| Nachbrennen | afterflaming |
| Nachfüllung (Atemluftflasche) | recharging (breathing air cylinder) |
| Nachsteiger | pressure build-up |
| Nachweis | records |
| Nackenband | neck strap |
| Nackenleder | neck curtain |
| Nahtfestigkeit | seam strength (chemical protective suit) |
| Nasenbügel | nosepiece |
| Nasenklemme | nose clip |
| Natriumchlorid | sodium three chlorite |
| Nebel | mist |
| Negativzeit | negative time |
| Nervengift (Atemgift) | neurotoxin (breathing poison) |
| Nenneinsatzdauer | manufacturer’s design duration |
| Nenngebrauchszeit | nominal working duration |
| Nennschutzfaktor | nominal protection factor |
| Niederdruck | low pressure |
| Niederdruckprüfung | low pressure leak test |
| nitrose Gase | nitrous gases |
| Nitrox | nitrox |
| Nominelle Haltezeit | nominal breakthrough period |
| Nonkonformität | non-conformity |
| Norm | norm, standard |
| Notfallmeldung | emergency report |
| Notifizierte Stelle | Notified Body |
| Notruf | emergency call |
| Notsignal | distress signal |
| Notsignal – akustisches | distress signal, audible |
| Notsignal – pneumatisches | pneumatic distress signal |
| Notsignalempfänger | distress signal receiver |
| Notsignalgeber | distress signal transmitter |
