diff --git a/project/src/helpers/ItemHelper.ts b/project/src/helpers/ItemHelper.ts
index d34785b8..2de92170 100644
--- a/project/src/helpers/ItemHelper.ts
+++ b/project/src/helpers/ItemHelper.ts
@@ -854,7 +854,7 @@ class ItemHelper
      */
     public isAttachmentAttached(item: Item): boolean
     {
-        return item.slotId !== "hideout" && item.slotId !== "main" && isNaN(Number(item.slotId));
+        return item.slotId !== "hideout" && item.slotId !== "main" && Number.isNaN(Number(item.slotId));
     }
 
     /**
diff --git a/project/src/helpers/RagfairOfferHelper.ts b/project/src/helpers/RagfairOfferHelper.ts
index 45f2e7d4..6543ad18 100644
--- a/project/src/helpers/RagfairOfferHelper.ts
+++ b/project/src/helpers/RagfairOfferHelper.ts
@@ -297,7 +297,7 @@ export class RagfairOfferHelper
     public increaseProfileRagfairRating(profile: IAkiProfile, amountToIncrementBy: number): void
     {
         profile.characters.pmc.RagfairInfo.isRatingGrowing = true;
-        if (isNaN(amountToIncrementBy))
+        if (Number.isNaN(amountToIncrementBy))
         {
             this.logger.warning(`Unable to increment ragfair rating, value was not a number: ${amountToIncrementBy}`);
 
@@ -595,7 +595,7 @@ export class RagfairOfferHelper
             return false;
         }
 
-        if (isNaN(offer.requirementsCost))
+        if (Number.isNaN(offer.requirementsCost))
         {
             // don't include offers with null or NaN in it
             return false;
diff --git a/project/src/helpers/RagfairSellHelper.ts b/project/src/helpers/RagfairSellHelper.ts
index 43f95f93..12d0ba55 100644
--- a/project/src/helpers/RagfairSellHelper.ts
+++ b/project/src/helpers/RagfairSellHelper.ts
@@ -77,7 +77,7 @@ export class RagfairSellHelper
         const result: SellResult[] = [];
         
         // Value can sometimes be NaN for whatever reason, default to base chance if that happens
-        if (isNaN(sellChancePercent))
+        if (Number.isNaN(sellChancePercent))
         {
             this.logger.warning(`Sell chance was not a number: ${sellChancePercent}, defaulting to ${this.ragfairConfig.sell.chance.base} %`);
             sellChancePercent = this.ragfairConfig.sell.chance.base;
diff --git a/project/src/services/ProfileFixerService.ts b/project/src/services/ProfileFixerService.ts
index de0a45d7..24cf3994 100644
--- a/project/src/services/ProfileFixerService.ts
+++ b/project/src/services/ProfileFixerService.ts
@@ -970,7 +970,7 @@ export class ProfileFixerService
     public fixIncorrectAidValue(fullProfile: IAkiProfile): void
     {
         // Not a number, regenerate
-        if (isNaN(fullProfile.characters.pmc.aid))
+        if (Number.isNaN(fullProfile.characters.pmc.aid))
         {
             fullProfile.characters.pmc.sessionId = <string><unknown>fullProfile.characters.pmc.aid;
             fullProfile.characters.pmc.aid = this.hashUtil.generateAccountId();