W) INC if the metals were not properly constructed or coated so as to resist H2S 

corrosion. 

Issue a facility shut-in (S) INC if present on the facility during operations in a known H2S bearing 

zone and the metals and safety-control devices are not properly constructed or coated. 

INSPECTION FORM:

Enter one item checked per facility. . 

H-169

ARE ALL SEALS WHICH MAY BE EXPOSED TO FLUIDS CONTAINING H2S MADE OF H2SRESISTANT MATERIAL? 

Authority: 490(q)(11)

Enforcement Action: W/S

INSPECTION PROCEDURE:

1. Inspect records to verify that all seals, which were in service while operating in a known H2S zone 

and which may have been exposed to fluids containing H2S, were made of H2S-resistant material. 

2. If present while operations are conducted in a known H2S zone, verify that all seals, which may be 

exposed to fluids containing H2S, are made of H2S-resistant material by visual observation and 

records checks. 

IF NONCOMPLIANCE EXISTS:

Issue a warning (W) INC if records indicate that seals, which may have been exposed to fluids 

containing H2S, were not made of H2S-resistant material. 

Issue a facility shut-in (S) INC if seals which may be exposed to fluids containing H2S are not 

constructed of H2S resistant material, if witnessed during operations in a known H2S zone. 

INSPECTION FORM:

Enter one item checked per facility. 

H-170 

DO TRAINED EMPLOYEES OR CONTRACTORS TRANSFERRED FROM ANOTHER 

FACILITY RECEIVE A SUPPLEMENTAL BRIEFING ON H2S EQUIPMENT AND PROCEDURES 

BEFORE BEGINNING DUTY? 

Authority: 490(g)(3)(i) 

Enforcement Action: W 

INSPECTION PROCEDURE: 

Verify that all Shell and contract personnel from other facilities have received a supplemental 

briefing on H2S equipment and procedures for this facility. 

IF NONCOMPLIANCE EXISTS: 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 110 May 2011 

Issue a warning (W) INC if any Shell or contract personnel have not received a supplemental 

briefing for this facility. 

INSPECTION FORM: 

Enter one item checked per facility. 

H-171

DO VISITORS WHO REMAIN AT THE FACILITY FOR MORE THAN 24 HOURS RECEIVE THE 

TRAINING REQUIRED FOR EMPLOYEES AND CONTRACTORS? 

Authority: 490(g)(3)(ii) 

Enforcement Action: W 

INSPECTION PROCEDURE: 

Verify that all visitors that will be on the facility for more than 24 hours have received the same 

training as required for the Shells and contractors. 

IF NONCOMPLIANCE EXISTS: 

Issue a warning (W) INC if any visitors are on the facility more than 24 hours without receiving the 

same required training as the Shells and contractors. 

INSPECTION FORM: 

Enter one item checked per facility. 

H-172 

DO VISITORS WHO WILL DEPART THE FACILITY WITHIN 24 HOURS RECEIVE A 

BRIEFING ON H2S PROCEDURES? 

Authority: 490(g)(3)(iii) 

Enforcement Action: W 

INSPECTION PROCEDURES: 

Verify that all visitors departing the facility within 24 hours have received a briefing on H2S 

procedures. 

IF NONCOMPLIANCE EXISTS: 

Issue a warning (W) INC if records show any visitors departing the facility within 24 hours have not 

received the required briefing. 

INSPECTION FORM: 

Enter one item checked per facility. 

H-173 

ARE RECORDS OF ATTENDANCE IN DRILLS FOR DRILLING, WELL-COMPLETION, AND 

WELL-WORKOVER OPERATIONS MAINTAINED AT THE FACILITY UNTIL OPERATIONS 

ARE COMPLETED? 

Authority: 490(h)(2)(i) 

Enforcement Action: W

INSPECTION PROCEDURE: 

Verify that drill attendance records for drilling, well-completion, and well-workover operations are 

maintained on the facility until operations are completed. 

IF NONCOMPLIANCE EXISTS: 

Issue a warning (W) INC if records for drills for drilling, well-completion, and well-workover 

operations are not being maintained at the facility. 

INSPECTION FORM: 

Enter one item checked per facility. 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 111 May 2011 

H-174 

ARE RECORDS OF ATTENDANCE IN DRILLS FOR PRODUCTION OPERATIONS 

MAINTAINED AT THE FACILITY OR THE NEAREST FIELD OFFICE FOR 1 YEAR? 

Authority: 490(h)(2)(ii) 

Enforcement Action: W 

INSPECTION PROCEDURE: 

Verify that records of attendance in drills for production operations are maintained on the facility or 

the nearest field office for 1 year. 

IF NONCOMPLIANCE EXISTS: 

Issue a warning (W) INC if records of attendance in drills for production operations are not 

maintained at the facility or nearest field office for 1 year. 

INSPECTION FORM: 

Enter one item checked per facility. 

H-175 

ARE PORTABLE OR STRATEGICALLY PLACED FIXED S02 DEVICES CAPABLE OF 

DETECTING A MINIMUM OF 2 PPM OF SO2 AVAILABLE OR IN USE AT THE FACILITY? 

Authority: 490(j)(11)(i) 

Enforcement Action: W/S 

INSPECTION PROCEDURE: 

1. Verify that portable SO2 devices are available on the facility. 

2. Verify that strategically placed fixed SO2 devices in use on the facility are capable of detecting a 

minimum of 2 ppm of SO2

IF NONCOMPLIANCE EXISTS: 

1. Issue a warning (W) INC if portable SO2 devices capable of detecting a minimum of 2 ppm of SO2

are not available and flaring is not ongoing. 

2. Issue a facility shut-in (S) INC if strategically placed fixed SO2 devices are not available on the 

facility or not capable of detecting 2 ppm of SO2 during flaring. 

INSPECTION FORM: 

Enter one item checked for each device inspected. 

H-176 ARE PORTABLE OR FIXED SO2 ELECTRONIC SENSING DEVICES CALIBRATED 

EVERY 

3 MONTHS? 

Authority: 490(j)(11)(iv) 

Enforcement Action: W/S 

INSPECTION PROCEDURE: 

Verify that portable or fixed SO2 electronic sensing devices have been calibrated every 3 months. 

IF NONCOMPLIANCE EXISTS: 

Issue a warning (W) INC if records indicate a period was greater than 3 months between 

calibrations but subsequent calibrations were conducted within the required time period. 

Issue a facility shut-in (S) INC if inspection shows the last calibration occurred more than 3 months 

ago. 

INSPECTION FORM: 

Enter one item checked per facility. 

H-177 

ARE SPECTACLE KITS AVAILABLE FOR RESPIRATORS AS NEEDED? 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 112 May 2011 

Authority: 490(j)(13)(iv) 

Enforcement Action: W 

INSPECTION PROCEDURE: 

Inspect all respirators that require spectacle kits for specified personnel with vision problems. 

IF NONCOMPLIANCE EXISTS: 

Issue a warning (W) INC when spectacle kits in respirators are not issued to specified personnel. 

INSPECTION FORM: 

Enter one item checked per respirator inspected. 

H-178 

ARE COMPRESSORS EXCEEDING 50 HP COVERED BY AT LEAST TWO H2S SENSORS 

LOCATED WITHIN 10 FEET OF THE COMPRESSOR? 

Authority: 490(j)(5)(iv) 

Enforcement Action: C 

INSPECTION PROCEDURE: 

Verify that at least two H2S sensors are located within 10 feet of each compressor that exceeds 50 

hp. 

IF NONCOMPLIANCE EXISTS: 

Issue a component shut-in (C) INC if there are not at least two sensors located within 10 feet of any 

compressor that exceeds 50 hp. 

INSPECTION FORM: 

Enter one item checked per inspection. 

H-179 

WHEN DRILLING, ARE FUNCTIONAL TESTS OF H2S DETECTORS INITIATED BEFORE THE 

BIT IS 1,500 FEET (VERTICALLY) ABOVE THE POTENTIAL H2S ZONE? 

Authority: 490(j)(7)(i) 

Enforcement Action: W 

INSPECTION PROCEDURE: 

Inspect the driller’s log to verify that functional tests are initiated before the bit is 1,500 feet 

(vertically) above the potential H2S zone. 

IF NONCOMPLIANCE EXISTS: 

Issue a warning (W) INC if functional tests are not initiated before the bit is 1,500 feet (vertically) 

above any potential H2S zone. 

INSPECTION FORM: 

Enter one item checked per inspection. 

H-180 

WHEN CONDUCTING PRODUCTION OPERATIONS, ARE ALL H2S DETECTORS TESTED AT 

LEAST EVERY 14 DAYS? 

Authority: 490(j)(7)(ii) 

Enforcement Action: C 

INSPECTION PROCEDURE: 

Verify that all H2S detectors are being tested at least every 14 days. 

IF NONCOMPLIANCE EXISTS: 

Issue a component shut-in (C) INC if records indicate that any H2S detector is not being tested at 

least every 14 days. 

INSPECTION FORM: 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 113 May 2011 

Enter one item checked per facility. 

H-181

IN AREAS CLASSIFIED AS H2S PRESENT, ARE ALL H2S DETECTORS TESTED ONCE EVERY 

24 HOURS WHEN CONDUCTING DRILLING OPERATIONS, DRILL STEM TESTING, WELL 

TESTING, WELL COMPLETION OPERATIONS, OR WORKOVER OPERATIONS? 

Authority: 490(j)(7)(i)

Enforcement Action: W/S 

INSPECTION PROCEDURE: 

Verify that all H2S detectors are being tested once every 24 hours. 

IF NONCOMPLIANCE EXISTS: 

Issue a warning (W) INC if each H2S detector is not tested within the 24-hour time period, but 

subsequent tests were conducted as required. 

Issue a facility shut-in (S) INC if each H2S detector is not tested within the 24-hour time period and 

subsequent tests were not conducted. 

INSPECTION FORM: 

Enter one item checked per facility. 

 
Hydrogen Sulfide Contingency Plan Chukchi Sea, Alaska 

Shell Gulf of Mexico Inc. 114 May 2011 

SECTION D-3 

29 CFR - CHAPTER XVII - PART 1910 

THIS DATA CURRENT AS OF THE FEDERAL REGISTER DATED APRIL 25, 2003

§134. Respiratory protection 

This section applies to General Industry (part 1910), Shipyards (part 1915), Marine Terminals (part 

1917), Longshoring (part 1918), and Construction (part 1926). 

(a) Permissible practice. (1) In the control of those occupational diseases caused by breathing air 

contaminated with harmful dusts, fogs, fumes, mists, gases, smokes, sprays, or vapors, the primary 

objective shall be to prevent atmospheric contamination. This shall be accomplished as far as 

feasible by accepted engineering control measures (for example, enclosure or confinement of the 

operation, general and local ventilation, and substitution of less toxic materials). When effective 

engineering controls are not feasible, or while they are being instituted, appropriate respirators shall 

be used pursuant to this section. 

 (2) Respirators shall be provided by the employer when such equipment is necessary to 

protect the health of the employee. The employer shall provide the respirators which are 

applicable and suitable for the purpose intended. The employer shall be responsible for the 

establishment and maintenance of a respiratory protection program which shall include the 

requirements outlined in paragraph (c) of this section. 

(b) Definitions. The following definitions are important terms used in the respiratory protection 

standard in this section. 

Air-purifying respirator means a respirator with an air-purifying filter, cartridge, or canister that 

removes specific air contaminants by passing ambient air through the air-purifying element. 

Assigned protection factor (APF) [Reserved] 

Atmosphere-supplying respirator means a respirator that supplies the respirator user with breathing 

air from a source independent of the ambient atmosphere, and includes supplied-air respirators 

(SARs) and self-contained breathing apparatus (SCBA) units. 

Canister or cartridge means a container with a filter, sorbent, or catalyst, or combination of these 

items, which removes specific contaminants from the air passed through the container. 

Demand respirator means an atmosphere-supplying respirator that admits breathing air to the 

facepiece only when a negative pressure is created inside the facepiece by inhalation. 

Emergency situation means any occurrence such as, but not limited to, equipment failure, rupture of 

containers, or failure of control equipment that may or does result in an uncontrolled significant 

release of an airborne contaminant. 

Employee exposure means exposure to a concentration of an airborne contaminant that would 

occur if the employee were not using respiratory protection. 
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End-of-service-life indicator (ESLI) means a system that warns the respirator user of the approach 

of the end of adequate respiratory protection, for example, that the sorbent is approaching 

saturation or is no longer effective. 

Escape-only respirator means a respirator intended to be used only for emergency exit. 

Filter or air purifying element means a component used in respirators to remove solid or liquid 

aerosols from the inspired air. 

Filtering facepiece (dust mask) means a negative pressure particulate respirator with a filter as an 

integral part of the facepiece or with the entire facepiece composed of the filtering medium. 

Fit factor means a quantitative estimate of the fit of a particular respirator to a specific individual, and 

typically estimates the ratio of the concentration of a substance in ambient air to its concentration 

inside the respirator when worn. 

Fit test means the use of a protocol to qualitatively or quantitatively evaluate the fit of a respirator on 

an individual. (See also Qualitative fit test QLFT and Quantitative fit test QNFT.) 

Helmet means a rigid respiratory inlet covering that also provides head protection against impact 

and penetration. 

High efficiency particulate air (HEPA) filter means a filter that is at least 99.97% efficient in removing 

monodisperse particles of 0.3 micrometers in diameter. The equivalent NIOSH 42 CFR 84 

particulate filters are the N100, R100, and P100 filters. 

Hood means a respiratory inlet covering that completely covers the head and neck and may also 

cover portions of the shoulders and torso. 

Immediately dangerous to life or health (IDLH) means an atmosphere that poses an immediate 

threat to life, would cause irreversible adverse health effects, or would impair an individual's ability to 

escape from a dangerous atmosphere. 

Interior structural firefighting means the physical activity of fire suppression, rescue or both, inside of 

buildings or enclosed structures which are involved in a fire situation beyond the incipient stage. 

(See 29 CFR 1910.155) 

Loose-fitting facepiece means a respiratory inlet covering that is designed to form a partial seal with 

the face. 

Maximum use concentration (MUC) [Reserved]. 

Negative pressure respirator (tight fitting) means a respirator in which the air pressure inside the 

facepiece is negative during inhalation with respect to the ambient air pressure outside the 

respirator. 
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Oxygen deficient atmosphere means an atmosphere with an oxygen content below 19.5% by 

volume. 

Physician or other licensed health care professional (PLHCP) means an individual whose legally 

permitted scope of practice (i.e., license, registration, or certification) allows him or her to 

independently provide, or be delegated the responsibility to provide, some or all of the health care 

services required by paragraph (e) of this section. 

Positive pressure respirator means a respirator in which the pressure inside the respiratory inlet 

covering exceeds the ambient air pressure outside the respirator. 

Powered air-purifying respirator (PAPR) means an air-purifying respirator that uses a blower to force 

the ambient air through air-purifying elements to the inlet covering. 

Pressure demand respirator means a positive pressure atmosphere-supplying respirator that admits 

breathing air to the facepiece when the positive pressure is reduced inside the facepiece by 

inhalation. 

Qualitative fit test (QLFT) means a pass/fail fit test to assess the adequacy of respirator fit that relies 

on the individual's response to the test agent. 

Quantitative fit test (QNFT) means an assessment of the adequacy of respirator fit by numerically 

measuring the amount of leakage into the respirator. 

Respiratory inlet covering means that portion of a respirator that forms the protective barrier 

between the user's respiratory tract and an air-purifying device or breathing air source, or both. It 

may be a facepiece, helmet, hood, suit, or a mouthpiece respirator with nose clamp. 

Self-contained breathing apparatus (SCBA) means an atmosphere-supplying respirator for which 

the breathing air source is designed to be carried by the user. 

Service life means the period of time that a respirator, filter or sorbent, or other respiratory 

equipment provides adequate protection to the wearer. 

Supplied-air respirator (SAR) or airline respirator means an atmosphere-supplying respirator for 

which the source of breathing air is not designed to be carried by the user. 

This section means this respiratory protection standard. 

Tight-fitting facepiece means a respiratory inlet covering that forms a complete seal with the face. 

User seal check means an action conducted by the respirator user to determine if the respirator is 

properly seated to the face. 

(c) Respiratory protection program. This paragraph requires the employer to develop and implement 

a written respiratory protection program with required worksite-specific procedures and elements for 

required respirator use. The program must be administered by a suitably trained program 

administrator. In addition, certain program elements may be required for voluntary use to prevent 
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potential hazards associated with the use of the respirator. The Small Entity Compliance Guide 

contains criteria for the selection of a program administrator and a sample program that meets the 

requirements of this paragraph. Copies of the Small Entity Compliance Guide will be available on or 

about April 8, 1998 from the Occupational Safety and Health Administration's Office of Publications, 

Room N 3101, 200 Constitution Avenue, NW, Washington, DC, 20210 (202-219-4667). 

 (1) In any workplace where respirators are necessary to protect the health of the employee 

or whenever respirators are required by the employer, the employer shall establish and 

implement a written respiratory protection program with worksite-specific procedures. The 

program shall be updated as necessary to reflect those changes in workplace conditions that 

affect respirator use. The employer shall include in the program the following provisions of 

this section, as applicable: 

 (i) Procedures for selecting respirators for use in the workplace; 

 (ii) Medical evaluations of employees required to use respirators; 

 (iii) Fit testing procedures for tight-fitting respirators; 

 (iv) Procedures for proper use of respirators in routine and reasonably foreseeable 

emergency situations; 

 (v) Procedures and schedules for cleaning, disinfecting, storing, inspecting, repairing, 

discarding, and otherwise maintaining respirators; 

 (vi) Procedures to ensure adequate air quality, quantity, and flow of breathing air for 

atmosphere-supplying respirators; 

 (vii) Training of employees in the respiratory hazards to which they are potentially 

exposed during routine and emergency situations; 

 (viii) Training of employees in the proper use of respirators, including putting on and 

removing them, any limitations on their use, and their maintenance; and 

 (ix) Procedures for regularly evaluating the effectiveness of the program. 

 (2) Where respirator use is not required: 

 (i) An employer may provide respirators at the request of employees or permit 

employees to use their own respirators, if the employer determines that such respirator 

use will not in itself create a hazard. If the employer determines that any voluntary 

respirator use is permissible, the employer shall provide the respirator users with the 

information contained in Appendix D to this section ("Information for Employees Using 

Respirators When Not Required Under the Standard"); and 

 (ii) In addition, the employer must establish and implement those elements of a written 

respiratory protection program necessary to ensure that any employee using a 

respirator voluntarily is medically able to use that respirator, and that the respirator is 
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cleaned, stored, and maintained so that its use does not present a health hazard to the 

user. Exception: Employers are not required to include in a written respiratory 

protection program those employees whose only use of respirators involves the 

voluntary use of filtering facepieces (dust masks). 

 (3) The employer shall designate a program administrator who is qualified by appropriate 

training or experience that is commensurate with the complexity of the program to administer 

or oversee the respiratory protection program and conduct the required evaluations of 

program effectiveness. 

 (4) The employer shall provide respirators, training, and medical evaluations at no cost to the 

employee. 

(d) Selection of respirators. This paragraph requires the employer to evaluate respiratory hazard(s) 

in the workplace, identify relevant workplace and user factors, and base respirator selection on 

these factors. The paragraph also specifies appropriately protective respirators for use in IDLH 

atmospheres, and limits the selection and use of air-purifying respirators. 

 (1) General requirements. (i) The employer shall select and provide an appropriate 

respirator based on the respiratory hazard(s) to which the worker is exposed and workplace 

and user factors that affect respirator performance and reliability. 

 (ii) The employer shall select a NIOSH-certified respirator. The respirator shall be 

used in compliance with the conditions of its certification. 

 (iii) The employer shall identify and evaluate the respiratory hazard(s) in the 

workplace; this evaluation shall include a reasonable estimate of employee exposures 

to respiratory hazard(s) and an identification of the contaminant's chemical state and 

physical form. Where the employer cannot identify or reasonably estimate the 

employee exposure, the employer shall consider the atmosphere to be IDLH. 

 (iv) The employer shall select respirators from a sufficient number of respirator 

models and sizes so that the respirator is acceptable to, and correctly fits, the user. 

 (2) Respirators for IDLH atmospheres. (i) The employer shall provide the following 

respirators for employee use in IDLH atmospheres: 

 (A) A full facepiece pressure demand SCBA certified by NIOSH for a minimum 

service life of thirty minutes, or 

 (B) A combination full facepiece pressure demand supplied-air respirator (SAR) 

with auxiliary self-contained air supply. 

 (ii) Respirators provided only for escape from IDLH atmospheres shall be NIOSHcertified for escape from the atmosphere in which they will be used. 

 (iii) All oxygen-deficient atmospheres shall be considered IDLH. Exception: If the 

employer demonstrates that, under all foreseeable conditions, the oxygen 
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concentration can be maintained within the ranges specified in Table II of this section 

(i.e., for the altitudes set out in the table), then any atmosphere-supplying respirator 

may be used. 

 (3) Respirators for atmospheres that are not IDLH. (i) The employer shall provide a 

respirator that is adequate to protect the health of the employee and ensure compliance with 

all other OSHA statutory and regulatory requirements, under routine and reasonably 

foreseeable emergency situations. 

 (A) Assigned Protection Factors (APFs) [Reserved] 

 (B) Maximum Use Concentration (MUC) [Reserved] 

 (ii) The respirator selected shall be appropriate for the chemical state and physical 

form of the contaminant. 

 (iii) For protection against gases and vapors, the employer shall provide: 

 (A) An atmosphere-supplying respirator, or 

 (B) An air-purifying respirator, provided that: 

 ( 1 ) The respirator is equipped with an end-of-service-life indicator 

(ESLI) certified by NIOSH for the contaminant; or 

 ( 2 ) If there is no ESLI appropriate for conditions in the employer's 

workplace, the employer implements a change schedule for canisters 

and cartridges that is based on objective information or data that will 

ensure that canisters and cartridges are changed before the end of their 

service life. The employer shall describe in the respirator program the 

information and data relied upon and the basis for the canister and 

cartridge change schedule and the basis for reliance on the data. 

 (iv) For protection against particulates, the employer shall provide: 

 (A) An atmosphere-supplying respirator; or 

 (B) An air-purifying respirator equipped with a filter certified by NIOSH under 30 

CFR part 11 as a high efficiency particulate air (HEPA) filter, or an air-purifying 

respirator equipped with a filter certified for particulates by NIOSH under 42 

CFR part 84; or 

 (C) For contaminants consisting primarily of particles with mass median 

aerodynamic diameters (MMAD) of at least 2 micrometers, an air-purifying 

respirator equipped with any filter certified for particulates by NIOSH. 

Table I_Assigned Protection Factors [Reserved] 
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Table II 

------------------------------------------------------------------------ 

Oxygen deficient Atmospheres (% O2) for Altitude (ft.) 

which the employer may rely on atmosphere-supplying 

respirators 

------------------------------------------------------------------------ 

Less than 3,001............................................ 16.0-19.5 

3,001-4,000................................................ 16.4-19.5 

4,001-5,000................................................ 17.1-19.5 

5,001-6,000................................................ 17.8-19.5 

6,001-7,000................................................ 18.5-19.5 

7,001-8,0001

............................................. 19.3-19.5. 

------------------------------------------------------------------------ 

1

Above 8,000 feet the exception does not apply. 

Oxygen-enriched breathing air must be supplied above 

14,000 feet. 

(e) Medical evaluation. Using a respirator may place a physiological burden on employees that 

varies with the type of respirator worn, the job and workplace conditions in which the respirator is 

used, and the medical status of the employee. Accordingly, this paragraph specifies the minimum 

requirements for medical evaluation that employers must implement to determine the employee's 

ability to use a respirator. 

 (1) General. The employer shall provide a medical evaluation to determine the employee's 

ability to use a respirator, before the employee is fit tested or required to use the respirator in 

the workplace. The employer may discontinue an employee's medical evaluations when the 

employee is no longer required to use a respirator. 

 (2) Medical evaluation procedures. (i) The employer shall identify a physician or other 

licensed health care professional (PLHCP) to perform medical evaluations using a medical 

questionnaire or an initial medical examination that obtains the same information as the 

medical questionnaire. 

 (ii) The medical evaluation shall obtain the information requested by the questionnaire 

in Sections 1 and 2, Part A of Appendix C of this section. 

 (3) Follow-up medical examination. (i) The employer shall ensure that a follow-up medical 

examination is provided for an employee who gives a positive response to any question 
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among questions 1 through 8 in Section 2, Part A of Appendix C or whose initial medical 

examination demonstrates the need for a follow-up medical examination. 

 (ii) The follow-up medical examination shall include any medical tests, consultations, 

or diagnostic procedures that the PLHCP deems necessary to make a final 

determination. 

 (4) Administration of the medical questionnaire and examinations. (i) The medical 

questionnaire and examinations shall be administered confidentially during the employee's 

normal working hours or at a time and place convenient to the employee. The medical 

questionnaire shall be administered in a manner that ensures that the employee understands 

its content. 

 (ii) The employer shall provide the employee with an opportunity to discuss the 

questionnaire and examination results with the PLHCP. 

 (5) Supplemental information for the PLHCP. (i) The following information must be provided 

to the PLHCP before the PLHCP makes a recommendation concerning an employee's ability 

to use a respirator: 

 (A) The type and weight of the respirator to be used by the employee; 

 (B) The duration and frequency of respirator use (including use for rescue and 

escape); 

 (C) The expected physical work effort; 

 (D) Additional protective clothing and equipment to be worn; and 

 (E) Temperature and humidity extremes that may be encountered. 

 (ii) Any supplemental information provided previously to the PLHCP regarding an 

employee need not be provided for a subsequent medical evaluation if the information 

and the PLHCP remain the same. 

 (iii) The employer shall provide the PLHCP with a copy of the written respiratory 

protection program and a copy of this section. 

 Note to paragraph 

(e)(5)(iii): When the employer replaces a PLHCP, the employer must ensure that the new PLHCP 

obtains this information, either by providing the documents directly to the PLHCP or having the 

documents transferred from the former PLHCP to the new PLHCP. However, OSHA does not 

expect employers to have employees medically reevaluated solely because a new PLHCP has been 

selected. 
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(6) Medical determination. In determining the employee's ability to use a respirator, the employer 

shall: 

 (i) Obtain a written recommendation regarding the employee's ability to use the respirator 

from the PLHCP. The recommendation shall provide only the following information: 

 (A) Any limitations on respirator use related to the medical condition of the employee, 

or relating to the workplace conditions in which the respirator will be used, including 

whether or not the employee is medically able to use the respirator; 

 (B) The need, if any, for follow-up medical evaluations; and 

 (C) A statement that the PLHCP has provided the employee with a copy of the 

PLHCP's written recommendation. 

 (ii) If the respirator is a negative pressure respirator and the PLHCP finds a medical 

condition that may place the employee's health at increased risk if the respirator is used, the 

employer shall provide a PAPR if the PLHCP's medical evaluation finds that the employee 

can use such a respirator; if a subsequent medical evaluation finds that the employee is 

medically able to use a negative pressure respirator, then the employer is no longer required 

to provide a PAPR. 

(7) Additional medical evaluations. At a minimum, the employer shall provide additional medical 

evaluations that comply with the requirements of this section if: 

 (i) An employee reports medical signs or symptoms that are related to ability to use a 

respirator; 

 (ii) A PLHCP, supervisor, or the respirator program administrator informs the employer that 

an employee needs to be reevaluated; 

 (iii) Information from the respiratory protection program, including observations made during 

fit testing and program evaluation, indicates a need for employee reevaluation; or 

 (iv) A change occurs in workplace conditions (e.g., physical work effort, protective clothing, 

temperature) that may result in a substantial increase in the physiological burden placed on 

an employee. 

(f) Fit testing. This paragraph requires that, before an employee may be required to use any 

respirator with a negative or positive pressure tight-fitting facepiece, the employee must be fit tested 

with the same make, model, style, and size of respirator that will be used. This paragraph specifies 

the kinds of fit tests allowed, the procedures for conducting them, and how the results of the fit tests 

must be used. 

 (1) The employer shall ensure that employees using a tight-fitting facepiece respirator pass 

an appropriate qualitative fit test (QLFT) or quantitative fit test (QNFT) as stated in this 

paragraph. 
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 (2) The employer shall ensure that an employee using a tight-fitting facepiece respirator is fit 

tested prior to initial use of the respirator, whenever a different respirator facepiece (size, 

style, model or make) is used, and at least annually thereafter. 

 (3) The employer shall conduct an additional fit test whenever the employee reports, or the 

employer, PLHCP, supervisor, or program administrator makes visual observations of, 

changes in the employee's physical condition that could affect respirator fit. Such conditions 

include, but are not limited to, facial scarring, dental changes, cosmetic surgery, or an 

obvious change in body weight. 

 (4) If after passing a QLFT or QNFT, the employee subsequently notifies the employer, 

program administrator, supervisor, or PLHCP that the fit of the respirator is unacceptable, the 

employee shall be given a reasonable opportunity to select a different respirator facepiece 

and to be retested. 

 (5) The fit test shall be administered using an OSHA-accepted QLFT or QNFT protocol. The 

OSHA-accepted QLFT and QNFT protocols and procedures are contained in Appendix A of 

this section. 

 (6) QLFT may only be used to fit test negative pressure air-purifying respirators that must 

achieve a fit factor of 100 or less. 

 (7) If the fit factor, as determined through an OSHA-accepted QNFT protocol, is equal to or 

greater than 100 for tight-fitting half facepieces, or equal to or greater than 500 for tight-fitting 

full facepieces, the QNFT has been passed with that respirator. 

 (8) Fit testing of tight-fitting atmosphere-supplying respirators and tight-fitting powered airpurifying respirators shall be accomplished by performing quantitative or qualitative fit testing 

in the negative pressure mode, regardless of the mode of operation (negative or positive 

pressure) that is used for respiratory protection. 

 (i) Qualitative fit testing of these respirators shall be accomplished by temporarily 

converting the respirator user's actual facepiece into a negative pressure respirator 

with appropriate filters, or by using an identical negative pressure air-purifying 

respirator facepiece with the same sealing surfaces as a surrogate for the 

atmosphere-supplying or powered air-purifying respirator facepiece. 

 (ii) Quantitative fit testing of these respirators shall be accomplished by modifying the 

facepiece to allow sampling inside the facepiece in the breathing zone of the user, 

midway between the nose and mouth. This requirement shall be accomplished by 

installing a permanent sampling probe onto a surrogate facepiece, or by using a 

sampling adapter designed to temporarily provide a means of sampling air from inside 

the facepiece. 

 (iii) Any modifications to the respirator facepiece for fit testing shall be completely 

removed, and the facepiece restored to NIOSH-approved configuration, before that 

facepiece can be used in the workplace. 
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(g) Use of respirators. This paragraph requires employers to establish and implement procedures for 

the proper use of respirators. These requirements include prohibiting conditions that may result in 

facepiece seal leakage, preventing employees from removing respirators in hazardous 

environments, taking actions to ensure continued effective respirator operation throughout the work 

shift, and establishing procedures for the use of respirators in IDLH atmospheres or in interior 

structural firefighting situations. 

 (1) Facepiece seal protection. (i) The employer shall not permit respirators with tight-fitting 

facepieces to be worn by employees who have: 

 (A) Facial hair that comes between the sealing surface of the facepiece and the 

face or that interferes with valve function; or 

 (B) Any condition that interferes with the face-to-facepiece seal or valve 

function. 

 (ii) If an employee wears corrective glasses or goggles or other personal protective 

equipment, the employer shall ensure that such equipment is worn in a manner that 

does not interfere with the seal of the facepiece to the face of the user. 

 (iii) For all tight-fitting respirators, the employer shall ensure that employees perform a 

user seal check each time they put on the respirator using the procedures in Appendix 

B-1 or procedures recommended by the respirator manufacturer that the employer 

demonstrates are as effective as those in Appendix B-1 of this section. 

 (2) Continuing respirator effectiveness. (i) Appropriate surveillance shall be maintained of 

work area conditions and degree of employee exposure or stress. When there is a change in 

work area conditions or degree of employee exposure or stress that may affect respirator 

effectiveness, the employer shall reevaluate the continued effectiveness of the respirator. 

 (ii) The employer shall ensure that employees leave the respirator use area: 

 (A) To wash their faces and respirator facepieces as necessary to prevent eye 

or skin irritation associated with respirator use; or 

 (B) If they detect vapor or gas breakthrough, changes in breathing resistance, 

or leakage of the facepiece; or 

 (C) To replace the respirator or the filter, cartridge, or canister elements. 

 (iii) If the employee detects vapor or gas breakthrough, changes in breathing 

resistance, or leakage of the facepiece, the employer must replace or repair the 

respirator before allowing the employee to return to the work area. 

 (3) Procedures for IDLH atmospheres. For all IDLH atmospheres, the employer shall 

ensure that: 
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 (i) One employee or, when needed, more than one employee is located outside the 

IDLH atmosphere; 

 (ii) Visual, voice, or signal line communication is maintained between the employee(s) 

in the IDLH atmosphere and the employee(s) located outside the IDLH atmosphere; 

 (iii) The employee(s) located outside the IDLH atmosphere are trained and equipped 

to provide effective emergency rescue; 

 (iv) The employer or designee is notified before the employee(s) located outside the 

IDLH atmosphere enter the IDLH atmosphere to provide emergency rescue; 

 (v) The employer or designee authorized to do so by the employer, once notified, 

provides necessary assistance appropriate to the situation; 

 (vi) Employee(s) located outside the IDLH atmospheres are equipped with: 

 (A) Pressure demand or other positive pressure SCBAs, or a pressure demand 

or other positive pressure supplied-air respirator with auxiliary SCBA; and either 

 (B) Appropriate retrieval equipment for removing the employee(s) who enter(s) 

these hazardous atmospheres where retrieval equipment would contribute to 

the rescue of the employee(s) and would not increase the overall risk resulting 

from entry; or 

 (C) Equivalent means for rescue where retrieval equipment is not required 

under paragraph (g)(3)(vi)(B). 

 (4) Procedures for interior structural firefighting. In addition to the requirements set forth 

under paragraph (g)(3), in interior structural fires, the employer shall ensure that: 

 (i) At least two employees enter the IDLH atmosphere and remain in visual or voice 

contact with one another at all times; 

 (ii) At least two employees are located outside the IDLH atmosphere; and 

 (iii) All employees engaged in interior structural firefighting use SCBAs. 

 Note 1 to paragraph 

(g): One of the two individuals located outside the IDLH atmosphere may be assigned to an 

additional role, such as incident commander in charge of the emergency or safety officer, so long as 

this individual is able to perform assistance or rescue activities without jeopardizing the safety or 

health of any firefighter working at the incident. 

Note 2 to paragraph
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(g): Nothing in this section is meant to preclude firefighters from performing emergency rescue 

activities before an entire team has assembled. 

(h) Maintenance and care of respirators. This paragraph requires the employer to provide for the 

cleaning and disinfecting, storage, inspection, and repair of respirators used by employees. 

 (1) Cleaning and disinfecting. The employer shall provide each respirator user with a 

respirator that is clean, sanitary, and in good working order. The employer shall ensure that 

respirators are cleaned and disinfected using the procedures in Appendix B-2 of this section, 

or procedures recommended by the respirator manufacturer, provided that such procedures 

are of equivalent effectiveness. The respirators shall be cleaned and disinfected at the 

following intervals: 

 (i) Respirators issued for the exclusive use of an employee shall be cleaned and 

disinfected as often as necessary to be maintained in a sanitary condition; 

 (ii) Respirators issued to more than one employee shall be cleaned and disinfected 

before being worn by different individuals; 

 (iii) Respirators maintained for emergency use shall be cleaned and disinfected after 

each use; and 

 (iv) Respirators used in fit testing and training shall be cleaned and disinfected after 

each use. 

 (2) Storage. The employer shall ensure that respirators are stored as follows: 

 (i) All respirators shall be stored to protect them from damage, contamination, dust, 

sunlight, extreme temperatures, excessive moisture, and damaging chemicals, and 

they shall be packed or stored to prevent deformation of the facepiece and exhalation 

valve. 

 (ii) In addition to the requirements of paragraph (h)(2)(i) of this section, emergency 

respirators shall be: 

 (A) Kept accessible to the work area; 

 (B) Stored in compartments or in covers that are clearly marked as containing 

emergency respirators; and 

 (C) Stored in accordance with any applicable manufacturer instructions. 

 (3) Inspection. (i) The employer shall ensure that respirators are inspected as follows: 

 (A) All respirators used in routine situations shall be inspected before each use 

and during cleaning; 
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 (B) All respirators maintained for use in emergency situations shall be 

inspected at least monthly and in accordance with the manufacturer's 

recommendations, and shall be checked for proper function before and after 

each use; and 

 (C) Emergency escape-only respirators shall be inspected before being carried 

into the workplace for use. 

 (ii) The employer shall ensure that respirator inspections include the following: 

 (A) A check of respirator function, tightness of connections, and the condition 

of the various parts including, but not limited to, the facepiece, head straps, 

valves, connecting tube, and cartridges, canisters or filters; and 

 (B) A check of elastomeric parts for pliability and signs of deterioration. 

 (iii) In addition to the requirements of paragraphs (h)(3)(i) and (ii) of this section, selfcontained breathing apparatus shall be inspected monthly. Air and oxygen cylinders 

shall be maintained in a fully charged state and shall be recharged when the pressure 

falls to 90% of the manufacturer's recommended pressure level. The employer shall 

determine that the regulator and warning devices function properly. 

 (iv) For respirators maintained for emergency use, the employer shall: 

 (A) Certify the respirator by documenting the date the inspection was 

performed, the name (or signature) of the person who made the inspection, the 

findings, required remedial action, and a serial number or other means of 

identifying the inspected respirator; and 

 (B) Provide this information on a tag or label that is attached to the storage 

compartment for the respirator, is kept with the respirator, or is included in 

inspection reports stored as paper or electronic files. This information shall be 

maintained until replaced following a subsequent certification. 

 (4) Repairs. The employer shall ensure that respirators that fail an inspection or are 

otherwise found to be defective are removed from service, and are discarded or repaired or 

adjusted in accordance with the following procedures: 

 (i) Repairs or adjustments to respirators are to be made only by persons appropriately 

trained to perform such operations and shall use only the respirator manufacturer's 

NIOSH-approved parts designed for the respirator; 

 (ii) Repairs shall be made according to the manufacturer's recommendations and 

specifications for the type and extent of repairs to be performed; and 

 (iii) Reducing and admission valves, regulators, and alarms shall be adjusted or 

repaired only by the manufacturer or a technician trained by the manufacturer. 
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(i) Breathing air quality and use. This paragraph requires the employer to provide employees using 

atmosphere-supplying respirators (supplied-air and SCBA) with breathing gases of high purity. 

 (1) The employer shall ensure that compressed air, compressed oxygen, liquid air, and liquid 

oxygen used for respiration accords with the following specifications: 

 (i) Compressed and liquid oxygen shall meet the United States Pharmacopoeia 

requirements for medical or breathing oxygen; and 

 (ii) Compressed breathing air shall meet at least the requirements for Grade D 

breathing air described in ANSI/Compressed Gas Association Commodity 

Specification for Air, G-7.1-1989, to include: 

 (A) Oxygen content (v/v) of 19.5-23.5%; 

 (B) Hydrocarbon (condensed) content of 5 milligrams per cubic meter of air or 

less; 

 (C) Carbon monoxide (CO) content of 10 ppm or less; 

 (D) Carbon dioxide content of 1,000 ppm or less; and 

 (E) Lack of noticeable odor. 

 (2) The employer shall ensure that compressed oxygen is not used in atmosphere-supplying 

respirators that have previously used compressed air. 

 (3) The employer shall ensure that oxygen concentrations greater than 23.5% are used only 

in equipment designed for oxygen service or distribution. 

 (4) The employer shall ensure that cylinders used to supply breathing air to respirators meet 

the following requirements: 

 (i) Cylinders are tested and maintained as prescribed in the Shipping Container 

Specification Regulations of the Department of Transportation (49 CFR part 173 and 

part 178); 

 (ii) Cylinders of purchased breathing air have a certificate of analysis from the supplier 

that the breathing air meets the requirements for Grade D breathing air; and 

 (iii) The moisture content in the cylinder does not exceed a dew point of -50 °F (-45.6 

°C) at 1 atmosphere pressure. 

 (5) The employer shall ensure that compressors used to supply breathing air to respirators 

are constructed and situated so as to: 

 (i) Prevent entry of contaminated air into the air-supply system; 
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 (ii) Minimize moisture content so that the dew point at 1 atmosphere pressure is 10 

degrees F (5.56 °C) below the ambient temperature; 

 (iii) Have suitable in-line air-purifying sorbent beds and filters to further ensure 

breathing air quality. Sorbent beds and filters shall be maintained and replaced or 

refurbished periodically following the manufacturer's instructions. 

 (iv) Have a tag containing the most recent change date and the signature of the 

person authorized by the employer to perform the change. The tag shall be maintained 

at the compressor. 

 (6) For compressors that are not oil-lubricated, the employer shall ensure that carbon 

monoxide levels in the breathing air do not exceed 10 ppm. 

 (7) For oil-lubricated compressors, the employer shall use a high-temperature or carbon 

monoxide alarm, or both, to monitor carbon monoxide levels. If only high-temperature alarms 

are used, the air supply shall be monitored at intervals sufficient to prevent carbon monoxide 

in the breathing air from exceeding 10 ppm. 

 (8) The employer shall ensure that breathing air couplings are incompatible with outlets for 

nonrespirable worksite air or other gas systems. No asphyxiating substance shall be 

introduced into breathing air lines. 

 (9) The employer shall use breathing gas containers marked in accordance with the NIOSH 

respirator certification standard, 42 CFR part 84. 

(j) Identification of filters, cartridges, and canisters. The employer shall ensure that all filters, 

cartridges and canisters used in the workplace are labeled and color coded with the NIOSH 

approval label and that the label is not removed and remains legible. 

(k) Training and information. This paragraph requires the employer to provide effective training to 

employees who are required to use respirators. The training must be comprehensive, 

understandable, and recur annually, and more often if necessary. This paragraph also requires the 

employer to provide the basic information on respirators in Appendix D of this section to employees 

who wear respirators when not required by this section or by the employer to do so. 

 (1) The employer shall ensure that each employee can demonstrate knowledge of at least 

the following: 

 (i) Why the respirator is necessary and how improper fit, usage, or maintenance can 

compromise the protective effect of the respirator; 

 (ii) What the limitations and capabilities of the respirator are; 

 (iii) How to use the respirator effectively in emergency situations, including situations 

in which the respirator malfunctions; 

 (iv) How to inspect, put on and remove, use, and check the seals of the respirator; 
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 (v) What the procedures are for maintenance and storage of the respirator; 

 (vi) How to recognize medical signs and symptoms that may limit or prevent the 

effective use of respirators; and 

 (vii) The general requirements of this section. 

 (2) The training shall be conducted in a manner that is understandable to the employee. 

 (3) The employer shall provide the training prior to requiring the employee to use a respirator 

in the workplace. 

 (4) An employer who is able to demonstrate that a new employee has received training 

within the last 12 months that addresses the elements specified in paragraph (k)(1)(i) through 

(vii) is not required to repeat such training provided that, as required by paragraph (k)(1), the 

employee can demonstrate knowledge of those element(s). Previous training not repeated 

initially by the employer must be provided no later than 12 months from the date of the 

previous training. 

 (5) Retraining shall be administered annually, and when the following situations occur: 

 (i) Changes in the workplace or the type of respirator render previous training 

obsolete; 

 (ii) Inadequacies in the employee's knowledge or use of the respirator indicate that the 

employee has not retained the requisite understanding or skill; or 

 (iii) Any other situation arises in which retraining appears necessary to ensure safe 

respirator use. 

 (6) The basic advisory information on respirators, as presented in Appendix D of this section, 

shall be provided by the employer in any written or oral format, to employees who wear 

respirators when such use is not required by this section or by the employer. 

(l) Program evaluation. This section requires the employer to conduct evaluations of the workplace 

to ensure that the written respiratory protection program is being properly implemented, and to 

consult employees to ensure that they are using the respirators properly. 

 (1) The employer shall conduct evaluations of the workplace as necessary to ensure that the 

provisions of the current written program are being effectively implemented and that it 

continues to be effective. 

 (2) The employer shall regularly consult employees required to use respirators to assess the 

employees' views on program effectiveness and to identify any problems. Any problems that 

are identified during this assessment shall be corrected. Factors to be assessed include, but 

are not limited to: 
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 (i) Respirator fit (including the ability to use the respirator without interfering with 

effective workplace performance); 

 (ii) Appropriate respirator selection for the hazards to which the employee is exposed; 

 (iii) Proper respirator use under the workplace conditions the employee encounters; 

and 

 (iv) Proper respirator maintenance. 

(m) Recordkeeping. This section requires the employer to establish and retain written information 

regarding medical evaluations, fit testing, and the respirator program. This information will facilitate 

employee involvement in the respirator program, assist the employer in auditing the adequacy of the 

program, and provide a record for compliance determinations by OSHA. 

 (1) Medical evaluation. Records of medical evaluations required by this section must be 

retained and made available in accordance with 29 CFR 1910.1020. 

 (2) Fit testing. (i) The employer shall establish a record of the qualitative and quantitative fit 

tests administered to an employee including: 

 (A) The name or identification of the employee tested; 

 (B) Type of fit test performed; 

 (C) Specific make, model, style, and size of respirator tested; 

 (D) Date of test; and 

 (E) The pass/fail results for QLFTs or the fit factor and strip chart recording or 

other recording of the test results for QNFTs. 

 (ii) Fit test records shall be retained for respirator users until the next fit test is 

administered. 

 (3) A written copy of the current respirator program shall be retained by the employer. 

 (4) Written materials required to be retained under this paragraph shall be made available 

upon request to affected employees and to the Assistant Secretary or designee for 

examination and copying. 

(n) Dates -- (1) Effective date. This section is effective April 8, 1998. The obligations imposed by this 

section commence on the effective date unless otherwise noted in this paragraph. Compliance with 

obligations that do not commence on the effective date shall occur no later than the applicable startup date. 

 (2) Compliance dates. All obligations of this section commence on the effective date except 

as follows: 
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 (i) The determination that respirator use is required (paragraph (a)) shall be 

completed no later than September 8, 1998. 

 (ii) Compliance with provisions of this section for all other provisions shall be 

completed no later than October 5, 1998. 

 (3) The provisions of 29 CFR 1910.134 and 29 CFR 1926.103, contained in the 29 CFR 

parts 1900 to 1910.99 and the 29 CFR part 1926 editions, revised as of July 1, 1997, are in 

effect and enforceable until October 5, 1998, or during any administrative or judicial stay of 

the provisions of this section. 

 (4) Existing respiratory protection programs. If, in the 12 month period preceding April 8, 

1998, the employer has conducted annual respirator training, fit testing, respirator program 

evaluation, or medical evaluations, the employer may use the results of those activities to 

comply with the corresponding provisions of this section, providing that these activities were 

conducted in a manner that meets the requirements of this section. 

(o) Appendices. (1) Compliance with Appendix A, Appendix B-1, Appendix B-2, and Appendix C of 

this section is mandatory. 

 (2) Appendix D of this section is non-mandatory and is not intended to create any additional 

obligations not otherwise imposed or to detract from any existing obligations. 

APPENDIX A TO §1910.134 -- FIT TESTING PROCEDURES (MANDATORY)

Part I. OSHA-Accepted Fit Test Protocols

A. Fit Testing Procedures -- General Requirements

The employer shall conduct fit testing using the following procedures. The requirements in this 

appendix apply to all OSHA-accepted fit test methods, both QLFT and QNFT. 

1. The test subject shall be allowed to pick the most acceptable respirator from a sufficient number 

of respirator models and sizes so that the respirator is acceptable to, and correctly fits, the user. 

2. Prior to the selection process, the test subject shall be shown how to put on a respirator, how it 

should be positioned on the face, how to set strap tension and how to determine an acceptable fit. A 

mirror shall be available to assist the subject in evaluating the fit and positioning of the respirator. 

This instruction may not constitute the subject's formal training on respirator use, because it is only a 

review. 
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3. The test subject shall be informed that he/she is being asked to select the respirator that provides 

the most acceptable fit. Each respirator represents a different size and shape, and if fitted and used 

properly, will provide adequate protection. 

4. The test subject shall be instructed to hold each chosen facepiece up to the face and eliminate 

those that obviously do not give an acceptable fit. 

5. The more acceptable facepieces are noted in case the one selected proves unacceptable; the 

most comfortable mask is donned and worn at least five minutes to assess comfort. Assistance in 

assessing comfort can be given by discussing the points in the following item A.6. If the test subject 

is not familiar with using a particular respirator, the test subject shall be directed to don the mask 

several times and to adjust the straps each time to become adept at setting proper tension on the 

straps. 

6. Assessment of comfort shall include a review of the following points with the test subject and 

allowing the test subject adequate time to determine the comfort of the respirator: 

(a) Position of the mask on the nose 

(b) Room for eye protection 

(c) Room to talk 

(d) Position of mask on face and cheeks 

7. The following criteria shall be used to help determine the adequacy of the respirator fit: 

(a) Chin properly placed; 

(b) Adequate strap tension, not overly tightened; 

(c) Fit across nose bridge; 

(d) Respirator of proper size to span distance from nose to chin; 

(e) Tendency of respirator to slip; 

(f) Self-observation in mirror to evaluate fit and respirator position. 

8. The test subject shall conduct a user seal check, either the negative and positive pressure seal 

checks described in Appendix B-1 of this section or those recommended by the respirator 

manufacturer which provide equivalent protection to the procedures in Appendix B-1. Before 

conducting the negative and positive pressure checks, the subject shall be told to seat the mask on 

the face by moving the head from side-to-side and up and down slowly while taking in a few slow 

deep breaths. Another facepiece shall be selected and retested if the test subject fails the user seal 

check tests. 
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9. The test shall not be conducted if there is any hair growth between the skin and the facepiece 

sealing surface, such as stubble beard growth, beard, mustache or sideburns which cross the 

respirator sealing surface. Any type of apparel which interferes with a satisfactory fit shall be altered 

or removed. 

10. If a test subject exhibits difficulty in breathing during the tests, she or he shall be referred to a 

physician or other licensed health care professional, as appropriate, to determine whether the test 

subject can wear a respirator while performing her or his duties. 

11. If the employee finds the fit of the respirator unacceptable, the test subject shall be given the 

opportunity to select a different respirator and to be retested. 

12. Exercise regimen. Prior to the commencement of the fit test, the test subject shall be given a 

description of the fit test and the test subject's responsibilities during the test procedure. The 

description of the process shall include a description of the test exercises that the subject will be 

performing. The respirator to be tested shall be worn for at least 5 minutes before the start of the fit 

test. 

13. The fit test shall be performed while the test subject is wearing any applicable safety equipment 

that may be worn during actual respirator use which could interfere with respirator fit. 

14. Test Exercises. (a) The following test exercises are to be performed for all fit testing methods 

prescribed in this appendix, except for the CNP method. A separate fit testing exercise regimen is 

contained in the CNP protocol. The test subject shall perform exercises, in the test environment, in 

the following manner: 

 (1) Normal breathing. In a normal standing position, without talking, the subject shall breathe 

normally. 

 (2) Deep breathing. In a normal standing position, the subject shall breathe slowly and 

deeply, taking caution so as not to hyperventilate. 

 (3) Turning head side to side. Standing in place, the subject shall slowly turn his/her head 

from side to side between the extreme positions on each side. The head shall be held at each 

extreme momentarily so the subject can inhale at each side. 

 (4) Moving head up and down. Standing in place, the subject shall slowly move his/her head 

up and down. The subject shall be instructed to inhale in the up position (i.e., when looking 

toward the ceiling). 

 (5) Talking. The subject shall talk out loud slowly and loud enough so as to be heard clearly 

by the test conductor. The subject can read from a prepared text such as the Rainbow 

Passage, count backward from 100, or recite a memorized poem or song. 
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Rainbow Passage

 When the sunlight strikes raindrops in the air, they act like a prism and form a rainbow. The 

rainbow is a division of white light into many beautiful colors. These take the shape of a long 

round arch, with its path high above, and its two ends apparently beyond the horizon. There 

is, according to legend, a boiling pot of gold at one end. People look, but no one ever finds it. 

When a man looks for something beyond reach, his friends say he is looking for the pot of 

gold at the end of the rainbow. 

 (6) Grimace. The test subject shall grimace by smiling or frowning. (This applies only to 

QNFT testing; it is not performed for QLFT) 

 (7) Bending over. The test subject shall bend at the waist as if he/she were to touch his/her 

toes. Jogging in place shall be substituted for this exercise in those test environments such 

as shroud type QNFT or QLFT units that do not permit bending over at the waist. 

 (8) Normal breathing. Same as exercise (1). 

(b) Each test exercise shall be performed for one minute except for the grimace exercise which shall 

be performed for 15 seconds. The test subject shall be questioned by the test conductor regarding 

the comfort of the respirator upon completion of the protocol. If it has become unacceptable, another 

model of respirator shall be tried. The respirator shall not be adjusted once the fit test exercises 

begin. Any adjustment voids the test, and the fit test must be repeated. 

B. Qualitative Fit Test (QLFT) Protocols

1. General

(a) The employer shall ensure that persons administering QLFT are able to prepare test solutions, 

calibrate equipment and perform tests properly, recognize invalid tests, and ensure that test 

equipment is in proper working order. 

(b) The employer shall ensure that QLFT equipment is kept clean and well maintained so as to 

operate within the parameters for which it was designed. 

2. Isoamyl Acetate Protocol

Note:

This protocol is not appropriate to use for the fit testing of particulate respirators. If used to fit test 

particulate respirators, the respirator must be equipped with an organic vapor filter. 
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(a) Odor Threshold Screening

Odor threshold screening, performed without wearing a respirator, is intended to determine if the 

individual tested can detect the odor of isoamyl acetate at low levels. 

(1) Three 1 liter glass jars with metal lids are required. 

(2) Odor-free water (e.g., distilled or spring water) at approximately 25 °C (77 °F) shall be used for 

the solutions. 

(3) The isoamyl acetate (IAA) (also known at isopentyl acetate) stock solution is prepared by adding 

1 ml of pure IAA to 800 ml of odor-free water in a 1 liter jar, closing the lid and shaking for 30 

seconds. A new solution shall be prepared at least weekly. 

(4) The screening test shall be conducted in a room separate from the room used for actual fit 

testing. The two rooms shall be well-ventilated to prevent the odor of IAA from becoming evident in 

the general room air where testing takes place. 

(5) The odor test solution is prepared in a second jar by placing 0.4 ml of the stock solution into 500 

ml of odor-free water using a clean dropper or pipette. The solution shall be shaken for 30 seconds 

and allowed to stand for two to three minutes so that the IAA concentration above the liquid may 

reach equilibrium. This solution shall be used for only one day. 

(6) A test blank shall be prepared in a third jar by adding 500 cc of odor-free water. 

(7) The odor test and test blank jar lids shall be labeled (e.g., 1 and 2) for jar identification. Labels 

shall be placed on the lids so that they can be peeled off periodically and switched to maintain the 

integrity of the test. 

(8) The following instruction shall be typed on a card and placed on the table in front of the two test 

jars (i.e., 1 and 2): "The purpose of this test is to determine if you can smell banana oil at a low 

concentration. The two bottles in front of you contain water. One of these bottles also contains a 

small amount of banana oil. Be sure the covers are on tight, then shake each bottle for two seconds. 

Unscrew the lid of each bottle, one at a time, and sniff at the mouth of the bottle. Indicate to the test 

conductor which bottle contains banana oil." 

(9) The mixtures used in the IAA odor detection test shall be prepared in an area separate from 

where the test is performed, in order to prevent olfactory fatigue in the subject. 

(10) If the test subject is unable to correctly identify the jar containing the odor test solution, the IAA 

qualitative fit test shall not be performed. 

(11) If the test subject correctly identifies the jar containing the odor test solution, the test subject 

may proceed to respirator selection and fit testing. 
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(b) Isoamyl Acetate Fit Test

(1) The fit test chamber shall be a clear 55-gallon drum liner suspended inverted over a 2-foot 

diameter frame so that the top of the chamber is about 6 inches above the test subject's head. If no 

drum liner is available, a similar chamber shall be constructed using plastic sheeting. The inside top 

center of the chamber shall have a small hook attached. 

(2) Each respirator used for the fitting and fit testing shall be equipped with organic vapor cartridges 

or offer protection against organic vapors. 

(3) After selecting, donning, and properly adjusting a respirator, the test subject shall wear it to the fit 

testing room. This room shall be separate from the room used for odor threshold screening and 

respirator selection, and shall be well-ventilated, as by an exhaust fan or lab hood, to prevent 

general room contamination. 

(4) A copy of the test exercises and any prepared text from which the subject is to read shall be 

taped to the inside of the test chamber. 

(5) Upon entering the test chamber, the test subject shall be given a 6-inch by 5-inch piece of paper 

towel, or other porous, absorbent, single-ply material, folded in half and wetted with 0.75 ml of pure 

IAA. The test subject shall hang the wet towel on the hook at the top of the chamber. An IAA test 

swab or ampule may be substituted for the IAA wetted paper towel provided it has been 

demonstrated that the alternative IAA source will generate an IAA test atmosphere with a 

concentration equivalent to that generated by the paper towel method. 

(6) Allow two minutes for the IAA test concentration to stabilize before starting the fit test exercises. 

This would be an appropriate time to talk with the test subject; to explain the fit test, the importance 

of his/her cooperation, and the purpose for the test exercises; or to demonstrate some of the 

exercises. 

(7) If at any time during the test, the subject detects the banana-like odor of IAA, the test is failed. 

The subject shall quickly exit from the test chamber and leave the test area to avoid olfactory 

fatigue. 

(8) If the test is failed, the subject shall return to the selection room and remove the respirator. The 

test subject shall repeat the odor sensitivity test, select and put on another respirator, return to the 

test area and again begin the fit test procedure described in (b) (1) through (7) above. The process 

continues until a respirator that fits well has been found. Should the odor sensitivity test be failed, 

the subject shall wait at least 5 minutes before retesting. Odor sensitivity will usually have returned 

by this time. 

(9) If the subject passes the test, the efficiency of the test procedure shall be demonstrated by 

having the subject break the respirator face seal and take a breath before exiting the chamber. 

(10) When the test subject leaves the chamber, the subject shall remove the saturated towel and 

return it to the person conducting the test, so that there is no significant IAA concentration buildup in 

the chamber during subsequent tests. The used towels shall be kept in a self-sealing plastic bag to 

keep the test area from being contaminated. 
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3. Saccharin Solution Aerosol Protocol

The entire screening and testing procedure shall be explained to the test subject prior to the conduct 

of the screening test. 

(a) Taste threshold screening. The saccharin taste threshold screening, performed without wearing 

a respirator, is intended to determine whether the individual being tested can detect the taste of 

saccharin. 

 (1) During threshold screening as well as during fit testing, subjects shall wear an enclosure 

about the head and shoulders that is approximately 12 inches in diameter by 14 inches tall 

with at least the front portion clear and that allows free movements of the head when a 

respirator is worn. An enclosure substantially similar to the 3M hood assembly, parts # FT 14 

and # FT 15 combined, is adequate. 

 (2) The test enclosure shall have a 3/4-inch (1.9 cm) hole in front of the test subject's nose 

and mouth area to accommodate the nebulizer nozzle. 

 (3) The test subject shall don the test enclosure. Throughout the threshold screening test, 

the test subject shall breathe through his/her slightly open mouth with tongue extended. The 

subject is instructed to report when he/she detects a sweet taste. 

 (4) Using a DeVilbiss Model 40 Inhalation Medication Nebulizer or equivalent, the test 

conductor shall spray the threshold check solution into the enclosure. The nozzle is directed 

away from the nose and mouth of the person. This nebulizer shall be clearly marked to 

distinguish it from the fit test solution nebulizer. 

 (5) The threshold check solution is prepared by dissolving 0.83 gram of sodium saccharin 

USP in 100 ml of warm water. It can be prepared by putting 1 ml of the fit test solution (see 

(b)(5) below) in 100 ml of distilled water. 

 (6) To produce the aerosol, the nebulizer bulb is firmly squeezed so that it collapses 

completely, then released and allowed to fully expand. 

 (7) Ten squeezes are repeated rapidly and then the test subject is asked whether the 

saccharin can be tasted. If the test subject reports tasting the sweet taste during the ten 

squeezes, the screening test is completed. The taste threshold is noted as ten regardless of 

the number of squeezes actually completed. 

 (8) If the first response is negative, ten more squeezes are repeated rapidly and the test 

subject is again asked whether the saccharin is tasted. If the test subject reports tasting the 

sweet taste during the second ten squeezes, the screening test is completed. The taste 

threshold is noted as twenty regardless of the number of squeezes actually completed. 

 (9) If the second response is negative, ten more squeezes are repeated rapidly and the test 

subject is again asked whether the saccharin is tasted. If the test subject reports tasting the 

sweet taste during the third set of ten squeezes, the screening test is completed. The taste 

threshold is noted as thirty regardless of the number of squeezes actually completed. 
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 (10) The test conductor will take note of the number of squeezes required to solicit a taste 

response. 

 (11) If the saccharin is not tasted after 30 squeezes (step 10), the test subject is unable to 

taste saccharin and may not perform the saccharin fit test. 

 Note to paragraph 3. 

 (a): If the test subject eats or drinks something sweet before the screening test, 

he/she may be unable to taste the weak saccharin solution. 

 (12) If a taste response is elicited, the test subject shall be asked to take note of the taste for 

reference in the fit test. 

 (13) Correct use of the nebulizer means that approximately 1 ml of liquid is used at a time in 

the nebulizer body. 

 (14) The nebulizer shall be thoroughly rinsed in water, shaken dry, and refilled at least each 

morning and afternoon or at least every four hours. 

(b) Saccharin solution aerosol fit test procedure. 

 (1) The test subject may not eat, drink (except plain water), smoke, or chew gum for 15 

minutes before the test. 

 (2) The fit test uses the same enclosure described in 3. (a) above. 

 (3) The test subject shall don the enclosure while wearing the respirator selected in section I. 

A. of this appendix. The respirator shall be properly adjusted and equipped with a particulate 

filter(s). 

 (4) A second DeVilbiss Model 40 Inhalation Medication Nebulizer or equivalent is used to 

spray the fit test solution into the enclosure. This nebulizer shall be clearly marked to 

distinguish it from the screening test solution nebulizer. 

 (5) The fit test solution is prepared by adding 83 grams of sodium saccharin to 100 ml of 

warm water. 

 (6) As before, the test subject shall breathe through the slightly open mouth with tongue 

extended, and report if he/she tastes the sweet taste of saccharin. 

 (7) The nebulizer is inserted into the hole in the front of the enclosure and an initial 

concentration of saccharin fit test solution is sprayed into the enclosure using the same 

number of squeezes (either 10, 20 or 30 squeezes) based on the number of squeezes 
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required to elicit a taste response as noted during the screening test. A minimum of 10 

squeezes is required. 

 (8) After generating the aerosol, the test subject shall be instructed to perform the exercises 

in section I. A. 14. of this appendix. 

 (9) Every 30 seconds the aerosol concentration shall be replenished using one half the 

original number of squeezes used initially (e.g., 5, 10 or 15). 

 (10) The test subject shall indicate to the test conductor if at any time during the fit test the 

taste of saccharin is detected. If the test subject does not report tasting the saccharin, the test 

is passed. 

 (11) If the taste of saccharin is detected, the fit is deemed unsatisfactory and the test is 

failed. A different respirator shall be tried and the entire test procedure is repeated (taste 

threshold screening and fit testing). 

 (12) Since the nebulizer has a tendency to clog during use, the test Shell must make periodic 

checks of the nebulizer to ensure that it is not clogged. If clogging is found at the end of the 

test session, the test is invalid. 

4. BitrexTM (Denatonium Benzoate) Solution Aerosol Qualitative Fit Test Protocol

The BitrexTM (Denatonium benzoate) solution aerosol QLFT protocol uses the published saccharin 

test protocol because that protocol is widely accepted. Bitrex is routinely used as a taste aversion 

agent in household liquids which children should not be drinking and is endorsed by the American 

Medical Association, the National Safety Council, and the American Association of Poison Control 

Centers. The entire screening and testing procedure shall be explained to the test subject prior to 

the conduct of the screening test. 

(a) Taste Threshold Screening. 

The Bitrex taste threshold screening, performed without wearing a respirator, is intended to 

determine whether the individual being tested can detect the taste of Bitrex. 

 (1) During threshold screening as well as during fit testing, subjects shall wear an enclosure 

about the head and shoulders that is approximately 12 inches (30.5 cm) in diameter by 14 

inches (35.6 cm) tall. The front portion of the enclosure shall be clear from the respirator and 

allow free movement of the head when a respirator is worn. An enclosure substantially similar 

to the 3M hood assembly, parts # FT 14 and # FT 15 combined, is adequate. 

 (2) The test enclosure shall have a 3/4 inch (1.9 cm) hole in front of the test subject's nose 

and mouth area to accommodate the nebulizer nozzle. 

 (3) The test subject shall don the test enclosure. Throughout the threshold screening test, 

the test subject shall breathe through his or her slightly open mouth with tongue extended. 

The subject is instructed to report when he/she detects a bitter taste. 
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 (4) Using a DeVilbiss Model 40 Inhalation Medication Nebulizer or equivalent, the test 

conductor shall spray the Threshold Check Solution into the enclosure. This Nebulizer shall 

be clearly marked to distinguish it from the fit test solution nebulizer. 

 (5) The Threshold Check Solution is prepared by adding 13.5 milligrams of Bitrex to 100 ml 

of 5% salt (NaCl) solution in distilled water. 

 (6) To produce the aerosol, the nebulizer bulb is firmly squeezed so that the bulb collapses 

completely, and is then released and allowed to fully expand. 

 (7) An initial ten squeezes are repeated rapidly and then the test subject is asked whether 

the Bitrex can be tasted. If the test subject reports tasting the bitter taste during the ten 

squeezes, the screening test is completed. The taste threshold is noted as ten regardless of 

the number of squeezes actually completed. 

 (8) If the first response is negative, ten more squeezes are repeated rapidly and the test 

subject is again asked whether the Bitrex is tasted. If the test subject reports tasting the bitter 

taste during the second ten squeezes, the screening test is completed. The taste threshold is 

noted as twenty regardless of the number of squeezes actually completed. 

 (9) If the second response is negative, ten more squeezes are repeated rapidly and the test 

subject is again asked whether the Bitrex is tasted. If the test subject reports tasting the bitter 

taste during the third set of ten squeezes, the screening test is completed. The taste 

threshold is noted as thirty regardless of the number of squeezes actually completed. 

 (10) The test conductor will take note of the number of squeezes required to solicit a taste 

response. 

 (11) If the Bitrex is not tasted after 30 squeezes (step 10), the test subject is unable to taste 

Bitrex and may not perform the Bitrex fit test. 

 (12) If a taste response is elicited, the test subject shall be asked to take note of the taste for 

reference in the fit test. 

 (13) Correct use of the nebulizer means that approximately 1 ml of liquid is used at a time in 

the nebulizer body. 

 (14) The nebulizer shall be thoroughly rinsed in water, shaken to dry, and refilled at least 

each morning and afternoon or at least every four hours. 

(b) Bitrex Solution Aerosol Fit Test Procedure. 

 (1) The test subject may not eat, drink (except plain water), smoke, or chew gum for 15 

minutes before the test. 

 (2) The fit test uses the same enclosure as that described in 4. (a) above. 
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 (3) The test subject shall don the enclosure while wearing the respirator selected according 

to section I. A. of this appendix. The respirator shall be properly adjusted and equipped with 

any type particulate filter(s). 

 (4) A second DeVilbiss Model 40 Inhalation Medication Nebulizer or equivalent is used to 

spray the fit test solution into the enclosure. This nebulizer shall be clearly marked to 

distinguish it from the screening test solution nebulizer. 

 (5) The fit test solution is prepared by adding 337.5 mg of Bitrex to 200 ml of a 5% salt 

(NaCl) solution in warm water. 

 (6) As before, the test subject shall breathe through his or her slightly open mouth with 

tongue extended, and be instructed to report if he/she tastes the bitter taste of Bitrex.. 

 (7) The nebulizer is inserted into the hole in the front of the enclosure and an initial 

concentration of the fit test solution is sprayed into the enclosure using the same number of 

squeezes (either 10, 20 or 30 squeezes) based on the number of squeezes required to elicit 

a taste response as noted during the screening test. 

 (8) After generating the aerosol, the test subject shall be instructed to perform the exercises 

in section I. A. 14. of this appendix. 

 (9) Every 30 seconds the aerosol concentration shall be replenished using one half the 

number of squeezes used initially (e.g., 5, 10 or 15). 

 (10) The test subject shall indicate to the test conductor if at any time during the fit test the 

taste of Bitrex is detected. If the test subject does not report tasting the Bitrex, the test is 

passed. 

 (11) If the taste of Bitrex is detected, the fit is deemed unsatisfactory and the test is failed. A 

different respirator shall be tried and the entire test procedure is repeated (taste threshold 

screening and fit testing). 

5. Irritant Smoke (Stannic Chloride) Protocol

This qualitative fit test uses a person's response to the irritating chemicals released in the "smoke" 

produced by a stannic chloride ventilation smoke tube to detect leakage into the respirator. 

(a) General Requirements and Precautions

(1) The respirator to be tested shall be equipped with high efficiency particulate air (HEPA) or P100 

series filter(s). 

(2) Only stannic chloride smoke tubes shall be used for this protocol. 

(3) No form of test enclosure or hood for the test subject shall be used. 
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(4) The smoke can be irritating to the eyes, lungs, and nasal passages. The test conductor shall 

take precautions to minimize the test subject's exposure to irritant smoke. Sensitivity varies, and 

certain individuals may respond to a greater degree to irritant smoke. Care shall be taken when 

performing the sensitivity screening checks that determine whether the test subject can detect 

irritant smoke to use only the minimum amount of smoke necessary to elicit a response from the test 

subject. 

(5) The fit test shall be performed in an area with adequate ventilation to prevent exposure of the 

person conducting the fit test or the build-up of irritant smoke in the general atmosphere. 

(b) Sensitivity Screening Check

The person to be tested must demonstrate his or her ability to detect a weak concentration of the 

irritant smoke. 

(1) The test Shell shall break both ends of a ventilation smoke tube containing stannic chloride, and 

attach one end of the smoke tube to a low flow air pump set to deliver 200 milliliters per minute, or 

an aspirator squeeze bulb. The test Shell shall cover the other end of the smoke tube with a short 

piece of tubing to prevent potential injury from the jagged end of the smoke tube. 

(2) The test Shell shall advise the test subject that the smoke can be irritating to the eyes, lungs, 

and nasal passages and instruct the subject to keep his/her eyes closed while the test is performed. 

(3) The test subject shall be allowed to smell a weak concentration of the irritant smoke before the 

respirator is donned to become familiar with its irritating properties and to determine if he/she can 

detect the irritating properties of the smoke. The test Shell shall carefully direct a small amount of 

the irritant smoke in the test subject's direction to determine that he/she can detect it. 

(c) Irritant Smoke Fit Test Procedure

(1) The person being fit tested shall don the respirator without assistance, and perform the required 

user seal check(s). 

(2) The test subject shall be instructed to keep his/her eyes closed. 

(3) The test Shell shall direct the stream of irritant smoke from the smoke tube toward the faceseal 

area of the test subject, using the low flow pump or the squeeze bulb. The test Shell shall begin at 

least 12 inches from the facepiece and move the smoke stream around the whole perimeter of the 

mask. The Shell shall gradually make two more passes around the perimeter of the mask, moving to 

within six inches of the respirator. 

(4) If the person being tested has not had an involuntary response and/or detected the irritant 

smoke, proceed with the test exercises. 
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(5) The exercises identified in section I.A. 14. of this appendix shall be performed by the test subject 

while the respirator seal is being continually challenged by the smoke, directed around the perimeter 

of the respirator at a distance of six inches. 

(6) If the person being fit tested reports detecting the irritant smoke at any time, the test is failed. 

The person being retested must repeat the entire sensitivity check and fit test procedure. 

(7) Each test subject passing the irritant smoke test without evidence of a response (involuntary 

cough, irritation) shall be given a second sensitivity screening check, with the smoke from the same 

smoke tube used during the fit test, once the respirator has been removed, to determine whether 

he/she still reacts to the smoke. Failure to evoke a response shall void the fit test. 

(8) If a response is produced during this second sensitivity check, then the fit test is passed. 

C. Quantitative Fit Test (QNFT) Protocols

The following quantitative fit testing procedures have been demonstrated to be acceptable: 

Quantitative fit testing using a non-hazardous test aerosol (such as corn oil, polyethylene glycol 400 

[PEG 400], di-2-ethyl hexyl sebacate [DEHS], or sodium chloride) generated in a test chamber, and 

employing instrumentation to quantify the fit of the respirator; Quantitative fit testing using ambient 

aerosol as the test agent and appropriate instrumentation (condensation nuclei counter) to quantify 

the respirator fit; Quantitative fit testing using controlled negative pressure and appropriate 

instrumentation to measure the volumetric leak rate of a facepiece to quantify the respirator fit. 

1. General

(a) The employer shall ensure that persons administering QNFT are able to calibrate equipment and 

perform tests properly, recognize invalid tests, calculate fit factors properly and ensure that test 

equipment is in proper working order. 

(b) The employer shall ensure that QNFT equipment is kept clean, and is maintained and calibrated 

according to the manufacturer's instructions so as to operate at the parameters for which it was 

designed. 

2. Generated Aerosol Quantitative Fit Testing Protocol

(a) Apparatus. 

 (1) Instrumentation. Aerosol generation, dilution, and measurement systems using 

particulates (corn oil, polyethylene glycol 400 [PEG 400], di-2-ethyl hexyl sebacate [DEHS] or 

sodium chloride) as test aerosols shall be used for quantitative fit testing. 

 (2) Test chamber. The test chamber shall be large enough to permit all test subjects to 

perform freely all required exercises without disturbing the test agent concentration or the 

measurement apparatus. The test chamber shall be equipped and constructed so that the 
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test agent is effectively isolated from the ambient air, yet uniform in concentration throughout 

the chamber. 

 (3) When testing air-purifying respirators, the normal filter or cartridge element shall be 

replaced with a high efficiency particulate air (HEPA) or P100 series filter supplied by the 

same manufacturer. 

 (4) The sampling instrument shall be selected so that a computer record or strip chart record 

may be made of the test showing the rise and fall of the test agent concentration with each 

inspiration and expiration at fit factors of at least 2,000. Integrators or computers that 

integrate the amount of test agent penetration leakage into the respirator for each exercise 

may be used provided a record of the readings is made. 

 (5) The combination of substitute air-purifying elements, test agent and test agent 

concentration shall be such that the test subject is not exposed in excess of an established 

exposure limit for the test agent at any time during the testing process, based upon the length 

of the exposure and the exposure limit duration. 

 (6) The sampling port on the test specimen respirator shall be placed and constructed so 

that no leakage occurs around the port (e.g., where the respirator is probed), a free air flow is 

allowed into the sampling line at all times, and there is no interference with the fit or 

performance of the respirator. The in-mask sampling device (probe) shall be designed and 

used so that the air sample is drawn from the breathing zone of the test subject, midway 

between the nose and mouth and with the probe extending into the facepiece cavity at least 

1/4 inch. 

 (7) The test setup shall permit the person administering the test to observe the test subject 

inside the chamber during the test. 

 (8) The equipment generating the test atmosphere shall maintain the concentration of test 

agent constant to within a 10 percent variation for the duration of the test. 

 (9) The time lag (interval between an event and the recording of the event on the strip chart 

or computer or integrator) shall be kept to a minimum. There shall be a clear association 

between the occurrence of an event and its being recorded. 

 (10) The sampling line tubing for the test chamber atmosphere and for the respirator 

sampling port shall be of equal diameter and of the same material. The length of the two lines 

shall be equal. 

 (11) The exhaust flow from the test chamber shall pass through an appropriate filter (i.e., 

high efficiency particulate filter) before release. 

 (12) When sodium chloride aerosol is used, the relative humidity inside the test chamber 

shall not exceed 50 percent. 

 (13) The limitations of instrument detection shall be taken into account when determining the 

fit factor. 
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 (14) Test respirators shall be maintained in proper working order and be inspected regularly 

for deficiencies such as cracks or missing valves and gaskets. 

(b) Procedural Requirements. 

 (1) When performing the initial user seal check using a positive or negative pressure check, 

the sampling line shall be crimped closed in order to avoid air pressure leakage during either 

of these pressure checks. 

 (2) The use of an abbreviated screening QLFT test is optional. Such a test may be utilized in 

order to quickly identify poor fitting respirators that passed the positive and/or negative 

pressure test and reduce the amount of QNFT time. The use of the CNC QNFT instrument in 

the count mode is another optional method to obtain a quick estimate of fit and eliminate poor 

fitting respirators before going on to perform a full QNFT. 

 (3) A reasonably stable test agent concentration shall be measured in the test chamber prior 

to testing. For canopy or shower curtain types of test units, the determination of the test 

agent's stability may be established after the test subject has entered the test environment. 

 (4) Immediately after the subject enters the test chamber, the test agent concentration inside 

the respirator shall be measured to ensure that the peak penetration does not exceed 5 

percent for a half mask or 1 percent for a full facepiece respirator. 

 (5) A stable test agent concentration shall be obtained prior to the actual start of testing. 

 (6) Respirator restraining straps shall not be over-tightened for testing. The straps shall be 

adjusted by the wearer without assistance from other persons to give a reasonably 

comfortable fit typical of normal use. The respirator shall not be adjusted once the fit test 

exercises begin. 

 (7) The test shall be terminated whenever any single peak penetration exceeds 5 percent for 

half masks and 1 percent for full facepiece respirators. The test subject shall be refitted and 

retested. 

 (8) Calculation of fit factors. 

 (i) The fit factor shall be determined for the quantitative fit test by taking the ratio of 

the average chamber concentration to the concentration measured inside the 

respirator for each test exercise except the grimace exercise. 

 (ii) The average test chamber concentration shall be calculated as the arithmetic 

average of the concentration measured before and after each test (i.e., 7 exercises) or 

the arithmetic average of the concentration measured before and after each exercise 

or the true average measured continuously during the respirator sample. 

 (iii) The concentration of the challenge agent inside the respirator shall be determined 

by one of the following methods: 
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 ( A ) Average peak penetration method means the method of determining test 

agent penetration into the respirator utilizing a strip chart recorder, integrator, or 

computer. The agent penetration is determined by an average of the peak 

heights on the graph or by computer integration, for each exercise except the 

grimace exercise. Integrators or computers that calculate the actual test agent 

penetration into the respirator for each exercise will also be considered to meet 

the requirements of the average peak penetration method. 

 ( B ) Maximum peak penetration method means the method of determining test 

agent penetration in the respirator as determined by strip chart recordings of the 

test. The highest peak penetration for a given exercise is taken to be 

representative of average penetration into the respirator for that exercise. 

 ( C ) Integration by calculation of the area under the individual peak for each 

exercise except the grimace exercise. This includes computerized integration. 

 ( D ) The calculation of the overall fit factor using individual exercise fit factors 

involves first converting the exercise fit factors to penetration values, 

determining the average, and then converting that result back to a fit factor. 

This procedure is described in the following equation: 

 [A graphic goes here] 

 Where ff1, ff2, ff3, etc. are the fit factors for exercises 1, 2, 3, etc. 

 (9) The test subject shall not be permitted to wear a half mask or quarter facepiece respirator 

unless a minimum fit factor of 100 is obtained, or a full facepiece respirator unless a minimum 

fit factor of 500 is obtained. 

 (10) Filters used for quantitative fit testing shall be replaced whenever increased breathing 

resistance is encountered, or when the test agent has altered the integrity of the filter media. 

3. Ambient aerosol condensation nuclei counter (CNC) quantitative fit testing protocol. 

The ambient aerosol condensation nuclei counter (CNC) quantitative fit testing (PortacountTM ) 

protocol quantitatively fit tests respirators with the use of a probe. The probed respirator is only used 

for quantitative fit tests. A probed respirator has a special sampling device, installed on the 

respirator, that allows the probe to sample the air from inside the mask. A probed respirator is 

required for each make, style, model, and size that the employer uses and can be obtained from the 

respirator manufacturer or distributor. The CNC instrument manufacturer, TSI Inc., also provides 

probe attachments (TSI sampling adapters) that permit fit testing in an employee's own respirator. A 

minimum fit factor pass level of at least 100 is necessary for a half-mask respirator and a minimum 

fit factor pass level of at least 500 is required for a full facepiece negative pressure respirator. The 

entire screening and testing procedure shall be explained to the test subject prior to the conduct of 

the screening test. 
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(a) Portacount Fit Test Requirements. (1) Check the respirator to make sure the sampling probe and 

line are properly attached to the facepiece and that the respirator is fitted with a particulate filter 

capable of preventing significant penetration by the ambient particles used for the fit test (e.g., 

NIOSH 42 CFR 84 series 100, series 99, or series 95 particulate filter) per manufacturer's 

instruction. 

(2) Instruct the person to be tested to don the respirator for five minutes before the fit test starts. 

This purges the ambient particles trapped inside the respirator and permits the wearer to make 

certain the respirator is comfortable. This individual shall already have been trained on how to wear 

the respirator properly. 

(3) Check the following conditions for the adequacy of the respirator fit: Chin properly placed; 

Adequate strap tension, not overly tightened; Fit across nose bridge; Respirator of proper size to 

span distance from nose to chin; Tendency of the respirator to slip; Self-observation in a mirror to 

evaluate fit and respirator position. 

(4) Have the person wearing the respirator do a user seal check. If leakage is detected, determine 

the cause. If leakage is from a poorly fitting facepiece, try another size of the same model respirator, 

or another model of respirator. 

(5) Follow the manufacturer's instructions for operating the Portacount and proceed with the test. 

(6) The test subject shall be instructed to perform the exercises in section I. A. 14. of this appendix. 

(7) After the test exercises, the test subject shall be questioned by the test conductor regarding the 

comfort of the respirator upon completion of the protocol. If it has become unacceptable, another 

model of respirator shall be tried. 

(b) Portacount Test Instrument. 

 (1) The Portacount will automatically stop and calculate the overall fit factor for the entire set 

of exercises. The overall fit factor is what counts. The Pass or Fail message will indicate 

whether or not the test was successful. If the test was a Pass, the fit test is over. 

 (2) Since the pass or fail criterion of the Portacount is user programmable, the test Shell 

shall ensure that the pass or fail criterion meet the requirements for minimum respirator 

performance in this Appendix. 

 (3) A record of the test needs to be kept on file, assuming the fit test was successful. The 

record must contain the test subject's name; overall fit factor; make, model, style, and size of 

respirator used; and date tested. 

4. Controlled negative pressure (CNP) quantitative fit testing protocol. 

The CNP protocol provides an alternative to aerosol fit test methods. The CNP fit test method 

technology is based on exhausting air from a temporarily sealed respirator facepiece to generate 

and then maintain a constant negative pressure inside the facepiece. The rate of air exhaust is 

controlled so that a constant negative pressure is maintained in the respirator during the fit test. The 
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level of pressure is selected to replicate the mean inspiratory pressure that causes leakage into the 

respirator under normal use conditions. With pressure held constant, air flow out of the respirator is 

equal to air flow into the respirator. Therefore, measurement of the exhaust stream that is required 

to hold the pressure in the temporarily sealed respirator constant yields a direct measure of leakage 

air flow into the respirator. The CNP fit test method measures leak rates through the facepiece as a 

method for determining the facepiece fit for negative pressure respirators. The CNP instrument 

manufacturer Dynatech Nevada also provides attachments (sampling manifolds) that replace the 

filter cartridges to permit fit testing in an employee's own respirator. To perform the test, the test 

subject closes his or her mouth and holds his/her breath, after which an air pump removes air from 

the respirator facepiece at a pre-selected constant pressure. The facepiece fit is expressed as the 

leak rate through the facepiece, expressed as milliliters per minute. The quality and validity of the 

CNP fit tests are determined by the degree to which the in-mask pressure tracks the test pressure 

during the system measurement time of approximately five seconds. Instantaneous feedback in the 

form of a real-time pressure trace of the in-mask pressure is provided and used to determine test 

validity and quality. A minimum fit factor pass level of 100 is necessary for a half-mask respirator 

and a minimum fit factor of at least 500 is required for a full facepiece respirator. The entire 

screening and testing procedure shall be explained to the test subject prior to the conduct of the 

screening test. 

(a) CNP Fit Test Requirements. 

 (1) The instrument shall have a non-adjustable test pressure of 15.0 mm water pressure. 

 (2) The CNP system defaults selected for test pressure shall be set at -15 mm of water (-

0.58 inches of water) and the modeled inspiratory flow rate shall be 53.8 liters per minute for 

performing fit tests. 

 Note: 

 CNP systems have built-in capability to conduct fit testing that is specific to unique work rate, 

mask, and gender situations that might apply in a specific workplace. Use of system default 

values, which were selected to represent respirator wear with medium cartridge resistance at 

a low-moderate work rate, will allow inter-test comparison of the respirator fit.) 

 (3) The individual who conducts the CNP fit testing shall be thoroughly trained to perform the 

test. 

 (4) The respirator filter or cartridge needs to be replaced with the CNP test manifold. The 

inhalation valve downstream from the manifold either needs to be temporarily removed or 

propped open. 

 (5) The test subject shall be trained to hold his or her breath for at least 20 seconds. 

 (6) The test subject shall don the test respirator without any assistance from the individual 

who conducts the CNP fit test. 

 (7) The QNFT protocol shall be followed according to section I. C. 1. of this appendix with an 

exception for the CNP test exercises. 
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(b) CNP Test Exercises. 

 (1) Normal breathing. In a normal standing position, without talking, the subject shall breathe 

normally for 1 minute. After the normal breathing exercise, the subject needs to hold head 

straight ahead and hold his or her breath for 10 seconds during the test measurement. 

 (2) Deep breathing. In a normal standing position, the subject shall breathe slowly and 

deeply for 1 minute, being careful not to hyperventilate. After the deep breathing exercise, the 

subject shall hold his or her head straight ahead and hold his or her breath for 10 seconds 

during test measurement. 

 (3)Turning head side to side. Standing in place, the subject shall slowly turn his or her head 

from side to side between the extreme positions on each side for 1 minute. The head shall be 

held at each extreme momentarily so the subject can inhale at each side. After the turning 

head side to side exercise, the subject needs to hold head full left and hold his or her breath 

for 10 seconds during test measurement. Next, the subject needs to hold head full right and 

hold his or her breath for 10 seconds during test measurement. 

 (4) Moving head up and down. Standing in place, the subject shall slowly move his or her 

head up and down for 1 minute. The subject shall be instructed to inhale in the up position 

(i.e., when looking toward the ceiling). After the moving head up and down exercise, the 

subject shall hold his or her head full up and hold his or her breath for 10 seconds during test 

measurement. Next, the subject shall hold his or her head full down and hold his or her 

breath for 10 seconds during test measurement. 

 (5) Talking. The subject shall talk out loud slowly and loud enough so as to be heard clearly 

by the test conductor. The subject can read from a prepared text such as the Rainbow 

Passage, count backward from 100, or recite a memorized poem or song for 1 minute. After 

the talking exercise, the subject shall hold his or her head straight ahead and hold his or her 

breath for 10 seconds during the test measurement. 

 (6) Grimace. The test subject shall grimace by smiling or frowning for 15 seconds. 

 (7) Bending Over. The test subject shall bend at the waist as if he or she were to touch his or 

her toes for 1 minute. Jogging in place shall be substituted for this exercise in those test 

environments such as shroud-type QNFT units that prohibit bending at the waist. After the 

bending over exercise, the subject shall hold his or her head straight ahead and hold his or 

her breath for 10 seconds during the test measurement. 

 (8) Normal Breathing. The test subject shall remove and re-don the respirator within a oneminute period. Then, in a normal standing position, without talking, the subject shall breathe 

normally for 1 minute. After the normal breathing exercise, the subject shall hold his or her 

head straight ahead and hold his or her breath for 10 seconds during the test measurement. 

After the test exercises, the test subject shall be questioned by the test conductor regarding 

the comfort of the respirator upon completion of the protocol. If it has become unacceptable, 

another model of a respirator shall be tried. 

(c) CNP Test Instrument. 
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 (1) The test instrument shall have an effective audio warning device when the test subject 

fails to hold his or her breath during the test. The test shall be terminated whenever the test 

subject failed to hold his or her breath. The test subject may be refitted and retested. 

 (2) A record of the test shall be kept on file, assuming the fit test was successful. The record 

must contain the test subject's name; overall fit factor; make, model, style and size of 

respirator used; and date tested. 

Part II. New Fit Test Protocols

A. Any person may submit to OSHA an application for approval of a new fit test protocol. If the 

application meets the following criteria, OSHA will initiate a rulemaking proceeding under section 

6(b)(7) of the OSH Act to determine whether to list the new protocol as an approved protocol in this 

Appendix A. 

B. The application must include a detailed description of the proposed new fit test protocol. This 

application must be supported by either: 

1. A test report prepared by an independent government research laboratory (e.g., Lawrence 

Livermore National Laboratory, Los Alamos National Laboratory, the National Institute for Standards 

and Technology) stating that the laboratory has tested the protocol and had found it to be accurate 

and reliable; or 

2. An article that has been published in a peer-reviewed industrial hygiene journal describing the 

protocol and explaining how test data support the protocol's accuracy and reliability. 

C. If OSHA determines that additional information is required before the Agency commences a 

rulemaking proceeding under this section, OSHA will so notify the applicant and afford the applicant 

the opportunity to submit the supplemental information. Initiation of a rulemaking proceeding will be 

deferred until OSHA has received and evaluated the supplemental information. 
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APPENDIX B-1 TO §1910.134: USER SEAL CHECK PROCEDURES (MANDATORY)

The individual who uses a tight-fitting respirator is to perform a user seal check to ensure that an 

adequate seal is achieved each time the respirator is put on. Either the positive and negative 

pressure checks listed in this appendix, or the respirator manufacturer's recommended user seal 

check method shall be used. User seal checks are not substitutes for qualitative or quantitative fit 

tests. 

I. Facepiece Positive and/or Negative Pressure Checks

A. Positive pressure check. Close off the exhalation valve and exhale gently into the facepiece. The 

face fit is considered satisfactory if a slight positive pressure can be built up inside the facepiece 

without any evidence of outward leakage of air at the seal. For most respirators this method of leak 

testing requires the wearer to first remove the exhalation valve cover before closing off the 

exhalation valve and then carefully replacing it after the test. 

B. Negative pressure check. Close off the inlet opening of the canister or cartridge(s) by covering 

with the palm of the hand(s) or by replacing the filter seal(s), inhale gently so that the facepiece 

collapses slightly, and hold the breath for ten seconds. The design of the inlet opening of some 

cartridges cannot be effectively covered with the palm of the hand. The test can be performed by 

covering the inlet opening of the cartridge with a thin latex or nitrile glove. If the facepiece remains in 

its slightly collapsed condition and no inward leakage of air is detected, the tightness of the 

respirator is considered satisfactory. 

II. Manufacturer's Recommended User Seal Check Procedures

The respirator manufacturer's recommended procedures for performing a user seal check may be 

used instead of the positive and/or negative pressure check procedures provided that the employer 

demonstrates that the manufacturer's procedures are equally effective. 
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APPENDIX B-2 TO §1910.134: RESPIRATOR CLEANING PROCEDURES 

(MANDATORY)

These procedures are provided for employer use when cleaning respirators. They are general in 

nature, and the employer as an alternative may use the cleaning recommendations provided by the 

manufacturer of the respirators used by their employees, provided such procedures are as effective 

as those listed here in Appendix B-2. Equivalent effectiveness simply means that the procedures 

used must accomplish the objectives set forth in Appendix B-2, i.e., must ensure that the respirator 

is properly cleaned and disinfected in a manner that prevents damage to the respirator and does not 

cause harm to the user. 

I. Procedures for Cleaning Respirators

A. Remove filters, cartridges, or canisters. Disassemble facepieces by removing speaking 

diaphragms, demand and pressure-demand valve assemblies, hoses, or any components 

recommended by the manufacturer. Discard or repair any defective parts. 

B. Wash components in warm (43 °C [110 °F] maximum) water with a mild detergent or with a 

cleaner recommended by the manufacturer. A stiff bristle (not wire) brush may be used to facilitate 

the removal of dirt. 

C. Rinse components thoroughly in clean, warm (43 °C [110 °F] maximum), preferably running 

water. Drain. 

D. When the cleaner used does not contain a disinfecting agent, respirator components should be 

immersed for two minutes in one of the following: 

1. Hypochlorite solution (50 ppm of chlorine) made by adding approximately one milliliter of laundry 

bleach to one liter of water at 43 °C (110 °F); or, 

2. Aqueous solution of iodine (50 ppm iodine) made by adding approximately 0.8 milliliters of 

tincture of iodine (6-8 grams ammonium and/or potassium iodide/100 cc of 45% alcohol) to one liter 

of water at 43 °C (110 °F); or, 

3. Other commercially available cleansers of equivalent disinfectant quality when used as directed, if 

their use is recommended or approved by the respirator manufacturer. 

E. Rinse components thoroughly in clean, warm (43 °C [110 °F] maximum), preferably running 

water. Drain. The importance of thorough rinsing cannot be overemphasized. Detergents or 

disinfectants that dry on facepieces may result in dermatitis. In addition, some disinfectants may 

cause deterioration of rubber or corrosion of metal parts if not completely removed. 

F. Components should be hand-dried with a clean lint-free cloth or air-dried. 

G. Reassemble facepiece, replacing filters, cartridges, and canisters where necessary. 

H. Test the respirator to ensure that all components work properly. 
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APPENDIX C TO §1910.134: OSHA RESPIRATOR MEDICAL EVALUATION 

QUESTIONNAIRE (MANDATORY)

To the employer: Answers to questions in Section 1, and to question 9 in Section 2 of Part A, do not 

require a medical examination. 

To the employee: 

Can you read (circle one): Yes/No 

Your employer must allow you to answer this questionnaire during normal working hours, or at a 

time and place that is convenient to you. To maintain your confidentiality, your employer or 

supervisor must not look at or review your answers, and your employer must tell you how to deliver 

or send this questionnaire to the health care professional who will review it. 

Part A. Section 1. (Mandatory) The following information must be provided by every employee who 

has been selected to use any type of respirator (please print). 

1. Today's date:_____ 

2. Your name:___________________________________ 

3. Your age (to nearest year):_____ 

4. Sex (circle one): Male/Female 

5. Your height: __ft. __in. 

6. Your weight: __ lbs. 

7. Your job title:____________________________________ 

8. A phone number where you can be reached by the health care professional who reviews this 

questionnaire (include the Area Code): ___________________________________ 

9. The best time to phone you at this number: ______________________ 

10. Has your employer told you how to contact the health care professional who will review this 

questionnaire (circle one): Yes/No 

11. Check the type of respirator you will use (you can check more than one category): 

 a. ___ N, R, or P disposable respirator (filter-mask, non-cartridge type only). 

b. ___ Other type (for example, half- or full-facepiece type, powered-air purifying, supplied-air, 

self-contained breathing apparatus). 
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12. Have you worn a respirator (circle one): Yes/No 

 If "yes," what type(s):___________________________________________________ 

Part A. Section 2. (Mandatory) Questions 1 through 9 below must be answered by every employee 

who has been selected to use any type of respirator (please circle "yes" or "no"). 

1. Do you currently smoke tobacco, or have you smoked tobacco in the last month: Yes/No 

2. Have you ever had any of the following conditions? 

 a. Seizures (fits): Yes/No 

 b. Diabetes (sugar disease): Yes/No 

 c. Allergic reactions that interfere with your breathing: Yes/No 

 d. Claustrophobia (fear of closed-in places): Yes/No 

 e. Trouble smelling odors: Yes/No 

3. Have you ever had any of the following pulmonary or lung problems? 

 a. Asbestosis: Yes/No 

 b. Asthma: Yes/No 

 c. Chronic bronchitis: Yes/No 

 d. Emphysema: Yes/No 

 e. Pneumonia: Yes/No 

 f. Tuberculosis: Yes/No 

 g. Silicosis: Yes/No 

 h. Pneumothorax (collapsed lung): Yes/No 

 i. Lung cancer: Yes/No 

 j. Broken ribs: Yes/No 

 k. Any chest injuries or surgeries: Yes/No 

 l. Any other lung problem that you've been told about: Yes/No 
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4. Do you currently have any of the following symptoms of pulmonary or lung illness? 

 a. Shortness of breath: Yes/No 

b. Shortness of breath when walking fast on level ground or walking up a slight hill or incline: 

Yes/No 

c. Shortness of breath when walking with other people at an ordinary pace on level ground: 

Yes/No 

 d. Have to stop for breath when walking at your own pace on level ground: Yes/No 

 e. Shortness of breath when washing or dressing yourself: Yes/No 

 f. Shortness of breath that interferes with your job: Yes/No 

 g. Coughing that produces phlegm (thick sputum): Yes/No 

 h. Coughing that wakes you early in the morning: Yes/No 

 i. Coughing that occurs mostly when you are lying down: Yes/No 

 j. Coughing up blood in the last month: Yes/No 

 k. Wheezing: Yes/No 

 l. Wheezing that interferes with your job: Yes/No 

 m. Chest pain when you breathe deeply: Yes/No 

 n. Any other symptoms that you think may be related to lung problems: Yes/No 

5. Have you ever had any of the following cardiovascular or heart problems? 

 a. Heart attack: Yes/No 

 b. Stroke: Yes/No 

 c. Angina: Yes/No 

 d. Heart failure: Yes/No 

 e. Swelling in your legs or feet (not caused by walking): Yes/No 

 f. Heart arrhythmia (heart beating irregularly): Yes/No 

 g. High blood pressure: Yes/No 
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 h. Any other heart problem that you've been told about: Yes/No 

6. Have you ever had any of the following cardiovascular or heart symptoms? 

 a. Frequent pain or tightness in your chest: Yes/No 

 b. Pain or tightness in your chest during physical activity: Yes/No 

 c. Pain or tightness in your chest that interferes with your job: Yes/No 

 d. In the past two years, have you noticed your heart skipping or missing a beat: Yes/No 

 e. Heartburn or indigestion that is not related to eating: Yes/No 

 f. Any other symptoms that you think may be related to heart or circulation problems: Yes/No 

7. Do you currently take medication for any of the following problems? 

 a. Breathing or lung problems: Yes/No 

 b. Heart trouble: Yes/No 

 c. Blood pressure: Yes/No 

 d. Seizures (fits): Yes/No 

8. If you've used a respirator, have you ever had any of the following problems? (If you've never 

used a respirator, check the following space and go to question 9:) 

 a. Eye irritation: Yes/No 

 b. Skin allergies or rashes: Yes/No 

 c. Anxiety: Yes/No 

 d. General weakness or fatigue: Yes/No 

 e. Any other problem that interferes with your use of a respirator: Yes/No 

9. Would you like to talk to the health care professional who will review this questionnaire about your 

answers to this questionnaire: Yes/No 
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Questions 10 to 15 below must be answered by every employee who has been selected to use 

either a full-facepiece respirator or a self-contained breathing apparatus (SCBA). For employees 

who have been selected to use other types of respirators, answering these questions is voluntary. 

10. Have you ever lost vision in either eye (temporarily or permanently): Yes/No 

11. Do you currently have any of the following vision problems? 

 a. Wear contact lenses: Yes/No 

 b. Wear glasses: Yes/No 

 c. Color blind: Yes/No 

 d. Any other eye or vision problem: Yes/No 

12. Have you ever had an injury to your ears, including a broken ear drum: Yes/No 

13. Do you currently have any of the following hearing problems? 

 a. Difficulty hearing: Yes/No 

 b. Wear a hearing aid: Yes/No 

 c. Any other hearing or ear problem: Yes/No 

14. Have you ever had a back injury: Yes/No 

15. Do you currently have any of the following musculoskeletal problems? 

 a. Weakness in any of your arms, hands, legs, or feet: Yes/No 

 b. Back pain: Yes/No 

 c. Difficulty fully moving your arms and legs: Yes/No 

 d. Pain or stiffness when you lean forward or backward at the waist: Yes/No 

 e. Difficulty fully moving your head up or down: Yes/No 

 f. Difficulty fully moving your head side to side: Yes/No 

 g. Difficulty bending at your knees: Yes/No 

 h. Difficulty squatting to the ground: Yes/No 

 i. Climbing a flight of stairs or a ladder carrying more than 25 lbs: Yes/No 
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 j. Any other muscle or skeletal problem that interferes with using a respirator: Yes/No 

Part B Any of the following questions, and other questions not listed, may be added to the 

questionnaire at the discretion of the health care professional who will review the questionnaire. 

1. In your present job, are you working at high altitudes (over 5,000 feet) or in a place that has lower 

than normal amounts of oxygen: Yes/No 

 If "yes," do you have feelings of dizziness, shortness of breath, pounding in your chest, or other 

symptoms when you're working under these conditions: Yes/No 

2. At work or at home, have you ever been exposed to hazardous solvents, hazardous airborne 

chemicals (e.g., gases, fumes, or dust), or have you come into skin contact with hazardous 

chemicals: Yes/No 

 If "yes," name the chemicals if you know them:____________________________________ 

3. Have you ever worked with any of the materials, or under any of the conditions, listed below: 

 a. Asbestos: Yes/No 

 b. Silica (e.g., in sandblasting): Yes/No 

 c. Tungsten/cobalt (e.g., grinding or welding this material): Yes/No 

 d. Beryllium: Yes/No 

 e. Aluminum: Yes/No 

 f. Coal (for example, mining): Yes/No 

 g. Iron: Yes/No 

 h. Tin: Yes/No 

 i. Dusty environments: Yes/No 

 j. Any other hazardous exposures: Yes/No 

 If "yes," describe these exposures:_______________________________________________ 

 

 __________________________________________________________________________ 

4. List any second jobs or side businesses you have:___________________________________ 
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5. List your previous occupations:__________________________________________________ 

6. List your current and previous hobbies:____________________________________________ 

7. Have you been in the military services? Yes/No 

 If "yes," were you exposed to biological or chemical agents (either in training or combat): Yes/No 

8. Have you ever worked on a HAZMAT team? Yes/No 

9. Other than medications for breathing and lung problems, heart trouble, blood pressure, and 

seizures mentioned earlier in this questionnaire, are you taking any other medications for any 

reason (including over-the-counter medications): Yes/No 

 If "yes," name the medications if you know them:__________________________________ 

10. Will you be using any of the following items with your respirator(s)? 

 a. HEPA Filters: Yes/No 

 b. Canisters (for example, gas masks): Yes/No 

 c. Cartridges: Yes/No 

11. How often are you expected to use the respirator(s) (circle "yes" or "no" for all answers that 

apply to you)?: 

 a. Escape only (no rescue): Yes/No 

 b. Emergency rescue only: Yes/No 

 c. Less than 5 hours per week: Yes/No 

 d. Less than 2 hours per day: Yes/No 

 e. 2 to 4 hours per day: Yes/No 

 f. Over 4 hours per day: Yes/No 

12. During the period you are using the respirator(s), is your work effort: 

 a. Light (less than 200 kcal per hour): Yes/No 

 If "yes," how long does this period last during the average shift:______hrs.______mins. 

Examples of a light work effort are sitting while writing, typing, drafting, or performing light assembly 

work; or standing while operating a drill press (1-3 lbs.) or controlling machines. 
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 b. Moderate (200 to 350 kcal per hour): Yes/No 

 If "yes," how long does this period last during the average shift:______hrs.______mins. 

Examples of moderate work effort are sitting while nailing or filing; driving a truck or bus in urban 

traffic; standing while drilling, nailing, performing assembly work, or transferring a moderate load 

(about 35 lbs.) at trunk level; walking on a level surface about 2 mph or down a 5-degree grade 

about 3 mph; or pushing a wheelbarrow with a heavy load (about 100 lbs.) on a level surface. 

 c. Heavy (above 350 kcal per hour): Yes/No 

 If "yes," how long does this period last during the average shift:______hrs.______mins. 

Examples of heavy work are lifting a heavy load (about 50 lbs.) from the floor to your waist or 

shoulder; working on a loading dock; shoveling; standing while bricklaying or chipping castings; 

walking up an 8-degree grade about 2 mph; climbing stairs with a heavy load (about 50 lbs.). 

13. Will you be wearing protective clothing and/or equipment (other than the respirator) when you're 

using your respirator: Yes/No If "yes," describe this protective clothing and/or equipment:_____ 

______________________________________________________________________________ 

14. Will you be working under hot conditions (temperature exceeding 77 °F): Yes/No 

15. Will you be working under humid conditions: Yes/No 

16. Describe the work you'll be doing while you're using your respirator(s): ___________________ 

______________________________________________________________________________ 

______________________________________________________________________________ 

17. Describe any special or hazardous conditions you might encounter when you're using your 

respirator(s) (for example, confined spaces, life-threatening gases): ________________________ 

______________________________________________________________________________ 

______________________________________________________________________________ 

18. Provide the following information, if you know it, for each toxic substance that you'll be exposed 

to when you're using your respirator(s): 

 Name of the first toxic substance:_____________________________ 

 Estimated maximum exposure level per shift:____________________ 
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 Duration of exposure per shift________________________________ 

 Name of the second toxic substance:__________________________ 

 Estimated maximum exposure level per shift:____________________ 

 Duration of exposure per shift:_______________________________ 

 Name of the third toxic substance:____________________________ 

 Estimated maximum exposure level per shift:___________________ 

 Duration of exposure per shift:_______________________________ 

 The name of any other toxic substances that you'll be exposed to while using your respirator: 

 _________________________________________________________________________ 

 _________________________________________________________________________ 

19. Describe any special responsibilities you'll have while using your respirator(s) that may affect the 

safety and well-being of others (for example, rescue, security): __________________________ 

 __________________________________________________________________________ 

 
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APPENDIX D TO §1910.134 (MANDATORY) INFORMATION FOR EMPLOYEES USING 

RESPIRATORS WHEN NOT REQUIRED UNDER THE STANDARD

Respirators are an effective method of protection against designated hazards when properly 

selected and worn. Respirator use is encouraged, even when exposures are below the exposure 

limit, to provide an additional level of comfort and protection for workers. However, if a respirator is 

used improperly or not kept clean, the respirator itself can become a hazard to the worker. 

Sometimes, workers may wear respirators to avoid exposures to hazards, even if the amount of 

hazardous substance does not exceed the limits set by OSHA standards. If your employer provides 

respirators for your voluntary use, of if you provide your own respirator, you need to take certain 

precautions to be sure that the respirator itself does not present a hazard. 

You should do the following: 

1. Read and heed all instructions provided by the manufacturer on use, maintenance, cleaning and 

care, and warnings regarding the respirators limitations. 

2. Choose respirators certified for use to protect against the contaminant of concern. NIOSH, the 

National Institute for Occupational Safety and Health of the U.S. Department of Health and Human 

Services, certifies respirators. A label or statement of certification should appear on the respirator or 

respirator packaging. It will tell you what the respirator is designed for and how much it will protect 

you. 

3. Do not wear your respirator into atmospheres containing contaminants for which your respirator is 

not designed to protect against. For example, a respirator designed to filter dust particles will not 

protect you against gases, vapors, or very small solid particles of fumes or smoke. 

4. Keep track of your respirator so that you do not mistakenly use someone else's respirator. 

[63 FR 1270, Jan. 8, 1998; 63 FR 20098, 20099, Apr. 23, 1998] 
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SECTION E 

DRAWINGS