| 42:1.0.1.7.67.1 | SUBPART A 
 | Subpart A - General Provisions |  | 
| 42:1.0.1.7.67.1.15.1 | SECTION 84.1 
 | 84.1 Purpose. |  | 
| 42:1.0.1.7.67.1.15.2 | SECTION 84.2 
 | 84.2 Definitions. |  | 
| 42:1.0.1.7.67.1.15.3 | SECTION 84.3 
 | 84.3 Respirators for mine rescue or other emergency use in mines. |  | 
| 42:1.0.1.7.67.2 | SUBPART B 
 | Subpart B - Application for Approval |  | 
| 42:1.0.1.7.67.2.15.1 | SECTION 84.10 
 | 84.10 Application procedures. |  | 
| 42:1.0.1.7.67.2.15.2 | SECTION 84.11 
 | 84.11 Contents of application. |  | 
| 42:1.0.1.7.67.2.15.3 | SECTION 84.12 
 | 84.12 Delivery of respirators and components by applicant; requirements. |  | 
| 42:1.0.1.7.67.3 | SUBPART C 
 | Subpart C - Fees |  | 
| 42:1.0.1.7.67.3.15.1 | SECTION 84.20 
 | 84.20 Establishment of fees. |  | 
| 42:1.0.1.7.67.3.15.2 | SECTION 84.21 
 | 84.21 Fee calculation. |  | 
| 42:1.0.1.7.67.3.15.3 | SECTION 84.22 
 | 84.22 Fee administration. |  | 
| 42:1.0.1.7.67.3.15.4 | SECTION 84.23 
 | 84.23 Fee revision. |  | 
| 42:1.0.1.7.67.3.15.5 | SECTION 84.24 
 | 84.24 Authorization for additional examinations, inspections, tests, and fees. |  | 
| 42:1.0.1.7.67.4 | SUBPART D 
 | Subpart D - Approval and Disapproval |  | 
| 42:1.0.1.7.67.4.15.1 | SECTION 84.30 
 | 84.30 Certificates of approval; scope of approval. |  | 
| 42:1.0.1.7.67.4.15.2 | SECTION 84.31 
 | 84.31 Certificates of approval; contents. |  | 
| 42:1.0.1.7.67.4.15.3 | SECTION 84.32 
 | 84.32 Notice of disapproval. |  | 
| 42:1.0.1.7.67.4.15.4 | SECTION 84.33 
 | 84.33 Approval labels and markings; approval of contents; use. |  | 
| 42:1.0.1.7.67.4.15.5 | SECTION 84.34 
 | 84.34 Revocation of certificates of approval. |  | 
| 42:1.0.1.7.67.4.15.6 | SECTION 84.35 
 | 84.35 Changes or modifications of approved respirators; issuance of modification of certificate of approval. |  | 
| 42:1.0.1.7.67.4.15.7 | SECTION 84.36 
 | 84.36 Delivery of changed or modified approved respirator. |  | 
| 42:1.0.1.7.67.5 | SUBPART E 
 | Subpart E - Quality Control |  | 
| 42:1.0.1.7.67.5.15.1 | SECTION 84.40 
 | 84.40 Quality control plans; filing requirements. |  | 
| 42:1.0.1.7.67.5.15.2 | SECTION 84.41 
 | 84.41 Quality control plans; contents. |  | 
| 42:1.0.1.7.67.5.15.3 | SECTION 84.42 
 | 84.42 Proposed quality control plans; approval by the Institute. |  | 
| 42:1.0.1.7.67.5.15.4 | SECTION 84.43 
 | 84.43 Quality control records; review by the Institute; revocation of approval. |  | 
| 42:1.0.1.7.67.6 | SUBPART F 
 | Subpart F - Classification of Approved Respirators; Scope of Approval; Atmospheric Hazards; Service Time |  | 
| 42:1.0.1.7.67.6.15.1 | SECTION 84.50 
 | 84.50 Types of respirators to be approved; scope of approval. |  | 
| 42:1.0.1.7.67.6.15.2 | SECTION 84.51 
 | 84.51 Entry and escape, or escape only; classification. |  | 
| 42:1.0.1.7.67.6.15.3 | SECTION 84.52 
 | 84.52 Respiratory hazards; classification. |  | 
| 42:1.0.1.7.67.6.15.4 | SECTION 84.53 
 | 84.53 Service time; classification. |  | 
| 42:1.0.1.7.67.7 | SUBPART G 
 | Subpart G - General Construction and Performance Requirements |  | 
| 42:1.0.1.7.67.7.15.1 | SECTION 84.60 
 | 84.60 Construction and performance requirements; general. |  | 
| 42:1.0.1.7.67.7.15.2 | SECTION 84.61 
 | 84.61 General construction requirements. |  | 
| 42:1.0.1.7.67.7.15.3 | SECTION 84.62 
 | 84.62 Component parts; minimum requirements. |  | 
| 42:1.0.1.7.67.7.15.4 | SECTION 84.63 
 | 84.63 Test requirements; general. |  | 
| 42:1.0.1.7.67.7.15.5 | SECTION 84.64 
 | 84.64 Pretesting by applicant; approval of test methods. |  | 
| 42:1.0.1.7.67.7.15.6 | SECTION 84.65 
 | 84.65 Conduct of examinations, inspections, and tests by the Institute; assistance by applicant; observers; recorded data; public demonstrations. |  | 
| 42:1.0.1.7.67.7.15.7 | SECTION 84.66 
 | 84.66 Withdrawal of applications. |  | 
| 42:1.0.1.7.67.8 | SUBPART H 
 | Subpart H - Self-Contained Breathing Apparatus |  | 
| 42:1.0.1.7.67.8.15.1 | SECTION 84.70 
 | 84.70 Self-contained breathing apparatus; description. |  | 
| 42:1.0.1.7.67.8.15.2 | SECTION 84.71 
 | 84.71 Self-contained breathing apparatus; required components. |  | 
| 42:1.0.1.7.67.8.15.3 | SECTION 84.72 
 | 84.72 Breathing tubes; minimum requirements. |  | 
| 42:1.0.1.7.67.8.15.4 | SECTION 84.73 
 | 84.73 Harnesses; installation and construction; minimum requirements. |  | 
| 42:1.0.1.7.67.8.15.5 | SECTION 84.74 
 | 84.74 Apparatus containers; minimum requirements. |  | 
| 42:1.0.1.7.67.8.15.6 | SECTION 84.75 
 | 84.75 Half-mask facepieces, full facepieces, mouthpieces; fit; minimum requirements. |  | 
| 42:1.0.1.7.67.8.15.7 | SECTION 84.76 
 | 84.76 Facepieces; eyepieces; minimum requirements. |  | 
| 42:1.0.1.7.67.8.15.8 | SECTION 84.77 
 | 84.77 Inhalation and exhalation valves; minimum requirements. |  | 
| 42:1.0.1.7.67.8.15.9 | SECTION 84.78 
 | 84.78 Head harnesses; minimum requirements. |  | 
| 42:1.0.1.7.67.8.15.10 | SECTION 84.79 
 | 84.79 Breathing gas; minimum requirements. |  | 
| 42:1.0.1.7.67.8.15.11 | SECTION 84.80 
 | 84.80 Interchangeability of oxygen and air prohibited. |  | 
| 42:1.0.1.7.67.8.15.12 | SECTION 84.81 
 | 84.81 Compressed breathing gas and liquefied breathing gas containers; minimum requirements. |  | 
| 42:1.0.1.7.67.8.15.13 | SECTION 84.82 
 | 84.82 Gas pressure gages; minimum requirements. |  | 
| 42:1.0.1.7.67.8.15.14 | SECTION 84.83 
 | 84.83 Timers; elapsed time indicators; remaining service life indicators; minimum requirements. |  | 
| 42:1.0.1.7.67.8.15.15 | SECTION 84.84 
 | 84.84 Hand-operated valves; minimum requirements. |  | 
| 42:1.0.1.7.67.8.15.16 | SECTION 84.85 
 | 84.85 Breathing bags; minimum requirements. |  | 
| 42:1.0.1.7.67.8.15.17 | SECTION 84.86 
 | 84.86 Component parts exposed to oxygen pressures; minimum requirements. |  | 
| 42:1.0.1.7.67.8.15.18 | SECTION 84.87 
 | 84.87 Compressed gas filters; minimum requirements. |  | 
| 42:1.0.1.7.67.8.15.19 | SECTION 84.88 
 | 84.88 Breathing bag test. |  | 
| 42:1.0.1.7.67.8.15.20 | SECTION 84.89 
 | 84.89 Weight requirement. |  | 
| 42:1.0.1.7.67.8.15.21 | SECTION 84.90 
 | 84.90 Breathing resistance test; inhalation. |  | 
| 42:1.0.1.7.67.8.15.22 | SECTION 84.91 
 | 84.91 Breathing resistance test; exhalation. |  | 
| 42:1.0.1.7.67.8.15.23 | SECTION 84.92 
 | 84.92 Exhalation valve leakage test. |  | 
| 42:1.0.1.7.67.8.15.24 | SECTION 84.93 
 | 84.93 Gas flow test; open-circuit apparatus. |  | 
| 42:1.0.1.7.67.8.15.25 | SECTION 84.94 
 | 84.94 Gas flow test; closed-circuit apparatus. |  | 
| 42:1.0.1.7.67.8.15.26 | SECTION 84.95 
 | 84.95 Service time test; open-circuit apparatus. |  | 
| 42:1.0.1.7.67.8.15.27 | SECTION 84.96 
 | 84.96 Service time test; closed-circuit apparatus. |  | 
| 42:1.0.1.7.67.8.15.28 | SECTION 84.97 
 | 84.97 Test for carbon dioxide in inspired gas; open- and closed-circuit apparatus; maximum allowable limits. |  | 
| 42:1.0.1.7.67.8.15.29 | SECTION 84.98 
 | 84.98 Tests during low temperature operation. |  | 
| 42:1.0.1.7.67.8.15.30 | SECTION 84.99 
 | 84.99 Man tests; testing conditions; general requirements. |  | 
| 42:1.0.1.7.67.8.15.31 | SECTION 84.100 
 | 84.100 Man tests 1, 2, 3, and 4; requirements. |  | 
| 42:1.0.1.7.67.8.15.32 | SECTION 84.101 
 | 84.101 Man test 5; requirements. |  | 
| 42:1.0.1.7.67.8.15.33 | SECTION 84.102 
 | 84.102 Man test 6; requirements. |  | 
| 42:1.0.1.7.67.8.15.34 | SECTION 84.103 
 | 84.103 Man tests; performance requirements. |  | 
| 42:1.0.1.7.67.8.15.35 | SECTION 84.104 
 | 84.104 Gas tightness test; minimum requirements. |  | 
| 42:1.0.1.7.67.9 | SUBPART 0 
 |  |  | 
| 42:1.0.1.7.67.10 | SUBPART I 
 | Subpart I - Gas Masks |  | 
| 42:1.0.1.7.67.10.15.1 | SECTION 84.110 
 | 84.110 Gas masks; description. |  | 
| 42:1.0.1.7.67.10.15.1.17 | APPENDIX 
 | Tables to Subpart H of Part 84 |  | 
| 42:1.0.1.7.67.10.15.2 | SECTION 84.111 
 | 84.111 Gas masks; required components. |  | 
| 42:1.0.1.7.67.10.15.3 | SECTION 84.112 
 | 84.112 Canisters and cartridges in parallel; resistance requirements. |  | 
| 42:1.0.1.7.67.10.15.4 | SECTION 84.113 
 | 84.113 Canisters and cartridges; color and markings; requirements. |  | 
| 42:1.0.1.7.67.10.15.5 | SECTION 84.114 
 | 84.114 Filters used with canisters and cartridges; location; replacement. |  | 
| 42:1.0.1.7.67.10.15.6 | SECTION 84.115 
 | 84.115 Breathing tubes; minimum requirements. |  | 
| 42:1.0.1.7.67.10.15.7 | SECTION 84.116 
 | 84.116 Harnesses; installation and construction; minimum requirements. |  | 
| 42:1.0.1.7.67.10.15.8 | SECTION 84.117 
 | 84.117 Gas mask containers; minimum requirements. |  | 
| 42:1.0.1.7.67.10.15.9 | SECTION 84.118 
 | 84.118 Half-mask facepieces, full facepieces, and mouthpieces; fit; minimum requirements. |  | 
| 42:1.0.1.7.67.10.15.10 | SECTION 84.119 
 | 84.119 Facepieces; eyepieces; minimum requirements. |  | 
| 42:1.0.1.7.67.10.15.11 | SECTION 84.120 
 | 84.120 Inhalation and exhalation valves; minimum requirements. |  | 
| 42:1.0.1.7.67.10.15.12 | SECTION 84.121 
 | 84.121 Head harnesses; minimum requirements. |  | 
| 42:1.0.1.7.67.10.15.13 | SECTION 84.122 
 | 84.122 Breathing resistance test; minimum requirements. |  | 
| 42:1.0.1.7.67.10.15.14 | SECTION 84.123 
 | 84.123 Exhalation valve leakage test. |  | 
| 42:1.0.1.7.67.10.15.15 | SECTION 84.124 
 | 84.124 Facepiece tests; minimum requirements. |  | 
| 42:1.0.1.7.67.10.15.16 | SECTION 84.125 
 | 84.125 Particulate tests; canisters containing particulate filters; minimum requirements. |  | 
| 42:1.0.1.7.67.10.15.17 | SECTION 84.126 
 | 84.126 Canister bench tests; minimum requirements. |  | 
| 42:1.0.1.7.67.10.15.18.18 | APPENDIX 
 | Tables to Subpart I of Part 84 |  | 
| 42:1.0.1.7.67.11 | SUBPART J 
 | Subpart J - Supplied-Air Respirators |  | 
| 42:1.0.1.7.67.11.15.1 | SECTION 84.130 
 | 84.130 Supplied-air respirators; description. |  | 
| 42:1.0.1.7.67.11.15.2 | SECTION 84.131 
 | 84.131 Supplied-air respirators; required components. |  | 
| 42:1.0.1.7.67.11.15.3 | SECTION 84.132 
 | 84.132 Breathing tubes; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.4 | SECTION 84.133 
 | 84.133 Harnesses; installation and construction; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.5 | SECTION 84.134 
 | 84.134 Respirator containers; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.6 | SECTION 84.135 
 | 84.135 Half-mask facepieces, full facepieces, hoods, and helmets; fit; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.7 | SECTION 84.136 
 | 84.136 Facepieces, hoods, and helmets; eyepieces; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.8 | SECTION 84.137 
 | 84.137 Inhalation and exhalation valves; check valves; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.9 | SECTION 84.138 
 | 84.138 Head harnesses; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.10 | SECTION 84.139 
 | 84.139 Head and neck protection; supplied-air respirators; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.11 | SECTION 84.140 
 | 84.140 Air velocity and noise levels; hoods and helmets; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.12 | SECTION 84.141 
 | 84.141 Breathing gas; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.13 | SECTION 84.142 
 | 84.142 Air supply source; hand-operated or motor driven air blowers; Type A supplied-air respirators; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.14 | SECTION 84.143 
 | 84.143 Terminal fittings or chambers; Type B supplied-air respirators; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.15 | SECTION 84.144 
 | 84.144 Hand-operated blower test; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.16 | SECTION 84.145 
 | 84.145 Motor-operated blower test; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.17 | SECTION 84.146 
 | 84.146 Method of measuring the power and torque required to operate blowers. |  | 
| 42:1.0.1.7.67.11.15.18 | SECTION 84.147 
 | 84.147 Type B supplied-air respirator; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.19 | SECTION 84.148 
 | 84.148 Type C supplied-air respirator, continuous flow class; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.20 | SECTION 84.149 
 | 84.149 Type C supplied-air respirator, demand and pressure demand class; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.21 | SECTION 84.150 
 | 84.150 Air-supply line tests; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.22 | SECTION 84.151 
 | 84.151 Harness test; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.23 | SECTION 84.152 
 | 84.152 Breathing tube test; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.24 | SECTION 84.153 
 | 84.153 Airflow resistance test, Type A and Type AE supplied-air respirators; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.25 | SECTION 84.154 
 | 84.154 Airflow resistance test; Type B and Type BE supplied-air respirators; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.26 | SECTION 84.155 
 | 84.155 Airflow resistance test; Type C supplied-air respirator, continuous flow class and Type CE supplied-air respirator; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.27 | SECTION 84.156 
 | 84.156 Airflow resistance test; Type C supplied-air respirator, demand class; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.28 | SECTION 84.157 
 | 84.157 Airflow resistance test; Type C supplied-air respirator, pressure-demand class; minimum requirements. |  | 
| 42:1.0.1.7.67.11.15.29 | SECTION 84.158 
 | 84.158 Exhalation valve leakage test. |  | 
| 42:1.0.1.7.67.11.15.30 | SECTION 84.159 
 | 84.159 Man tests for gases and vapors; supplied-air respirators; general performance requirements. |  | 
| 42:1.0.1.7.67.11.15.31 | SECTION 84.160 
 | 84.160 Man test for gases and vapors; Type A and Type AE respirators; test requirements. |  | 
| 42:1.0.1.7.67.11.15.32 | SECTION 84.161 
 | 84.161 Man test for gases and vapors; Type B and Type BE respirators; test requirements. |  | 
| 42:1.0.1.7.67.11.15.33 | SECTION 84.162 
 | 84.162 Man test for gases and vapors; Type C respirators, continuous-flow class and Type CE supplied-air respirators; test requirements. |  | 
| 42:1.0.1.7.67.11.15.34 | SECTION 84.163 
 | 84.163 Man test for gases and vapors; Type C supplied-air respirators, demand and pressure-demand classes; test requirements. |  | 
| 42:1.0.1.7.67.11.15.35.19 | APPENDIX 
 | Table to Subpart J of Part 84 |  | 
| 42:1.0.1.7.67.12 | SUBPART K 
 | Subpart K - Air-Purifying Particulate Respirators |  | 
| 42:1.0.1.7.67.12.15.1 | SECTION 84.170 
 | 84.170 Air-purifying particulate respirators; description. |  | 
| 42:1.0.1.7.67.12.15.2 | SECTION 84.171 
 | 84.171 Required components and attributes. |  | 
| 42:1.0.1.7.67.12.15.3 | SECTION 84.172 
 | 84.172 Airflow resistance test. |  | 
| 42:1.0.1.7.67.12.15.4 | SECTION 84.173 
 | 84.173 Exhalation valve leakage test. |  | 
| 42:1.0.1.7.67.12.15.5 | SECTION 84.174 
 | 84.174 Filter efficiency level determination test - non-powered series N, R, and P filtration. |  | 
| 42:1.0.1.7.67.12.15.6 | SECTION 84.175 
 | 84.175 Instantaneous filter efficiency level determination test - PAPR series HE, PAPR100-N, and PAPR100-P filtration. |  | 
| 42:1.0.1.7.67.12.15.7 | SECTION 84.176 
 | 84.176 Fit test - PAPR classes HE and PAPR100. |  | 
| 42:1.0.1.7.67.12.15.8 | SECTION 84.177 
 | 84.177 Total noise level test - PAPR classes HE and PAPR100. |  | 
| 42:1.0.1.7.67.12.15.9 | SECTION 84.178 
 | 84.178 Breath response type, airflow resistance test - PAPR classes HE and PAPR100. |  | 
| 42:1.0.1.7.67.12.15.10 | SECTION 84.179 
 | 84.179 Silica dust loading test - PAPR series HE filtration. |  | 
| 42:1.0.1.7.67.12.15.11 | SECTION 84.180 
 | 84.180 Particulate loading test - PAPR series PAPR100-N and PAPR100-P filtration. |  | 
| 42:1.0.1.7.67.12.15.12 | SECTION 84.181 
 | 84.181 Communication performance test - PAPR class PAPR100. |  | 
| 42:1.0.1.7.67.13 | SUBPART L 
 | Subpart L - Chemical Cartridge Respirators |  | 
| 42:1.0.1.7.67.13.15.1 | SECTION 84.190 
 | 84.190 Chemical cartridge respirators: description. |  | 
| 42:1.0.1.7.67.13.15.2 | SECTION 84.191 
 | 84.191 Chemical cartridge respirators; required components. |  | 
| 42:1.0.1.7.67.13.15.3 | SECTION 84.192 
 | 84.192 Cartridges in parallel; resistance requirements. |  | 
| 42:1.0.1.7.67.13.15.4 | SECTION 84.193 
 | 84.193 Cartridges; color and markings; requirements. |  | 
| 42:1.0.1.7.67.13.15.5 | SECTION 84.194 
 | 84.194 Filters used with chemical cartridges; location; replacement. |  | 
| 42:1.0.1.7.67.13.15.6 | SECTION 84.195 
 | 84.195 Breathing tubes; minimum requirements. |  | 
| 42:1.0.1.7.67.13.15.7 | SECTION 84.196 
 | 84.196 Harnesses; installation and construction; minimum requirements. |  | 
| 42:1.0.1.7.67.13.15.8 | SECTION 84.197 
 | 84.197 Respirator containers; minimum requirements. |  | 
| 42:1.0.1.7.67.13.15.9 | SECTION 84.198 
 | 84.198 Half-mask facepieces, full facepieces, mouthpieces, hoods, and helmets; fit; minimum requirements. |  | 
| 42:1.0.1.7.67.13.15.10 | SECTION 84.199 
 | 84.199 Facepieces, hoods, and helmets; eyepieces; minimum requirements. |  | 
| 42:1.0.1.7.67.13.15.11 | SECTION 84.200 
 | 84.200 Inhalation and exhalation valves; minimum requirements. |  | 
| 42:1.0.1.7.67.13.15.12 | SECTION 84.201 
 | 84.201 Head harnesses; minimum requirements. |  | 
| 42:1.0.1.7.67.13.15.13 | SECTION 84.202 
 | 84.202 Air velocity and noise levels; hoods and helmets; minimum requirements. |  | 
| 42:1.0.1.7.67.13.15.14 | SECTION 84.203 
 | 84.203 Breathing resistance test; minimum requirements. |  | 
| 42:1.0.1.7.67.13.15.15 | SECTION 84.204 
 | 84.204 Exhalation valve leakage test; minimum requirements. |  | 
| 42:1.0.1.7.67.13.15.16 | SECTION 84.205 
 | 84.205 Facepiece test; minimum requirements. |  | 
| 42:1.0.1.7.67.13.15.17 | SECTION 84.206 
 | 84.206 Particulate tests; respirators with filters; minimum requirements; general. |  | 
| 42:1.0.1.7.67.13.15.18 | SECTION 84.207 
 | 84.207 Bench tests; gas and vapor tests; minimum requirements; general. |  | 
| 42:1.0.1.7.67.13.15.19.20 | APPENDIX 
 | Tables to Subpart L of Part 84 |  | 
| 42:1.0.1.7.67.14 | SUBPART M 
 | Subpart M [Reserved] |  | 
| 42:1.0.1.7.67.15 | SUBPART N 
 | Subpart N - Special Use Respirators |  | 
| 42:1.0.1.7.67.15.15.1 | SECTION 84.250 
 | 84.250 Vinyl chloride respirators; description. |  | 
| 42:1.0.1.7.67.15.15.2 | SECTION 84.251 
 | 84.251 Required components. |  | 
| 42:1.0.1.7.67.15.15.3 | SECTION 84.252 
 | 84.252 Gas masks; requirements and tests. |  | 
| 42:1.0.1.7.67.15.15.4 | SECTION 84.253 
 | 84.253 Chemical-cartridge respirators; requirements and tests. |  | 
| 42:1.0.1.7.67.15.15.5 | SECTION 84.254 
 | 84.254 Powered air-purifying respirators; requirements and tests. |  | 
| 42:1.0.1.7.67.15.15.6 | SECTION 84.255 
 | 84.255 Requirements for end-of-service-life indicator. |  | 
| 42:1.0.1.7.67.15.15.7 | SECTION 84.256 
 | 84.256 Quality control requirements. |  | 
| 42:1.0.1.7.67.15.15.8 | SECTION 84.257 
 | 84.257 Labeling requirements. |  | 
| 42:1.0.1.7.67.16 | SUBPART O 
 | Subpart O - Closed-Circuit Escape Respirators |  | 
| 42:1.0.1.7.67.16.15.1 | SECTION 84.300 
 | 84.300 Closed-circuit escape respirator; description. |  | 
| 42:1.0.1.7.67.16.15.2 | SECTION 84.301 
 | 84.301 Applicability to new and previously approved CCERs. |  | 
| 42:1.0.1.7.67.16.15.3 | SECTION 84.302 
 | 84.302 Required components, attributes, and instructions. |  | 
| 42:1.0.1.7.67.16.15.4 | SECTION 84.303 
 | 84.303 General testing conditions and requirements. |  | 
| 42:1.0.1.7.67.16.15.5 | SECTION 84.304 
 | 84.304 Capacity test requirements. |  | 
| 42:1.0.1.7.67.16.15.6 | SECTION 84.305 
 | 84.305 Performance test requirements. |  | 
| 42:1.0.1.7.67.16.15.7 | SECTION 84.306 
 | 84.306 Wearability test requirements. |  | 
| 42:1.0.1.7.67.16.15.8 | SECTION 84.307 
 | 84.307 Environmental treatments. |  | 
| 42:1.0.1.7.67.16.15.9 | SECTION 84.308 
 | 84.308 Additional testing. |  | 
| 42:1.0.1.7.67.16.15.10 | SECTION 84.309 
 | 84.309 Additional testing and requirements for dockable CCERs. |  | 
| 42:1.0.1.7.67.16.15.11 | SECTION 84.310 
 | 84.310 Post-approval testing. |  | 
| 42:1.0.1.7.67.16.15.12 | SECTION 84.311 
 | 84.311 Registration of CCER units upon purchase. |  | 
| 42:1.0.1.7.67.17 | SUBPART P 
 | Subparts P-JJ [Reserved] |  |