diff --git a/lib/internal/encoding.js b/lib/internal/encoding.js
index 5226bf518dac38..78ec2ca1043cf6 100644
--- a/lib/internal/encoding.js
+++ b/lib/internal/encoding.js
@@ -4,10 +4,11 @@
 // https://encoding.spec.whatwg.org
 
 const {
-  Map,
   ObjectCreate,
   ObjectDefineProperties,
   ObjectGetOwnPropertyDescriptors,
+  SafeMap,
+  StringPrototypeSlice,
   Symbol,
   SymbolToStringTag,
   Uint32Array,
@@ -73,7 +74,7 @@ const CONVERTER_FLAGS_IGNORE_BOM = 0x4;
 
 const empty = new Uint8Array(0);
 
-const encodings = new Map([
+const encodings = new SafeMap([
   ['unicode-1-1-utf-8', 'utf-8'],
   ['utf8', 'utf-8'],
   ['utf-8', 'utf-8'],
@@ -308,7 +309,7 @@ function trimAsciiWhitespace(label) {
     label[e - 1] === '\u0020')) {
     e--;
   }
-  return label.slice(s, e);
+  return StringPrototypeSlice(label, s, e);
 }
 
 function getEncodingFromLabel(label) {
@@ -503,7 +504,7 @@ function makeTextDecoderJS() {
         // If the very first result in the stream is a BOM, and we are not
         // explicitly told to ignore it, then we discard it.
         if (result[0] === '\ufeff') {
-          result = result.slice(1);
+          result = StringPrototypeSlice(result, 1);
         }
         this[kBOMSeen] = true;
       }